2001
Anderson,
JF; Vossbrinck, CR; Andreadis, TG; Iton, A; Beckwith, WH 3rd; Mayo, DR. A
phylogenetic approach to following West Nile virus in Connecticut. Proceedings of the
National Academy of Sciences of the United States of America. 2001 Nov
6; 98(23): 12885-9. ISSN: 0027-8424.
NAL
Call No.: 500 N21P
Descriptors:
genetic strains, geographic clusters of mutants,
strain dissemination, phylogeny, virus classification, DNA primers, Cercopithecus-aethiops,
skunk, birds, mosquitoes, Connecticut WN virus isolates.
Molecular
sequence data: GENBANK/AF206517; GENBANK/AF206518; GENBANK/AF206519; GENBANK/AF206520;
GENBANK/AF385215; GENBANK/AF385216; GENBANK/AF385217; GENBANK/AF385218; GENBANK/AF385219;
GENBANK/AF385220; GENBANK/AF385221; GENBANK/AF385222; GENBANK/AF385223; GENBANK/AF385224;
GENBANK/AF385225; GENBANK/AF385226; GENBANK/AF385227; GENBANK/AF385228; GENBANK/AF385229;
GENBANK/AF385230; GENBANK/AF385231; GENBANK/AF385232; GENBANK/AF385233; GENBANK/AF385234;
GENBANK/AF385235; GENBANK/AF385236; GENBANK/AF385237; GENBANK/AF385238; GENBANK/AF385239;
GENBANK/AF385240; GENBANK/AF385241; GENBANK/AF385242; GENBANK/AF385243; GENBANK/AF385244;
GENBANK/AF385245; GENBANK/AF385246; GENBANK/AF385247; GENBANK/AF385248; GENBANK/AF385249;
GENBANK/AF385250; GENBANK/AF385251; GENBANK/AF385252; GENBANK/AF385253; GENBANK/AF385254;
GENBANK/AF385255; GENBANK/AF385256; GENBANK/AF385257; GENBANK/AF385258; GENBANK/AF385259;
GENBANK/AF385260; GENBANK/AF385261; GENBANK/AF385262; GENBANK/AF385263; GENBANK/AF385264;
GENBANK/AF385265; GENBANK/AF385266; GENBANK/AF385267; GENBANK/AF385268; GENBANK/AF385269;
GENBANK/AF385270; GENBANK/AF385271; GENBANK/AF385272; GENBANK/AF385273; GENBANK/AF385274;
GENBANK/AF385275; GENBANK/AF385276; GENBANK/AF385277; GENBANK/AF385278; GENBANK/AF385279;
GENBANK/AF385280; GENBANK/AF385281; GENBANK/AF385282; GENBANK/AF385283; GENBANK/AF385284;
GENBANK/AF385285; GENBANK/AF385286; GENBANK/AF385287; GENBANK/AF385288; GENBANK/AF385289;
GENBANK/AF385290; GENBANK/AF385291; GENBANK/AF385292
Abstract:
The 1999 outbreak of West Nile (WN) virus in the northeastern United States was the first known natural
occurrence of this flavivirus in the Western Hemisphere. In 1999 and 2000, 82
independent Connecticut WN virus isolates were cultured from nine species
of birds, five species of mosquitoes, and one striped skunk. Nucleotide sequences
obtained from these isolates identified 30 genetic changes, compared with
WN-NY99, in a 921-nt region of the viral genome beginning at nucleotide position
205 and ending at 1125. This region encodes portions of the nucleocapsid and
envelope proteins and includes the entire coding regions for the premembrane
and membrane proteins. Amino acid changes occurred at seven loci in six isolates
relative to the WN-NY99 strain. Although 34 of the isolates showed sequences
identical to the WN-NY99 isolate, we were able to show geographical-based
clusters of mutations. In particular, 26 isolates were characterized by mutation
of C to T at position 858. This group apparently originated in Stamford, CT and disseminated to sites
located as far as 54 miles from Stamford. Sequences of WN virus
isolated from both brain and heart tissues from the same avian host were identical
in all 14 tested individual birds, suggesting that the mutations we have documented
are real and not caused by culture, RNA extraction, or PCR procedures. We
conclude that this portion of the viral genome will enable us to follow the
geographical and temporal movement of variant WN virus strains as they adapt
to North
America.
Anderson,
J F; Vossbrinck, C R; Andreadis, T G; Iton, A; Beckwith, W H 3rd; Mayo, D
R. Characterization
of West Nile virus from five species
of mosquitoes, nine species of birds, and one mammal. Annals of the New York Academy of Sciences.
2001
Dec; 951: 328-31. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
virus genetics, isolation and purification, Culicidae, mosquitoes, phylogeny,
skunks, birds.
Andreadis,
T G; Anderson, J F; Vossbrinck, C R. Mosquito
surveillance for West Nile virus in Connecticut, 2000: isolation from
Culex pipiens, Cx. restuans, Cx. salinarius, and Culiseta melanura.
Emerging Infectious Diseases.
2001
Jul-Aug; 7(4): 670-4. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
surveillance data from June to October, mosquito
infection rates with WN, seasonal differences in mosquito transmission, virus
amplication patterns, Culex species
as disease vectors, sentinel surveillance, Cercopithecus aethiops, epidemiology,
Vero cells, virus genetics, Connecticut.
Abstract:
Fourteen isolations of West Nile (WN) virus were obtained from four mosquito
species (Culex pipiens [5], Cx. restuans [4], Cx. salinarius [2], and Culiseta
melanura [3]) in statewide surveillance conducted from June through October
2000. Most isolates were obtained from mosquitoes collected in densely populated
residential locales in Fairfield and New Haven counties, where the highest
rates of dead crow sightings were reported and where WN virus was detected
in 1999. Minimum field infection rates per 1,000 mosquitoes ranged from 0.5
to 1.8 (county based) and from 1.3 to 76.9 (site specific). Cx. restuans appears
to be important in initiating WN virus transmission among birds in early summer;
Cx. pipiens appears to play a greater role in amplifying virus later in the
season. Cs. melanura could be important in the circulation of WN virus among
birds in sylvan environments; Cx. salinarius is a suspected vector of WN virus
to humans and horses.
Anonymous. Serosurveys
for West Nile virus infection--New York and Connecticut counties, 2000. MMWR
Morbidity and Mortality Weekly Report.
2001 Jan 26; 50(3): 37-9. ISSN:
0149-2195.
NAL
Call No.: RA407.3 M56
Descriptors:
West Nile fever epidemiology, areas of epizootic West Nile virus activity,
CDC data, bird/avian mortality, humans, Connecticut, New York.
Abstract:
In
2000, 21 persons were reported with acute illness attributed to West Nile virus (WNV) infection;
19 were hospitalized with encephalitis or meningitis. Of the 21, 10 resided
in the Staten
Island
borough (Richmond County) of New York City. Other ill persons resided
in nine other counties--Kings (Brooklyn), New York (Manhattan), and Queens
counties in New York; Hudson, Passaic, Monmouth, Morris, and Bergen counties
in New Jersey; and Fairfield County in Connecticut. Because ill persons represent
only a fraction of the persons who are infected, many more persons probably
were infected in 2000. To determine the prevalence of recently acquired WNV
infection and associated risk factors for infection, random household cluster
serosurveys were conducted in Staten Island and portions of Fairfield County, Connecticut, and Suffolk County, New York, during October-November
2000. All three areas had intense WNV epizootics as determined by avian mortality
and mosquito surveillance systems. This report summarizes the preliminary
results of this survey and indicates that in areas with intense epizootic
WNV activity, asymptomatic or mildly symptomatic human infections can occur.
Anonymous.
West Nile virus activity--eastern
United States, 2001. MMWR
Morbidity and Mortality Weekly Report.
2001 Jul 27; 50(29): 617-9. ISSN:
0149-2195.
NAL
Call No.: RA407.3 M56
Descriptors:
ArboNET surveillance system data, epidemiology,
birds, Culex mosquitoes, mammals, viral isolation and purification, Mid-Atlantic
region.
Abstract:
In 2000, ArboNET, an enhanced human and animal surveillance system designed
to monitor the geographic spread of West Nile virus (WNV) in the United States and to identify areas
at increased risk for human infections with WNV, detected WNV activity in
the District of Columbia and 12 states. This system,
first implemented in the District of Columbia and 20 states along the
Atlantic and Gulf coasts, was later
expanded throughout the continental United States. This report summarizes
ArboNET data from January 1 through July 25,
2001,
which documents epizootic WNV activity in the southeast and indicates the
need for widespread implementation of WNV prevention activities.
Anonymous.
West Nile virus infection may be
greater than previously thought. FDA Consumer. 2001
Sep-Oct; 35(5): 8. ISSN: 0362-1332.
NAL
Call No.: HD9000.9 U5A1
Descriptors:
viral pathogenecity, disease prevalence, pathogenecity,
epidemiology, New York.
Anomymous.
Proceedings of the International Conference on West
Nile
virus. April 5-7, 2001. White Plains, New York, USA. Annals of
the New York Academy of Sciences. 2001 Dec; 951: 1-374. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
West Nile fever epidemiology, prevention
and control, transmission, humans and animal species affected.
Arroyo,
J; Miller, C A; Catalan, J; Monath, T P. Yellow
fever vector live-virus vaccines: West
Nile
virus vaccine development. Trends
in Molecular Medicine. 2001
Aug; 7(8): 350-4. ISSN: 1471-4914.
Descriptors: gene sequence
modification on viral function, attenuated live virus as a vaccine candidate,
recombinant technology, proteins, therapeutic use, adverse effects, immunology.
Abstract: By
combining molecular-biological techniques with our increased understanding
of the effect of gene sequence modification on viral function, yellow fever
17D, a positive-strand RNA virus vaccine, has been manipulated to induce a
protective immune response against viruses of the same family (e.g. Japanese
encephalitis and dengue viruses). Triggered by the emergence of West Nile virus infections in the
New
World
afflicting humans, horses and birds, the success of this recombinant technology
has prompted the rapid development of a live-virus attenuated candidate vaccine
against West
Nile
virus.
Asnis,
D S; Conetta, R; Waldman, G; Teixeira, A A. The
West Nile virus encephalitis outbreak
in the United States (1999-2000): from Flushing, New York, to beyond its borders.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 161-71.
ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
disease history in Western Hemisphere; flavivirus; endemic in
Africa and Middle East, and S.W. Asia; New York
City outbreak, epidemiology.
Abstract:
Viruses cause most forms of encephalitis. The two main types responsible
for epidemic encephalitis are enteroviruses and arboviruses. The City of New York reports about 10 cases
of encephalitis yearly. Establishing a diagnosis is often difficult. In August
1999, a cluster of five patients with fever, confusion, and weakness were
admitted to a community hospital in Flushing, New York. Flaccid paralysis developed
in four of the five patients, and they required ventilatory support. Three,
less severe, cases presented later in the same month. An investigation was
conducted by the NewYork City (NYC) and New York State (NYS) health departments
and the national Centers for Disease Control and Prevention (CDC). The West
Nile
virus (WNV) was identified as the etiologic agent. WNV is an arthropod-borne
flavivirus, with a geographic distribution in Africa, the Middle East, and southwestern Asia. It has also been isolated
in Australia and sporadically in Europe but never in the Americas. The majority of people
infected have no symptoms. Fever, severe myalgias, headache, conjunctivitis,
lymphadenopathy, and a roseolar rash can occur. Rarely, encephalitis or meningitis
is seen. The NYC outbreak resulted in the first cases of WNV infection in
the Western Hemisphere and the first arboviral
infection in NYC since yellow fever in the nineteenth century. The WNV is
now a public health concern in the United States.
Beasley, D W; Li, L; Suderman,
M T; Barrett, A D. West Nile virus strains differ in
mouse neurovirulence and binding to mouse or human brain membrane receptor
preparations. Annals
of the New York Academy of Sciences. 2001
Dec; 951: 332-5. ISSN: 0077-8923.
NAL Call No.: 500 N484
Descriptors:
viral proteins, genetics, mouse brain tissue
sampling, neuropathology, virulence, receptor binding, mouse model, humans,
molecular sequence data.
Beck,
BR. Hermann Feldmeier: West-Nile-virus ante portas. [Comment
on Hermann Feldmeier: West Nile virus ante portas] Schweizerische
Rundschau fur Medizin Praxis Revue Suisse de Medecine. 2001 Jan 25; 90(4):
127. ISSN: 1013-2058. Letter in German.
Descriptors:
viral horse diseases, virus isolation and purification.
Bernard,
K.A.; Kramer, L.D. West Nile virus activity in the
United States, 2001. Viral Iimmunology.
2001;
14(4): 319-38. ISSN: 0882-8245.
Descriptors:
review article, viral ecology, pathobiology and physiology, transmission patterns,
vectors, reservoirs, epidemic comparisons, other arboviruses, vector transmission
cycles.
Abstract:
West Nile virus (WNV) first appeared
in the naive environment of the Western Hemisphere in 1999 in New York. Genetic analysis determined
that the virus was introduced into the United States from the Mediterranean Basin. This review discusses
the spread of the virus in 2001 from the initial focus in Queens, New York, to widespread activity
in the eastern and midwestern United States. It concentrates on viral
ecology, epizootiology, pathology, prediction, and prevention. Research questions
to further our understanding of the transmission cycle of WNV are discussed,
including host-preference studies, molecular confirmation of implicated mosquito
vectors, and survival of WNV in the temperate environment of the United States. Comparisons are drawn
with two other arboviruses enzootic in the United States, eastern equine encephalitis,
and St. Louis encephalitis viruses. Although not recently introduced, these
two viruses also demonstrated increased activity in the United States in 2001.
Bernard, K A; Maffei,
J G; Jones, S A; Kauffman, E B; Ebel, G; Dupuis, A P 2nd; Ngo, K A; Nicholas,
D C; Young, D M; Shi, P Y; Kulasekera, V L; Eidson, M; White, D J; Stone,
W B; Kramer, L D. West Nile virus infection in birds
and mosquitoes, New York State, 2000.
Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 679-85. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Abstract:
West
Nile
(WN) virus was found throughout New York State in 2000, with the epicenter
in New York City and surrounding counties.
We tested 3,403 dead birds and 9,954 mosquito pools for WN virus during the
transmission season. Sixty-three avian species, representing 30 families and
14 orders, tested positive for WN virus. The highest proportion of dead birds
that tested positive for WN virus was in American Crows in the epicenter (67%
positive, n=907). Eight mosquito species, representing four genera, were positive
for WN virus. The minimum infection rate per 1,000 mosquitoes (MIR) was highest
for Culex pipiens in the epicenter: 3.53 for the entire season and 7.49 for
the peak week of August 13. Staten Island had the highest MIR (11.42
for Cx. pipiens), which was associated with the highest proportion of dead
American Crows that tested positive for WN virus (92%, n=48) and the highest
number of human cases (n=10).
Descriptors:
mortality in bird species, susceptibility of
birds, mosquito pools, Culex pipiens, Aedes, Anopheles, New York epidemiology,
American crows mortality, transmission and spread of disease to humans and
animals
Borowski,
P; Niebuhr, A; Mueller, O; Bretner, M; Felczak, K; Kulikowski, T; Schmitz,
H. Purification and characterization of West Nile virus nucleoside triphosphatase
(NTPase)/helicase: evidence for dissociation of the NTPase and helicase activities
of the enzyme. Journal
of Virology. 2001
Apr; 75(7): 3220-9. ISSN: 0022-538X.
NAL
Call No.: QR360.J6
Descriptors:
viral genetics, enzyme molecular structure,
ATPase, acid anhydride, hydrolases, viral isolation and purification, Vero
cells, RNA helicases, adenosine triphosphate pharmacology, Cercopithecus-aethiops,
guanine, Vero cells
Abstract:
The nucleoside triphosphatase (NTPase)/helicase associated with nonstructural
protein 3 of West Nile (WN) virus was purified from cell culture medium harvested
from virus-infected Vero cells. The purification procedure included sequential
chromatography on Superdex-200 and Reactive Red 120 columns, followed by a
concentration step on an Ultrogel hydroxyapatite column. The nature of the
purified protein was confirmed by immunoblot analysis using a WN virus-positive
antiserum, determination of its NH(2) terminus by microsequencing, and a binding
assay with 5'-[(14)C]fluorosulfonylbenzoyladenosine. Under optimized reaction
conditions the enzyme catalyzed the hydrolysis of ATP and the unwinding of
the DNA duplex with k(cat) values of 133 and 5.5 x 10(-3) s(-1), respectively.
Characterization of the NTPase activity of the WN virus enzyme revealed that
optimum conditions with respect to the Mg(2+) requirement and the monovalent
salt or polynucleotide response differed from those of other flavivirus NTPases.
Initial kinetic studies demonstrated that the inhibition (or activation) of
ATPase activity by ribavirin-5'-triphosphate is not directly related to changes
in the helicase activity of the enzyme. Further analysis using guanine and
O(6)-benzoylguanine derivatives revealed that the ATPase activity of WN virus
NTPase/helicase may be modulated, i.e., increased or reduced, with no effect
on the helicase activity of the enzyme. On the other hand the helicase activity
could be modulated without changing the ATPase activity. Our observations
show that the number of ATP hydrolysis events per unwinding cycle is not a
constant value.
Brinton, MA. Host
factors involved in West Nile virus replication. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 207-19. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
post viral replication factors, cell proteins
in host, viral RNA promoters, protein isolation and purification, birds, Culicidae,
mammals, birds, mice, disease susceptibility, carrier proteins, RNA binding-Proteins,
West Nile virus genetics.
Abstract:
Viruses use cell proteins during many stages of their replication cycles,
including attachment, entry, translation, transcription/replication, and assembly.
Mutations in the cell proteins involved can cause disruptions of these critical
host-virus interactions, which in turn can affect the efficiency of virus
replication. These host-virus interactions also represent novel targets for
the development of new antiviral agents. The different alleles of the murine
Flv gene confer resistance or susceptibility to flavivirus-induced disease
and provide a natural mutant system for the study of a host protein that can
alter the outcome of a flavivirus infection. Since flaviviruses, such as West Nile virus, replicate in mosquitoes,
mammals, and birds during their natural transmission cycles, it is expected
that the critical cell proteins used by these viruses will be ones that are
highly conserved between divergent host species. Our laboratory has focused
on the identification and characterization of the flavivirus resistance gene
product and of cell proteins that interact with the 3' terminal regions of
the West
Nile
virus genomic and antigenomic RNAs. The 3' terminal regions of the viral RNAs
function as promotors for viral RNA replication. Cell proteins that bind to
the viral 3' RNAs were detected by gel shift and UV-induced cross-linking
assays. Individual proteins were then purified and partially sequenced. Mutation
of a mapped, protein-binding site within the 3' terminal region of the viral
RNA in an infectious West
Nile
virus clone was used to demonstrate the functional importance of one of the
cell proteins for efficient West Nile virus replication. Data
from additional studies suggested possible roles for this viral RNA-cell protein
interaction during the flavivirus replication cycle.
Bunning,
M L; Bowen, R A; Cropp, B; Sullivan, K; Davis, B; Komar, N; Godsey, M; Baker,
D; Hettler, D; Holmes, D; Mitchell, C J.
Experimental infection of horses with West Nile virus and their potential
to infect mosquitoes and serve as amplifying hosts. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 338-9.
ISSN: 0077-8923.
NAL Call No.: 500 N484
Descriptors:
Aedes mosquito as disease, vectors, transmission of horse diseases, virology,
pathogenicity, amplifying of viral disease, immunologic response.
Byrne, S N; Halliday, G M; Johnston, L J; King, N J. Interleukin-1beta
but not tumor necrosis factor is involved in West Nile virus-induced Langerhans
cell migration from the skin in C57BL/6 mice. Journal
of Investigative Dermatology. 2001
Sep; 117(3): 702-9. ISSN: 0022-202X.
NAL Call No.: 448.8 J8292
Descriptors:
interleukin-1 immunology, Langerhans cells, skin, tumor necrosis factor, cell
movement, experimental infection in a mouse model, draining lymph, flow cytometry.
Abstract:
Langerhans cells are bone marrow-derived epidermal dendritic cells. They
migrate out of the epidermis into the lymphatics and travel to the draining
lymph nodes where they are responsible for the activation of T cells in the
primary immune response. Tumor necrosis factor and interleukin-1beta, have
previously been shown to be responsible for Langerhans cell migration in response
to contact sensitizers in BALB/C mice; however, which cytokines are responsible
for mediating Langerhans cell migration in response to a replicating cutaneously
acquired virus such as the West Nile virus, are not known. We have devised
a method for identifying Langerhans cells in the draining lymph nodes using
E-cadherin labeling and flow cytometry. We infected tumor necrosis factor-deficient
gene knockout mice (tumor necrosis factor-/-) intradermally with West Nile
virus and found that levels of Langerhans cell emigration and accumulation
in the draining lymph nodes were similar to wild-type C57BL/6 mice. This was
borne out by the finding that high levels of systemic neutralizing anti-tumor
necrosis factor antibody failed to inhibit the migration of Langerhans cells
from the epidermis and their accumulation in the draining lymph nodes in wild-type
C57BL/6 mice. In West Nile virus-infected, tumor necrosis factor-/- mice treated
with systemic neutralizing anti-interleukin-1beta antibodies, however, migration
of Langerhans cells from the epidermis and their accumulation in the draining
lymph nodes were significantly inhibited compared with control antibody-treated,
infected animals. The results indicate that Langerhans cell migration, accumulation
in the draining lymph nodes and the initiation of lymph node shut-down in
response to a cutaneous West Nile virus infection is dependent on interleukin-1beta
and can occur in the absence of tumor necrosis factor.
Campbell,
G L; Grady, L J; Huang, C; Lanciotti, R; Kramer, L; Roehrig, J T; Shope, R E.
Laboratory
testing for West Nile virus: panel discussion.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 179-94.
ISSN: 0077-8923.
NAL Call No.: 500 N484
Descriptors:
West Nile virus, diagnosis, immunology, blood antigens, ELISA, reverse transcriptase PCR,
epidemiology, viral genetics, viral isolation and purification.
Cannon,
C E; Pavlin, J A; Vaeth, M F; Ludwig, G V; Writer, J V; Pagac, B B; Goldenbaum,
M B; Kelley, P W. Department of Defense West Nile virus surveillance.
Annals of the New York Academy of Sciences.
2001 Dec; 951: 340-2. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
U.S. Department of Defense, surveillance program,
epidemiology, ELISA assay, mammals, humans, Culicidae, vector virology, U.S.
Cantile, C.; F. Del Piero; G. Di Guardo; M. Arispici. Pathologic and immunohistochemical
findings in naturally occurring West Nile virus infection in horses. Veterinary
Pathology. July 2001. v. 38 (4) p. 414-421. ISSN: 0300-9858.
NAL call no: 41.8 P27
Descriptors: horses, West Nile virus, West Nile fever, pathology, lesions,
immunohistochemistry, animal tissues, viral antigens, phenotypes, central nervous
system, organs, USA, Italy.
Carlson,
RH. West Nile virus in the USA--an update. Lancet
Infectious Diseases. 2001 Oct; 1(3): 143. ISSN:
1473-3099.
Descriptors:
epidemiology, disease vectors, disease reservoirs,
transmission factors, bird migration, disease spread, U.S.
Ceianu, C S; Ungureanu,
A; Nicolescu, G; Cernescu, C; Nitescu, L; Tardei, G; Petrescu, A; Pitigoi, D;
Martin, D; Ciulacu Purcarea, V; Vladimirescu, A; Savage, H M. West nile virus surveillance in
Romania: 1997-2000. Viral Immunology.
2001;
14(3): 251-62. ISSN:
0882-8245.
Descriptors:
West Nile virus immunology, sentinel surveillance, wild bird diseases, humans,
Culex mosquito virology, domestic fowl, seasonal persistence.
Abstract:
In response to the 1996 West Nile (WN) fever epidemic that occurred in
Bucharest and southeastern Romania, a surveillance program
was established. The surveillance system detected 39 clinical human WN fever
cases during the period 1997-2000: 14 cases in 1997, 5 cases in 1998, 7 cases
in 1999, and 13 cases in 2000. Thirty-eight of the 39 case-patients lived in
the greater Danube Valley of southern Romania, and 1 case-patient resided
in the district of Vaslui, located on the Moldavian plateau. The estimated annual
case incidence rate for the surveillance area during the period 1997-2000 was
0.95 cases per million residents. Thirty-four cases were serologically confirmed,
and 5 cases were classified as probable. Twenty-four case-patients presented
with clinical symptoms of meningitis (62%), 12 with meningoencephalitis (31%),
1 with encephalitis (3%), and 2 with febrile exanthema (5%). Five of the 39
cases were fatal (13%). Fourteen case-patients resided in rural areas, and 25
in urban and suburban areas, including 7 case-patients who resided in Bucharest. The ages of case-patients
ranged from 8 to 76 years with a median age of 45 years. Twenty-four
case-patients were males and 15 were females. Dates of onset of illness occurred
from May 24 through September 25, with 82% of onset dates occurring in August
and September. Limited entomological surveillance failed to detect WN virus.
Retrospective sampling of domestic fowl in the vicinity of case-patient residences
during the years 1997-2000 demonstrated seroprevalence rates of 7.8%-29%. Limited
wild bird surveillance demonstrated seroprevalence rates of 5%-8%. The surveillance
data suggest that WN virus persists focally for several years in poorly understood
transmission cycles after sporadic introductions or that WN virus is introduced
into Romania at relatively high rates,
and persists seasonally in small foci.
Cherry, B; Trock, S C; Glaser, A; Kramer, L; Ebel, G D; Glaser, C; Miller, J
R. Sentinel chickens as a surveillance tool for West
Nile
virus in New York City, 2000.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 343-6. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
disease incidence, disease monitoring, chickens
as sentinel animals, domestic fowl, disease prevention and control, ELISA, predictive
value of tests, immunology.
Covello, V T;
Peters, R G; Wojtecki, J G; Hyde, R C. Risk communication,
the West Nile virus epidemic, and bioterrorism:
responding to the communication challenges posed by the intentional or unintentional
release of a pathogen in an urban setting. Journal
of Urban Health Bulletin of the New York Academy of Medicine.
2001 Jun; 78(2): 382-91. ISSN: 1099-3460.
Descriptors:
disease risk assessment communication, theoretical perspective, risk communication
models, communication management, bioterrorism psychology, New York City.
Abstract:
The
intentional or unintentional introduction of a pathogen in an urban setting
presents severe communication challenges. Risk communication--a science-based
approach for communicating effectively in high-concern situations--provides
a set of principles and tools for meeting those challenges. A brief overview
of the risk communication theoretical perspective and basic risk communication
models is presented here, and the risk communication perspective is applied
to the West Nile virus epidemic in New York City in 1999 and 2000 and to
a possible bioterrorist event. The purpose is to provide practical information
on how perceptions of the risks associated with a disease outbreak might be
perceived and how communications would be best managed.
Craven, R B; Roehrig,
J T. West Nile virus. JAMA --
The Journal of the American Medical Association. 2001
Aug 8; 286(6): 651-3. ISSN:
0098-7484.
NAL
Call No.: 448.9 Am37
Descriptors:
disease diagnosis, epidemiology, disease prevention
and control, birds, insect vectors, Culicidae, viral isolation and purification,
therapy.
Davis, B S; Chang, G
J; Cropp, B; Roehrig, J T; Martin, D A; Mitchell, C J; Bowen, R; Bunning, M
L. West Nile virus recombinant DNA
vaccine protects mouse and horse from virus challenge and expresses in vitro
a noninfectious recombinant antigen that can be used in enzyme-linked immunosorbent
assays. Journal of Virology.
2001 May; 75(9): 4040-7.
ISSN: 0022-538X.
NAL
Call No.: QR360.J6
Descriptors:
intramuscular administration of vaccines, recombinant plasmid expressing WN
virus prM and E proteins, efficacy in mice and horses, anitigen form cell culture,
disease prevention and control.
Abstract:
Introduction of West Nile (WN) virus into the United States in 1999 created major
human and animal health concerns. Currently, no human or veterinary vaccine
is available to prevent WN viral infection, and mosquito control is the only
practical strategy to combat the spread of disease. Starting with a previously
designed eukaryotic expression vector, we constructed a recombinant plasmid
(pCBWN) that expressed the WN virus prM and E proteins. A single intramuscular
injection of pCBWN DNA induced protective immunity, preventing WN virus infection
in mice and horses. Recombinant plasmid-transformed COS-1 cells expressed and
secreted high levels of WN virus prM and E proteins into the culture medium.
The medium was treated with polyethylene glycol to concentrate proteins. The
resultant, containing high-titered recombinant WN virus antigen, proved to be
an excellent alternative to the more traditional suckling-mouse brain WN virus
antigen used in the immunoglobulin M (IgM) antibody-capture and indirect IgG
enzyme-linked immunosorbent assays. This recombinant antigen has great potential
to become the antigen of choice and will facilitate the standardization of reagents
and implementation of WN virus surveillance in the United States and elsewhere.
Deubel,
V; Gubler, D J; Layton, M; Malkinson, M. West Nile virus: a newly emergent
epidemic disease. Emerging Infectious
Diseases. 2001; 7(3 Suppl): 536. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
emerging disease epidemiology, Culex mosquitoes
virology, disease prevention and control, birds as disease reservoirs, epidemiology,
role of migratory birds.
Dohm, D.J.; M. Turell. Effect of incubation at overwintering temperatures
on the replication of West Nile virus in New York Culex pipiens (Diptera: Culicidae).
Journal of Medical Entomology. May 2001. v. 38 (3) p. 462-464. ISSN:
0022-2585.
NAL call no: 421 J828
Descriptors: Culex pipiens, West Nile virus, disease vectors, experimental
infections, mosquitoes, viral replication, disseminated infections,
overwintering, environmental temperature, simulation, New York.
Abstract: We examined the effect of simulated overwintering
temperatures on West Nile (WN) virus replication in Culex pipiens L. derived
from mosquitoes collected during the autumn 1999 WN epizootic in New York. The
WN virus was a strain isolated from a dead crow also collected during this
outbreak. Virus was recovered from most mosquitoes held exclusively at 26
degrees C. In contrast, none of the mosquitoes held exclusively at the lower
temperatures had detectable infections. When mosquitoes were transferred to 26
degrees C after being held at 10 degrees C for 21-42 d, infection and
dissemination rates increased with increased incubation at 26 degrees C. Future
studies involving the attempted isolation of WN virus from overwintering
mosquitoes may benefit from holding the mosquitoes at 26 degrees C before
testing for infectious virus.
Ebel, G D; Dupuis, A P 2nd; Ngo, K; Nicholas, D; Kauffman, E; Jones, S A; Young,
D; Maffei, J; Shi, P Y; Bernard, K; Kramer, L D. Partial
genetic characterization of West Nile virus strains, New York State, 2000.
Emerging Infectious Diseases. 2001
Jul-Aug; 7(4): 650-3. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
viral strains analysis, envelope genes, nucleotide sequences, reverse transcriptase
PCR, viral amplification methodologies, genetic differences.
Abstract:
We analyzed nucleotide sequences from the envelope gene of 11 West Nile
(WN) virus strains collected in New York State during the 2000 transmission
season to determine whether they differed genetically from each other and from
the initial strain isolated in 1999. The complete envelope genes of these strains
were amplified by reverse transcription-polymerase chain reaction. The resulting
sequences were aligned, the genetic distances were computed, and a phylogenetic
tree was constructed. Ten (0.7%) of 1,503 positions in the envelope gene were
polymorphic in one or more sequences. The genetic distances were 0.003 or less.
WN virus strains circulating in 2000 were homogeneous with respect to one another
and to a strain isolated in 1999.
Eidson,
M "Neon
needles" in a haystack: the advantages of passive surveillance for West
Nile virus. Annals of the New York Academy of Sciences.
2001 Dec; 951: 38-53. ISSN: 0077-8923.
NAL Call No.: 500 N484
Descriptors:
disease reservoirs, epidemiology, population
surveillance, crow mortality rates, virus levels, correlation of dead crows
to human disease.
Abstract:
Passive surveillance is usually viewed as less efficient for case ascertainment
than active surveillance. However, for diseases with nonhuman animal reservoirs,
active surveillance can be like looking for a needle in a haystack and may be
prohibitively expensive. Fortunately for surveillance of West Nile virus (WNV)
in the northeast US, the dead crows have served as "neon needles in a haystack"--indicators
of viral activity that call attention to themselves. In 2000, laboratory testing
of dead birds, including all species, birds found singly, with signs of trauma,
or no compatible pathology, provided the first confirmation of viral activity
in most areas. The surveillance factor most closely associated with the number
of human cases was the dead crow density. In 2001, dead crow densities will
be used as an additional index for monitoring human risk and need for prevention
and control activities. If there are few crows in an area, if their case-fatality
rate is reduced, or if there is public complacency about reporting dead crow
sightings, this passive surveillance indicator may not be helpful in identifying
areas likely to have occasional human cases or an outbreak.
Eidson, M; Komar,
N; Sorhage, F; Nelson, R; Talbot, T; Mostashari, F; McLean, R. Crow
deaths as a sentinel surveillance system for West Nile virus in the northeastern
United States, 1999. Emerging Infectious Diseases. 2001
Jul-Aug; 7(4): 615-20. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
virus prevalence, surveillance, songbirds, dead
crows as indicators of viral activity, relationship of bird mortality to human
cases, disease reservoir, geographic distribution, New Jersey, New York, Connecticut.
Abstract:
In addition to human encephalitis and meningitis cases, the West Nile (WN)
virus outbreak in the summer and fall of 1999 in New York State resulted in bird deaths
in New
York,
New
Jersey, and Connecticut. From August to December
1999, 295 dead birds were laboratory-confirmed with WN virus infection; 262
(89%) were American Crows (Corvus brachyrhynchos). The New York State Department
of Health received reports of 17,339 dead birds, including 5,697 (33%) crows;
in Connecticut 1,040 dead crows were reported. Bird deaths were critical in
identifying WN virus as the cause of the human outbreak and defining its geographic
and temporal limits. If established before a WN virus outbreak, a surveillance
system based on bird deaths may provide a sensitive method of detecting WN virus.
Eidson, M; Kramer, L; Stone, W; Hagiwara, Y; Schmit, K. Dead
bird surveillance as an early warning system for West Nile virus.
Emerging Infectious Diseases. 2001 Jul-Aug; 7(4):
631-5. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
early detection, virus surveillance system, dead diseased crows, songbirds,
correlation between bird deaths and human disease, mosquito vector control,
predictive value of tests, sentinel surveillance, New York.
Abstract:
As part of West Nile (WN) virus surveillance in New York State in 2000, 71,332 ill or
dead birds were reported; 17,571 (24.6%) of these were American Crows. Of 3,976
dead birds tested, 1,263 (31.8%) were positive for WN virus. Viral activity
was first confirmed in 60 of the state's 62 counties with WN virus-positive
dead birds. Pathologic findings compatible with WN virus were seen in 1,576
birds (39.6% of those tested), of which 832 (52.8%) were positive for WN virus.
Dead crow reports preceded confirmation of viral activity by several months,
and WN virus-positive birds were found >3 months before the onset of human
cases. Dead bird surveillance appears to be valuable for early detection of
WN virus and for guiding public education and mosquito control efforts.
Eidson, M; Miller, J; Kramer, L; Cherry, B; Hagiwara, Y. Dead crow densities
and human cases of West Nile virus, New York State, 2000. Emerging
Infectious Diseases. 2001 Jul Aug; 7(4): 662 4. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
epidemiolgy, monitoring of dead crow densities, viral levels, correlation with
human cases, specimen collection and testing, disease reservoirs, New York City.
Abstract:
In 2000, Staten Island, New York, reported 10 human West Nile virus cases and high densities
of dead crows. Surrounding counties with <2 human cases had moderate dead
crow densities, and upstate counties with no human cases had low dead crow densities.
Monitoring such densities may be helpful because this factor may be determined
without the delays associated with specimen collection and testing.
Epstein, P R. West Nile virus and the climate. Journal
of Urban Health Bulletin of the New York Academy of Medicine. 2001
Jun; 78(2): 367-71. ISSN: 1099-3460.
Descriptors:
factors affecting survival and disease spread,
urban dwelling birds and mosquitoes, effect of warm winters and spring drought,
vector control measures, breeding places, climatic change, mosquito borne diseases,
ovicides and larvicides, North America.
Abstract:
West Nile virus is transmitted by urban-dwelling mosquitoes to birds and
other animals, with occasional "spillover" to humans. While the means
by which West Nile virus was introduced into the Americas in 1999 remain unknown,
the climatic conditions that amplify diseases that cycle among urban mosquitoes,
birds, and humans are warm winters and spring droughts. This information can
be useful in generating early warning systems and mobilizing timely and the
most environmentally friendly public health interventions. The extreme weather
conditions accompanying long-term climate change may also be contributing to
the spread of West
Nile
virus in the United States and Europe.
Farello, C A; Sorhage, F E; Bresnitz, E A; Grant, C. West Nile virus:
New Jersey's 2000 experience and surveillance plans for 2001. New
Jersey Medicine the Journal of the Medical Society of New Jersey. 2001
Jul; 98(7): 25-32.
ISSN:
0885-842X.
Descriptors:
viral prevelance and dead birds surveillance
program, transmission patterns, disease prevention and control, virus isolation
and purification, New Jersey.
Garmendia, A E;
Van Kruiningen, H J; French, R A. The West Nile virus: its recent
emergence in North America. Microbes
and Infection Institut Pasteur. 2001 Mar; 3(3): 223-9. ISSN: 1286-4579.
NAL
Call No.: QR180 M53
Descriptors:
review article, history of disease emergence
starting in 1999, humans, horses, wild birds, correlation between human disease
and bird mortality, mosquito vectors, Chiroptera virology, bats, Culicidae virology,
surveillance data.
Abstract:
West Nile fever emerged in New York in the summer of 1999
when seven people, several horses and thousands of wild birds died. It was soon
established that the human disease and the mortality of birds were related.
Continued surveillance detected West Nile virus in mosquitoes, birds, horses,
small mammals, bats and humans, and has shown its spread to several northeastern
states. These events confirm the establishment of West Nile virus endemically in the
United States.
Gotham, I J; Eidson,
M; White, D J; Wallace, B J; Chang, H G; Johnson, G S; Napoli, J P; Sottolano,
D L; Birkhead, G S; Morse, D L; Smith, P F. West Nile virus: a case study in how
NY State Health Information infrastructure facilitates preparation and response
to disease outbreaks. Journal
of Public Health Management and Practice. 2001
Sep; 7(5): 75-86. ISSN:
1078-4659
Descriptors:
New York State Health Information Network, integrated
surveillance system, humans, birds, other mammals, mosquitoes, tracking, retrieval
of data on disease outbreaks, disaster planning, communication plans.
Abstract:
New York's (NY) Health Information
Network (HIN) provided timely access to West Nile virus (WNV) data during the
initial outbreak in the late Summer 1999. In December 1999, NY developed a plan
to deal with WNV in 2000 that required an integrated surveillance system for
humans, birds, mammals, and mosquitoes. The HIN infrastructure allowed NY to
deploy this system statewide in three months. Local health departments throughout
NY used the system to report, track, and retrieve surveillance data as WNV spread
throughout NY in 2000. The HIN infrastructure includes partnerships, training/support,
technical capacity and architecture similar to NEDSS as proposed by the US CDC.
Groot, de A S;
Saint Aubin, C; Bosma, A; Sbai, H; Rayner, J; Martin, W. Rapid determination of HLA B*07 ligands
from the West Nile virus NY99 genome. Emerging
Infectious Diseases. 2001 Jul Aug; 7(4): 706 13. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
T lymphocyte epitopes, subunit vaccine development,
genome mapping, rapid and inexpensive methodologies, ligands useful for cell-mediated
response, possible diagnostic reagents.
Abstract:
Defined T cell epitopes for West Nile (WN) virus may be useful for developing
subunit vaccines against WN virus infection and diagnostic reagents to detect
WN virus-specific immune response. We applied a bioinformatics (EpiMatrix) approach
to search the WN virus NY99 genome for HLA B*07 restricted cytotoxic T cell
(CTL) epitopes. Ninety-five of 3,433 WN virus peptides scored above a predetermined
cutoff, suggesting that these would be likely to bind to HLA B*07 and would
also be likely candidate CTL epitopes. Compared with other methods for genome
mapping, derivation of these ligands was rapid and inexpensive. Major histocompatibility
complex ligands identified by this method may be used to screen T cells from
WN virus-exposed persons for cell-mediated response to WN virus or to develop
diagnostic reagents for immunopathogenesis studies and epidemiologic surveillance.
Hadfield, T L;
Turell, M; Dempsey, M P; David, J; Park, E J. Detection of West
Nile virus in mosquitoes by RT-PCR. Molecular
and Cellular Probes. 2001 Jun; 15(3): 147-50. ISSN: 0890-8508.
NAL
Call No.: 0890-8508
Descriptors:
reverse transcriptase PCR assay, TaqMan, viral
assay method, infected mosquitoes, eastern equine encephalitis virus, Ilheus
virus, yellow fever virus, level of accuracy.
Abstract:
A reverse transcriptase-polymerase chain reaction (RT-PCR) assay employing
<<TaqMan>> detection technology was developed to identify West Nile virus in experimentally
infected mosquitoes. The specificity of the assay was evaluated with the following
viruses: eastern equine encephalitis, Ilheus, West Nile and yellow fever viruses.
The limits of detection were determined using West Nile viral RNA extracted
from serial dilutions of virus culture in infected mosquitoes. Limit of detection
was 5 PFU from extracted mosquitoes. We were able to detect the presence of
one infected mosquito in a pool of 50 repeatedly. When the RT-PCR was used with
coded samples of intrathoracically-infected and uninfected mosquitoes, the assay
detected the virus in all infected mosquitoes. Analytic sensitivity and specificity
were 100%. This assay offers an efficient and rapid method of identifying West
Nile virus in infected mosquitoes or cell culture.
Hadler, J; Nelson,
R; McCarthy, T; Andreadis, T; Lis, M J; French, R; Beckwith, W; Mayo, D; Archambault,
G; Cartter, M. West Nile virus surveillance in Connecticut in
2000: an intense epizootic without high risk for severe human disease.
Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 636-42. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
monitoring bird deaths, testing dead crows and
songbirds, horse disease levels, trapping and testing mosquitoes, human seropervalance
survey, animal sentinel surveillance, Culex virology, insect vector monitoring,
Connecticut.
Abstract:
In 1999, Connecticut was one of three states
in which West Nile (WN) virus actively circulated prior to its recognition.
In 2000, prospective surveillance was established, including monitoring bird
deaths, testing dead crows, trapping and testing mosquitoes, testing horses
and hospitalized humans with neurologic illness, and conducting a human seroprevalence
survey. WN virus was first detected in a dead crow found on July 5 in Fairfield
County. Ultimately, 1,095 dead crows, 14 mosquito pools, 7 horses, and one mildly
symptomatic person were documented with WN virus infection. None of 86 hospitalized
persons with neurologic illness (meningitis, encephalitis, Guillain-Barre-like
syndrome) and no person in the seroprevalence survey were infected. Spraying
in response to positive surveillance findings was minimal. An intense epizootic
of WN virus can occur without having an outbreak of severe human disease in
the absence of emergency adult mosquito management.
Hayes, C G. West Nile virus: Uganda, 1937, to New York City, 1999.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 25-37. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
review article, 3 urban epidemics, risk factors,
viral virulence changes, 60 years of observations about West Nile virus, Culex, pathogenicity,
New York, Uganda.
Abstract:
West Nile virus, first isolated
in 1937, is among the earliest arthropod-borne viruses discovered by humans.
Its broad geographical distribution, not uncommon infection of humans, transmission
by mosquitoes, and association with wild birds as enzootic hosts were well documented
by the mid-1960s. However, West Nile virus was not considered to be a significant
human pathogen because most infections appeared to result in asymptomatic or
only mild febrile disease. Several epidemics had been documented prior to 1996,
some involving hundreds to thousands of cases in mostly rural populations, but
only a few cases of severe neurological disease had been reported. The occurrence
between 1996 and 1999 of three major epidemics, in southern Romania, the Volga
delta in southern Russia, and the northeastern United States, involving hundreds
of cases of severe neurological disease and fatal infections was totally unexpected.
These were the first epidemics reported in large urban populations. A significant
factor that appeared in common to all three outbreaks was the apparent involvement
of the common house mosquito, Culex pipiens, as a vector. This species had not
previously been implicated as important in the transmission of West Nile virus.
In addition the epidemic in the northeastern United States was unusual in the
association of West Nile virus infection with fatal disease of birds, suggesting
a change in the virulence of the virus toward this host. Understanding the risk
factors that contributed to these three urban epidemics is important for minimizing
the potential for future occurrences. This review will attempt to compare observations
on the biology of West Nile virus made over about
60 years prior to the recent epidemics to observations made in association with
these urban epidemics.
Hindiyeh,
M; Shulman, L M; Mendelson, E; Weiss, L; Grossman, Z; Bin, H. Isolation
and characterization of West Nile virus from the blood of viremic patients during
the 2000 outbreak in Israel. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 748-50. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
phylogenetic analysis of the West Nile virus,
disease outbreaks in Israel in 2000, 2 isolates related to New York isolate
and Russian isolate, RNA viral analysis;
reverse transcriptase.
Abstract:
We
report the isolation of West Nile (WN) virus from four patient serum samples
submitted for diagnosis during an outbreak of WN fever in Israel in 2000. Sequencing and
phylogenetic analysis revealed two lineages, one closely related to a 1999 New York isolate and the other
to a 1999 Russian isolate.
Hinkle N. Equine cases of West Nile virus from 1 January
through 19 September, 2001. Vector Ecology
Newsletter. 2001, 32: 3.
Descriptors:
survey of West Nile virus in horses, veterinary diseases, disease incidence, Alabama, Connecticut,
Florida, Georgia, Kentucky, Louisiana, Massachusetts, New Jersey, Pennsylvania,
Virginia.
Hodgson, J.C.; A. Spielman; N. Komar; C. Krahforst; G. Wallace; R. Pollack.
Interrupted blood-feeding by Culiseta melanura (Diptera: Culicidae) on European
starlings. Journal of Medical Entomology. Jan 2001. v.38 (1) p. 59-66.
ISSN: 0022-2585.
NAL call no: 421 J828
Descriptors: Culiseta melanura, mosquitoes, hematophagy, feeding frequency,
blood meals, engorgement, volume, Turdus migratorius, Sturnus vulgaris,
reservoir hosts, host preferences, animal behavior, defense, disease vectors,
eastern equine encephalitis virus, robins, starlings, Massachusetts.
Abstract: To determine whether Culiseta melanura (Coquillett) mosquitoes
tend to take multiple blood meals when birds of certain species serve as hosts,
we compared the frequencies with which such mosquitoes fed upon caged starlings
and robins and determined whether similar volumes of blood were imbibed from
each. The blood of robins (Turdus migratorius) and European starlings (Sturnus
vulgaris) was marked contrastingly by injecting birds with rubidium or cesium
salts. Caged birds were placed together in a natural wetland setting overnight.
Mosquitoes captured nearby on the following morning were analyzed for each of
the elemental markers. Where marked robins and starlings were equally abundant,
43% of freshly engorged Cs. melanura fed on more than or equal to two hosts.
More Cs. melanura fed on robins than on starlings. Individual mosquitoes tended
to contain far more robin- than starling-associated marker, indicating that
mosquitoes "feasted" on robins but only "nibbled" on starlings.
Mosquitoes marked with both elements apparently fed meagerly on the starlings
then abundantly on the robins. Our estimates of bloodmeal volume indicate that
85% of mosquitoes that fed on marked starlings obtained <0.5 microliter of
blood from them. We suggest that defensive behavior by starlings interrupts
mosquito blood-feeding and that, in a communal roost of starlings, each mosquito
will tend to feed on more than one bird, thereby promoting rapid transmission
of such ornithonotic arboviruses as eastern equine encephalomyelitis virus and
West Nile virus.
Johnson, D J;
Ostlund, E N; Pedersen, D D; Schmitt, B J. Detection of North American West Nile
virus in animal tissue by a reverse transcription-nested polymerase chain reaction
assay. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 739-41. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
RT nested PCR virus detection method, bird tissue samples, infected cell cultures,
sensitivity to detection of virus in equine tissues.
Abstract:
A
traditional single-stage reverse transcription-polymerase chain reaction (RT-PCR)
procedure is effective in determining West Nile (WN) virus in avian tissue and
infected cell cultures. However, the procedure lacks the sensitivity to detect
WN virus in equine tissue. We describe an RT-nested PCR (RT-nPCR) procedure
that identifies the North American strain of WN virus directly in equine and
avian tissues.
Jupp, PG. The ecology of West Nile virus in South Africa
and the occurrence of outbreaks in humans.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 143-52.ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
review paper, research/studies in South Africa’s
inland plateau, epizootic transmission cycle, mosquitoes, birds as viral reservoirs
and disease spreaders, dogs, Culex species, strain causes mild illness in humans,
Culex univittatus, Culex theileri, vector mosquitoes.
Abstract:
This
paper reviews studies done on West Nile virus (WNV) in South Africa, mainly between 1962 and
1980 on the temperate inland plateau (Highveld and Karoo). The virus is maintained
in an enzootic transmission cycle between feral birds and the ornithophilic
mosquito Culex univittatus. About 30 avian species have been shown to be involved
without mortality. Humans, and other mammals, although they may have antibodies,
are considered blind-alleys in the transmission cycle except perhaps some dogs.
Cx. univittatus also transfers infection to humans, almost invariably causing
only a mild illness. Its usually low anthropophilism may explain why annual
human infection on the Highveld is limited to sporadic cases. Besides multiple
isolations from field collections of Cx. univittatus, this mosquito is both
highly susceptible to the virus and an efficient transmitter. Culex theileri
is a minor vector. In the summer of 1974 there was a large epidemic in the dry
Karoo after unusual rains: there were many human cases, the infection rate in
Cx. univittatus was 39.0/1000, and postepidemic immune rates in humans and birds
were high. In 1984 there was an epizootic in Gauteng Province in the Highveld
with an infection rate in Cx. univittatus reaching 9.6/1000 and more human infections
than usual. The much lower immune rates in the KwaZulu-Natal coastal lowlands
than on the plateau and the single isolation from Cx. neavei, which replaces
Cx. univittatus in the lowlands, are explained by the low susceptibility of
Cx. neavei to the virus. Genetic relatedness of isolates from different countries
showed two lineages, with one lineage comprising only African isolates, including
25 South African strains, which had a sequence homology of 86.3-100%. This suggests
that the viral enzooticity does not depend on annual importation of virus in
migrant birds.
Kallio S; Hanninen ML. West Nile-viruksen aiheuttamat epidemiat:
kirjallisuuskatsaus [Epidemics caused by West Nile virus: a literature review.]
Suomen
Elainlaakarilehti. 2001, 107: 9, 501-504; 11 ref. In Finnish.
NAL
Call No.: 41.8 N813
Descriptors:
history of pathogenic virus migration
out of the Nile area of Africa, Romania, biology of disease, control of vector
mosquitoes, mosquito control via larvae control, transmission factors.
Kauffman, E B; Bernard, K A; Jones, S A; Maffei, J; Ngo, K; Kramer, L D. West
Nile virus laboratory surveillance program: cost and time analysis. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 351-3. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
virology study, economics, epidemiology, isolation and purification, disease
prevention and control, viral genetics, disease population surveillance, costs
and cost analysis, Culicidae mosquito vectors, reverse transcriptase polymerase
chain reaction, viral genetics, New York
State program.
Klimes, J.; Z. Juricova; I. Literak; P. Schanilec; E. Silva. Prevalence
of antibodies to tickborne encephalitis and West Nile flaviviruses and the clinical
signs of tickborne encephalitis in dogs in the Czech Republic. Veterinary
Record. Jan 6, 2001. v. 148 (1) p. 17-20. ISSN: 0042-4900.
NAL call no: 41.8 V641
Descriptors: dogs, tickborne encephalitis virus, seroprevalence, antibodies,
tickborne encephalitis, West Nile virus, clinical aspects, cross reaction, rottweiler,
Czech Republic.
Komar, N. West Nile virus surveillance using sentinel birds.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 58-73. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
monitoring of virus levels, sentinel house sparrows
and pigeons, selection of monitoring
sites, Culex pipiens disease vectors.
Abstract:
Captive
and free-ranging birds have been used for decades as living sentinels in arbovirus
surveillance programs. This review summarizes information relevant to selecting
sentinel bird species for use in surveillance of West Nile (WN) virus. Although
experience using avian sentinels for WN virus surveillance is limited, sentinels
should be useful for both detecting and monitoring WN virus transmission; however,
sentinel bird surveillance systems have yet to be adequately tested for use
with the North American strain of WN virus. Captive chickens are typically used
for arbovirus surveillance, but other captive species may be used as well. Serosurvey
and experimental infection data suggest that both chickens and pigeons show
promise as useful captive sentinels; both species were naturally exposed during
the epizootics in New York City, 1999-2000, and both species develop antibodies
after infection without becoming highly infectious to Culex pipiens vectors.
Wild bird species that should be targeted for use as free-ranging sentinels
include house sparrows and pigeons. The ideal wild bird should be determined
locally on the basis of seroprevalence studies. Interpreting serological data
generated from studies using free-ranging sentinel birds is complex, however.
Sentinel bird monitoring sites should be selected in enzootic transmission foci.
Several years of observation may be required for selection of effective sentinel
monitoring sites.
Komar, N; Panella, N A; Boyce, E. Exposure of domestic mammals
to West Nile virus during an outbreak of human encephalitis, New York City,
1999. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 736-8. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
monitoring of disease in horses, dogs and cats,
possible role as sentinels, immunology, neutralization tests, seroepidemiology
studies, New York City.
Abstract:
We
evaluated West Nile (WN) virus seroprevalence in healthy horses, dogs, and cats
in New York City after an outbreak of human
WN virus encephalitis in 1999. Two (3%) of 73 horses, 10 (5%) of 189 dogs, and
none of 12 cats tested positive for WN virus-neutralizing antibodies. Domestic
mammals should be evaluated as sentinels for local WN virus activity and predictors
of the infection in humans.
Komar, N; Panella, N A; Burns, J E; Dusza, S W; Mascarenhas, T M; Talbot, T
O. Serologic evidence for West Nile virus infection in birds
in the New York City vicinity during an outbreak in 1999. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 621-5. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
seropositive songbirds, domestic geese, chickens,
house sparrows, Canada geese, rock doves, sentinel animals, viral reservoirs,
bood sampling.
Abstract:
As
part of an investigation of an encephalitis outbreak in New York City, we sampled 430 birds,
representing 18 species in four orders, during September
13-23, 1999,
in Queens and surrounding counties.
Overall, 33% were positive for West Nile (WN) virus-neutralizing antibodies,
and 0.5% were positive for St. Louis encephalitis virus-neutralizing antibodies.
By county, Queens had the most seropositive birds for WN virus (50%); species
with the greatest seropositivity for WN virus (sample sizes were at least six)
were Domestic Goose, Domestic Chicken, House Sparrow, Canada Goose, and Rock
Dove. One sampled bird, a captive adult Domestic Goose, showed signs of illness;
WN virus infection was confirmed. Our results support the concept that chickens
and House Sparrows are good arbovirus sentinels. This study also implicates
the House Sparrow as an important vertebrate reservoir host.
Kramer, L D; Bernard, K A
West Nile virus in the western hemisphere.
Current
Opinion in Infectious Diseases. 2001 Oct; 14(5): 519-25.
ISSN: 0951-7375
Descriptors:
review article, disease introduction into New York City, disease establishment,
transmission biology and cycle, disease vector mosquitoes, prevention and control
of spread, invasive species.
Abstract:
West Nile virus first appeared in
the western hemisphere in 1999 in New York. Genetic analysis determined
that the virus was introduced from the Mediterranean Basin. This review discusses
the establishment of West Nile virus in the naive environment
of the northeastern USA, its ecology, epizootiology,
pathology, prevention and prediction, as well as laboratory studies that have
been conducted to elucidate the transmission cycle.
Kramer, L D; Bernard,
K A. West Nile virus infection in birds and
mammals. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 84-93. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
dead bird sampling, percentage carrying West
Nile virus, highest mortality in crows, kidney viremia levels, experimental
infection in mice.
Abstract:
West
Nile virus (WNV) was found throughout New York State in year 2000. The epicenter
was located in New York City with a high level of activity in the immediately
surrounding counties, including Rockland, Westchester, Nassau, and Suffolk.
During 2000, WNV testing was performed by the Wadsworth Center on 3,687 dead
birds, representing 153 species, 46 families, and 18 orders. There were 1,203
WNV-positive birds, representing 63 species, 30 families and 14 orders. The
percentage of WNV-positive birds was 33% for all birds tested throughout the
state, with no significant difference in infection rates in migratory versus
resident birds, although significantly more resident birds were submitted for
testing. The highest apparent mortality for the entire season was observed in
American crows in Staten Island, a location that also showed the highest minimal
infection rate in Culex pipiens complex mosquitoes. Studies examining tissue
tropism of WNV in corvids and noncorvids from the epicenter and from remote
locations indicated that the kidney was the most consistently infected tissue
in birds, regardless of level of infection. The brain was the next most consistently
positive tissue. The differences in infection among the tissues were most apparent
when low levels of virus were present. Experimental mouse inoculation demonstrated
a classical flavivirus infection pattern.
Krenick, F; Jany, W; Clarke, J L 3rd. Sumithrin: from inception
to integration within West Nile virus programs. Annals
of the New York Academy of Sciences. 2001
Dec; 951: 354-6. ISSN: 0077-8923.
NAL Call No.: 500 N484
Descriptors:
Culicidae vector mosquito prevention and control,
insecticides, pyrethrins, efficacy.
Kulas,
K E; Demarest, V L; Franchell, C S; Wong, S J. Use of an
arboviral immunofluorescent assay in screening for West Nile virus.
Annals of the New York Academy of Sciences. 2001 Dec; 951:
357-60. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
fluorescent antibody technique, blood screening
diagnostic test, predictive value of test, immunology, West Nile virus diagnosis,
isolation and purification.
Kulasekera,
V L; Kramer, L; Nasci, R S; Mostashari, F; Cherry, B; Trock, S C; Glaser, C;
Miller, J R. West Nile virus infection in mosquitoes, birds, horses,
and humans, Staten Island, New York, 2000. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 722-5.
ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
disease transition model, Culex pipiens, Culex
restuans, primary enzootic and epizootic vectors among birds, Culex salinariun
as bridge vector for humans, Aedes/Ochlerotatus as bridge vectors for horse
infections.
Abstract:
West Nile (WN) virus transmission
in the United States during 2000 was most intense
on Staten Island, New York, where 10 neurologic illnesses
among humans and 2 among horses occurred. WN virus was isolated from Aedes vexans,
Culex pipiens, Cx. salinarius, Ochlerotatus triseriatus, and Psorophora ferox,
and WN viral RNA was detected in Anopheles punctipennis. An elevated weekly
minimum infection rate (MIR) for Cx. pipiens and increased dead bird density
were present for 2 weeks before the first human illness occurred. Increasing
mosquito MIRs and dead bird densities in an area may be indicators of an increasing
risk for human infections. A transmission model is proposed involving Cx. pipiens
and Cx. restuans as the primary enzootic and epizootic vectors among birds,
Cx. salinarius as the primary bridge vector for humans, and Aedes/Ochlerotatus
spp. as bridge vectors for equine infection.
Lanciotti Robert S; Kerst Amy J; Nasci Roger S; Godsey Marvin S; Mitchell Carl
J; Savage Harry M; Komar Nicholas; Panella Nicholas A; Allen Becky C; Volpe
Kate E; Davis Brent S; Roehrig John T. Rapid detection of
West Nile virus from human clinical specimens, field-collected mosquitoes, and
avian samples by a TaqMan reverse transcriptase-PCR assay.
Journal of Clinical Microbiology.
November, 2001; 38 (11): 4066-4071. ISSN:
0095-1137.
NAL
Call No.: QR46.J6
Descriptors:
rapid TaqMan detection assay, various laboratory
and field tested specimens, comparison, reverse transcriptase PCR assay, virus
isolation in Vero cells, tissues from humans, wild mosquitoes, bird tissues,
surveillance method, surveillance tool, oligonucleotide primers and FAM- and
TAMRA-labeled WN virus-specific probes.
Langevin, S A; Bunning, M; Davis, B; Komar, N. Experimental
infection of chickens as candidate sentinels for West Nile
virus. Emerging Infectious Diseases. 2001
Jul-Aug; 7(4): 726-9. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
duration and level of viremia, serology, chickens,
experimental infections, needle and oral inoculations, sentinel species, antibody
levels, vector mosquitoes.
Abstract:
We
evaluated the susceptibility, duration and intensity of viremia, and serologic
responses of chickens to West Nile (WN) virus (WNV-NY99) infection by needle,
mosquito, or oral inoculation. None of 21 infected chickens developed clinical
disease, and all these developed neutralizing antibodies. Although viremias
were detectable in all but one chicken, the magnitude (mean peak viremia <10,000
PFU/mL) was deemed insufficient to infect vector mosquitoes. WNV-NY99 was detected
in cloacal and/or throat swabs from 13 of these chickens, and direct transmission
of WNV-NY99 between chickens occurred once (in 16 trials), from a needle-inoculated
bird. Nine chickens that ingested WNV-NY99 failed to become infected. The domestic
chickens in this study were susceptible to WN virus infection, developed detectable
antibodies, survived infection, and with one exception failed to infect cage
mates. These are all considered positive attributes of a sentinel species for
WN virus surveillance programs.
Li, W; Brinton, M A. The 3' stem loop of the West Nile virus
genomic RNA can suppress translation of chimeric mRNAs. Virology.
2001 Aug 15; 287(1): 49-61. ISSN: 0042-6822.
NAL
Call No.: 448.8 V81
Descriptors:
viral genetic effects, RNA translation inhibition,
nucleic acid conformation, Northern blotting, ELISA, hamsters. Abstract:
Cis-acting
elements that regulate translation have been identified in the 3' noncoding
regions (NCRs) of cellular and viral mRNAs. As one means of analyzing the effect
on translation of the conserved 3' terminal RNA structure of the West Nile virus
(WNV) genome, the translation efficiencies of chimeric mRNAs composed of a CAT
reporter gene flanked by viral or nonviral 5' and 3' terminal sequences were
compared. In vitro, the WNV 3'(+) stem loop (SL) RNA reduced the translation
efficiencies of chimeric mRNAs with either viral or nonviral 5' NCRs, suggesting
that a specific 3'-5' RNA-RNA interaction was not involved. In contrast, the
3' terminal sequence of a togavirus, rubella virus, enhanced translation efficiency.
The WNV 3'(+)SL reduced translation efficiency both in cis and in trans and
of both capped and uncapped chimeric mRNAs. We have previously reported that
three cellular proteins bind specifically to the WNV 3'(+)SL RNA. Competition
between the WNV 3'(+)SL and the 5' terminus of the chimeric mRNAs for proteins
involved in translation initiation could explain the translation inhibition
observed. Copyright 2001 Academic Press.
Malkinson,
M; Weisman, Y; Pokamonski, S; King, R; Deubel, V. Intercontinental
transmission of West Nile virus by migrating white storks. Emerging
Infectious Diseases. 2001; 7(3 Suppl): 540. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
disease transmission, bird physiology, West
Nile virus dispersion patterns, greographic movement of disease, Europe, Israel, migration birds as disease
reservoirs, storks.
Marfin, A A; Petersen, L R; Eidson, M; Miller, J; Hadler, J; Farello, C; Werner,
B; Campbell, G L; Layton, M; Smith, P; Bresnitz, E; Cartter, M; Scaletta, J;
Obiri, G; Bunning, M; Craven, R C; Roehrig, J T; Julian, K G; Hinten, S R; Gubler,
D J. Widespread West Nile virus activity, eastern United
States, 2000. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 730-5. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
ArboNET, cooperative inter-state surveillance
system, data collection of disease spread in the U.S., animal disease as predictors
of human risks of disease, disease outbreaks, birds, horses, Culicidae mosquitoes,
songbird disease, epidemiology.
Abstract:
In
1999, the U.S. West Nile (WN) virus epidemic was preceded by widespread reports
of avian deaths. In 2000, ArboNET, a cooperative WN virus surveillance system,
was implemented to monitor the sentinel epizootic that precedes human infection.
This report summarizes 2000 surveillance data, documents widespread virus activity
in 2000, and demonstrates the utility of monitoring virus activity in animals
to identify human risk for infection.
McLean, R G; Ubico, S R; Docherty, D E; Hansen, W R; Sileo, L; McNamara, T S.
West Nile virus transmission and ecology in birds. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 54-7. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
captive crows, experimental infection, 1999
NY strain of virus, viremic levels, controls infected by possible oral transmission, direct
transmission.
Abstract:
The
ecology of the strain of West Nile virus (WNV) introduced into the United States
in 1999 has similarities to the native flavivirus, St. Louis encephalitis (SLE)
virus, but has unique features not observed with SLE virus or with WNV in the
old world. The primary route of transmission for most of the arboviruses in
North America is by mosquito, and infected native birds usually do not suffer
morbidity or mortality. An exception to this pattern is eastern equine encephalitis
virus, which has an alternate direct route of transmission among nonnative birds,
and some mortality of native bird species occurs. The strain of WNV circulating
in the northeastern United States is unique in that it causes significant mortality
in exotic and native bird species, especially in the American crow (Corvus brachyrhynchos).
Because of the lack of information on the susceptibility and pathogenesis of
WNV for this species, experimental studies were conducted at the USGS National
Wildlife Health Center. In two separate studies, crows were inoculated with
a 1999 New York strain of WNV, and all experimentally infected crows died. In
one of the studies, control crows in regular contact with experimentally inoculated
crows in the same room but not inoculated with WNV succumbed to infection. The
direct transmission between crows was most likely by the oral route. Inoculated
crows were viremic before death, and high titers of virus were isolated from
a variety of tissues. The significance of the experimental direct transmission
among captive crows is unknown.
Mishra,
A C; Mourya, D T. Transovarial
transmission of West Nile virus in Culex vishnui mosquito. Indian
Journal of Medical Research. 2001 Dec; 114: 212-4. ISSN: 0971-5916.
Descriptors:
Culex vishnui mosquito, biology of transovarial
transmission of West Nile virus, 1st and 2nd gonotropic
cycles, role of mosquito in maintaining population of West Nile virus,
Abstract:
The
phenomenon of transovarial transmission (TOT) of West Nile (WN) virus in Culex
vishnui was studied. The virus was detected in the progeny of both first and
second gonotropic cycles (G1 and G2). About 5.56 per cent pools of F1 progeny
from the parent females infected by the oral route were found positive for WN
virus. This is the first report of TOT of WN virus in this species of mosquito.
The occurrence of this phenomenon is of considerable importance in view of complex
natural cycle of the virus and the high density of this vector species in nature.
The results suggest that this mosquito may be involved in the maintenance of
this virus in nature.
Monath,
TP. Prospects for development of a vaccine against the West Nile virus.
Annals
of the New York Academy of Sciences. 2001 Dec; 951: 1-12. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
feasibility of vaccine development, humans,
horses, formalin inactivated virus-based vaccine, comparison with live attenuated
recombinant vaccine, viron, West Nile virus protein coat.
Abstract:
Vaccination
provides the ultimate measure for personal protection against West Nile disease. The development
of a West Nile vaccine for humans is justified by the uncertainty
surrounding the size and frequency of future epidemics. At least two companies
(Acambis Inc. and Baxter/immuno) have initiated research and development on
human vaccines. West Nile encephalitis has also emerged as a significant
problem for the equine industry. One major veterinary vaccine manufacturer (Ft. Dodge) is developing formalin-inactivated
and naked DNA vaccines. The advantages and disadvantages of formalin-inactivated
whole virion vaccines, Japanese encephalitis vaccine for cross-protection, naked
DNA, and live attenuated vaccines are described. A novel technology platform
for live, attenuated recombinant vaccines (ChimeriVax) represents a promising
approach for rapid development of a West Nile vaccine. This technology
uses yellow fever 17D as a live vector for envelope genes of the West Nile virus. Infectious clone
technology is used to replace the genes encoding the prM and E structural proteins
of yellow fever 17D vaccine virus with the corresponding genes of West Nile virus. The resulting virion
has the protein coat of West Nile, containing all antigenic
determinants for neutralization and one or more epitopes for cytotoxic T lymphocytes.
The genes encoding the nucleocapsid protein, nonstructural proteins, and untranslated
terminal regions responsible for replication remain those of the original yellow
fever 17D virus. The chimeric virus replicates in the host like yellow fever
17D but immunizes specifically against West
Nile
virus.
Morrey
J D; Smee D F; Sidwell R W.
In vitro evaluation of compounds against West
Nile
virus.
Antiviral
Research. April, 2001; 50 (1): A70. ISSN:
0166-3542. Fourteenth International Conference on Antiviral Research, Seattle, Washington, USA, April
08-12, 2001.
NAL
Call No.: QR355.A5
Descriptors:
New York isolate, Vero cell line, anti-viral drugs, 2-thio-6-azauridine enzyme
inhibitor drug, 6-azauridine enzyme inhibitor
drug, GTP synthesis, IMP dehydrogenase,
OMP decarboxylase, TTP synthesis, UTP synthesis, adenosine analogs, cyclopentenylcytosine
[CPE-C] enzyme inhibitor drug, pyrazofurin enzyme inhibitor drug, selenazofurin
enzyme inhibitor drug.
Musa Hindiyeh; Shulman LM; Mendelson E; Weiss L; Grossman Z; Bin H.
Isolation and characterization of West Nile virus from the blood of
viremic patients during the 2000 outbreak in Israel. Emerging
Infectious Diseases. 2001, 7: 4, 748-750; 17 ref. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
viral strain lineages, 1999 New York isolate, Russian isolates,
Israel isolate.
Nasci, R S; Savage, H M; White, D J; Miller, J R; Cropp, B C; Godsey, M S; Kerst,
A J; Bennett, P; Gottfried, K; Lanciotti, R S. West Nile virus in overwintering
Culex mosquitoes, New York City, 2000. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 742-4. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
overwintering adult mosquitoes tested for West
Nile virus, RT PCR, Culex pipiens, vector
mosquitoes in northeastern U.S, Aedes cytology, Vero cells, seasonal effects.
Abstract:
After
the 1999 West Nile (WN) encephalitis outbreak in New York, 2,300 overwintering adult
mosquitoes were tested for WN virus by cell culture and reverse transcriptase-polymerase
chain reaction. WN viral RNA and live virus were found in pools of Culex mosquitoes.
Persistence in overwintering Cx. pipiens may be important in the maintenance
of WN virus in the northeastern United States.
Nasci, R S; White, D J; Stirling, H; Oliver, J A; Daniels, T J; Falco, R C;
Campbell, S; Crans, W J; Savage, H M; Lanciotti, R S; Moore, C G; Godsey, M
S; Gottfried, K L; Mitchell, C J. West Nile virus isolates from mosquitoes
in New York and New Jersey, 1999. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 626-30. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
mosquitoes survival, 24 mosquitoes species,
15 isolates of West Nile virus, main reservoir is Culex pipiens, other Culex
sp, Aedes, Anopheles, Cereopithecus aethiops, viral genetics.
Abstract:
An
outbreak of encephalitis due to West Nile (WN) virus occurred in New York City and the surrounding areas
during 1999. Mosquitoes were collected as part of a comprehensive surveillance
program implemented to monitor the outbreak. More than 32,000 mosquitoes representing
24 species were tested, and 15 WN virus isolates were obtained. Molecular techniques
were used to identify the species represented in the WN virus-positive mosquito
pools. Most isolates were from pools containing Culex pipiens mosquitoes, but
several pools contained two or more Culex species.
Ng,
M L; Tan, S H; Chu, J J.
Transport and budding at two distinct sites of visible nucleocapsids of West
Nile (Sarafend) virus. Journal
of Medical Virology. 2001 Dec; 65(4): 758-64. ISSN:
0146-6615.
Descriptors:
cryo-immunoelectron microscopy, capsid proteins,
neocapsid particles, nucleocapsid physiology, replication cycle, viral envelope
protein analysis, virus ultrastructure, Vero cells.
Abstract:
It
has been difficult to detect and visualize the physical nucleocapsid particles
during the replication process of the flaviviruses. The use of cryo-immunoelectron
microscopy has clearly revealed the capsid proteins and nucleocapsid particles
of West Nile (Sarafend) virus (a flavivirus) for the first time. Physical nucleocapsid
particles accumulated in large numbers from 8 hr postinfection. Double immunolabeling
of the envelope and capsid proteins showed a close association of these structural
proteins for most of the replication cycle. By 10 hr postinfection, budding
of nucelocapsids from the plasma membrane was very obvious. Although maturation
at the plasma membrane was the dominant mode, during late infection, intracellular
maturation into large vacuoles was also observed.
Nolen, R S.
Nation's zoos and aquariums help track West Nile virus. JAMA
-- Journal of the American Veterinary Medical Association. 2001 Nov 15;
219(10): 1327, 1330. ISSN: 0003-1488.
NAL
Call No.: 41.8 Am3
Descriptors:
wild and captive animals susceptibility
to West Nile virus, horses, songbirds, monitoring of disease spread, zoological
parks and aquarium animal collections.
Panella, N A; Kerst, A J; Lanciotti, R S; Bryant, P; Wolf, B; Komar, N.
Comparative West Nile virus detection in organs of naturally infected American
Crows (Corvus brachyrhynchos). Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 754-5. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
West Nile virus disease in birds, deaths of
American crows, levels of virus in various organ tissues, detection in brain
tissue.
Abstract:
Widespread
deaths of American Crows (Corvus brachyrhynchos)were associated with the 1999
outbreak of West Nile (WN) virus in the New York City region. We compared six
organs from 20 crow carcasses as targets for WN virus detection. Half the carcasses
had at least one positive test result for WN virus infection. The brain was
the most sensitive test organ; it was the only positive organ for three of the
positive crows. The sensitivity of crow organs as targets for WN virus detection
makes crow death useful for WN virus surveillance.
Parquet, M C; Kumatori, A; Hasebe, F; Morita, K; Igarashi, A. West Nile
virus-induced bax-dependent apoptosis.
FEBS Letters. 2001 Jun 29; 500(1-2): 17-24. ISSN:
0014-5793.
NAL
Call No.: QD415.F4
Descriptors:
cell lines, K562 and Neuro-2a cells, cell shrinkage,
chromatin concdensation, subdiploid DNA content, DAN destruction, cell wall
membrane changes, viral replication.
Abstract:
The
mechanism of cell death induced by West
Nile
virus (WNV), a causative agent of human febrile syndrome and encephalitis, was
investigated. WNV-infected K562 and Neuro-2a cells manifested the typical features
of apoptosis, including cell shrinkage, chromatin condensation and subdiploid
DNA content by flow cytometry. DNA fragmentation into nucleosomal size and changes
in outer cell membrane phospholipid composition were also observed in K562 cells.
UV-inactivated virus failed to induce the above-mentioned characteristics, suggesting
that viral replication may be required for the induction of apoptosis by WNV.
Additionally, signals involved in WNV-induced apoptosis are associated with
the up-regulation of bax gene expression.
Petersen, L R; Roehrig, J T. West Nile virus: a reemerging
global pathogen. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 611-4. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
zoonotic virus, emerging disease epidemiology,
genetics, virus strains, isolation and purification, viral metabolism, review
article, virulence mutations, Culex mosquitoes, insect vectors, world-wide pathogen
movements.
Petersen LR; Roehrig JT; Petersen LR (ed.); Roehrig JT.
West Nile virus. Emerging
Infectious Diseases. 2001, 7: 4, 611-764. ISSN: 1080-6040. Special issue focusing on West Nile
virus with 30 papers on a variety of topics.
NAL
Call No.: RA648.5 E46
Descriptors:
biology, ecology and epidemiology of West Nile
virus, surveillance systems, disease outbreaks, genetics, Culicidae mosquito
vectors, humans, horses, birds, detection.
Sardelis, M.R.; M. Turell. Ochlerotatus j. japonicus in Frederick County,
Maryland: discovery, distribution, and vector competence for West Nile virus.
Journal of the American Mosquito Control Association. June 2001. v. 17
(2) p. 137-141. ISSN: 8756-971X.
NAL call no: QL536.J686
Descriptors: Culicidae, Aedes albopictus, surveys, oviposition traps,
mosquitoes, geographical distribution, new geographic records, disease vectors,
vector competence, West Nile virus, disseminated infections, disease
transmission, Maryland.
Sardelis, M R; Turell, M J; Dohm, D J; O'Guinn, M L. Vector
competence of selected North American Culex and Coquillettidia mosquitoes for
West Nile virus. Emerging
Infectious Diseases. 2001 Nov-Dec; 7(6): 1018-22.
ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
viral transmission efficiency, vector potential
of various mosquito species, Culex restuans, Culex salinarius, Culex quinquefasciatus,
Culex nigripalpus, Coquillettidia perturbans, chickens, North America.
Abstract:
To control
West Nile virus (WNV), it is necessary
to know which mosquitoes are able to transmit this virus. Therefore, we evaluated
the WNV vector potential of several North American mosquito species. Culex restuans
and Cx. salinarius, two species from which WNV was isolated in New York in 2000,
were efficient laboratory vectors. Cx. quinquefasciatus and Cx. nigripalpus
from Florida were competent but only
moderately efficient vectors. Coquillettidia perturbans was an inefficient laboratory
vector. As WNV extends its range, exposure of additional mosquito species may
alter its epidemiology.
Shi , P Y; Kauffman, E B; Ren, P; Felton, A; Tai, J H; Dupuis, A P 2nd; Jones,
S A; Ngo, K A; Nicholas, D C; Maffei, J; Ebel, G D; Bernard, K A; Kramer, L
D. High-throughput
detection of West Nile virus RNA. Journal
of Clinical Microbiology. 2001 Apr; 39(4): 1264-71.
ISSN:
0095-1137.
NAL
Call No.: QR46.J6
Descriptors:
surveillance protocols, automated RNA extraction, amplification and detection,
robotic system, hight sensitivity method. RT PCR, virus isolation and purification, time factors,
large scale viral RNA surveillance.
Abstract:
The
recent outbreaks of West Nile virus (WNV) in the northeastern
United States and other regions of the
world have made it essential to develop an efficient protocol for surveillance
of WNV. In the present report, we describe a high-throughput procedure that
combines automated RNA extraction, amplification, and detection of WNV RNA.
The procedure analyzed 96 samples in approximately 4.5 h. A robotic system,
the ABI Prism 6700 Automated Nucleic Acid workstation, extracted RNA and set
up reactions for real-time reverse transcription (RT)-PCR in a 96-well format.
The robot extracted RNA with a recovery as efficient as that of a commercial
RNA extraction kit. A real-time RT-PCR assay was used to detect and quantitate
WNV RNA. Using in vitro transcribed RNA, we estimated the detection limit of
the real-time RT-PCR to be approximately 40 copies of RNA. A standard RT-PCR
assay was optimized to a sensitivity similar to that of the real-time RT-PCR.
The standard assay can be reliably used to test a small number of samples or
to confirm previous test results. Using internal primers in a nested RT-PCR,
we increased the sensitivity by approximately 10-fold compared to that of the
standard RT-PCR. The results of the study demonstrated for the first time that
the use of an automated system for the purpose of large-scale viral RNA surveillance
dramatically increased the speed and efficiency of sample throughput for diagnosis.
Sibbald, B.
Quebec clears way for use of aerial pesticides to combat West Nile virus.
Canadian
Medical Association Journal . 2001
Aug 21; 165(4): 463. ISSN:
0820-3946.
NAL
Call No.: R11 C3
Descriptors:
Canada, disease prevention, arial
spraying for mosquito control, malathion, administration
and dosages, adverse effects, birds, Quebec.
Snook, C.S.; S. Hyman; F. Del Piero; J. Palmer; E. Ostlund; B. Barr; A. Desrochers;
L. Reilly. West Nile virus encephalomyelitis in eight horses. Journal
of the American Veterinary Medical Association. May 15, 2001. v. 218 (10)
p. 1576-1579. ISSN: 0003-1488.
NAL call no: 41.8 Am3
Descriptors: horses, West Nile virus, West Nile fever, encephalitis,
symptoms, clinical aspects, diagnosis, treatment, prognosis, case reports, New
York, New Jersey.
SoRelle, R.
West Nile virus spreading.
Circulation.
2001
Aug 14; 104(7): E9011-3 ISSN: 1524-4539.
Descriptors:
epidemiology, transmission, virus isolation and
purification, disease spread, implication for prevention and control.
Swayne, D E; Beck, J R; Smith, C S; Shieh, W J; Zaki, S R.
Fatal encephalitis and myocarditis in young domestic geese (Anser anser domesticus)
caused by West Nile virus. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 751-3. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
experimental infection, young geese, effects
of disease on geese, clinical signs, possible reservoir for the virus, mosquito
vector.
Abstract:
During
1999 and 2000, a disease outbreak of West Nile (WN) virus occurred in humans,
horses, and wild and zoological birds in the northeastern USA. In our experiments, WN
virus infection of young domestic geese (Anser anser domesticus) caused depression,
weight loss, torticollis, opisthotonus, and death with accompanying encephalitis
and myocarditis. Based on this experimental study and a field outbreak in Israel, WN virus is a disease
threat to young goslings and viremia levels are potentially sufficient to infect
mosquitoes and transmit WN virus to other animal species.
Trock, S C; Meade, B J; Glaser, A L; Ostlund, E N; Lanciotti, R S; Cropp, B
C; Kulasekera, V; Kramer, L D; Komar, N. West
Nile virus outbreak among horses in New York State, 1999 and 2000.
Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 745-7. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
humans/horses disease correlations, epidemiology,
Culex mosquitoes species as disease vectors, physiopathology, Aedes, disease
pathology, viral genetics, immunology, RT PCR, New York State.
Abstract:
West Nile (WN) virus was identifiedin
the Western Hemisphere in 1999. Along with human
encephalitis cases, 20 equine cases of WN virus were detected in 1999 and 23
equine cases in 2000 in New York. During both years, the equine cases occurred
after human cases in New York had been identified.
Turell, M J; Sardelis, M R; Dohm, D J; O'Guinn, M L.
Potential North American vectors of West Nile virus. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 317-24.ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
vector efficiency testing, Culex pipiens, Culex
nigripalpus, Culex quinquefasciatus, Culex salinarius, Aedes albopictus, Aedes
vexans, Ochlerotatus japonicus, Ochlerotatus sollicitans, Ochlerotatus taeniorhynchus,
and Ochlerotatus triseriatus, mosquito from inoculated chicks, environmental
factors, populations, lifespan, mosquito feeding habits.
Abstract:
The
outbreak of disease in the New York area in 1999 due to West
Nile (WN) virus was the first evidence of the occurrence of this virus in the
Americas. To determine potential
vectors, more than 15 mosquito species (including Culex pipiens, Cx. nigripalpus,
Cx. quinquefasciatus, Cx. salinarius, Aedes albopictus, Ae. vexans, Ochlerotatus
japonicus, Oc. sollicitans, Oc. taeniorhynchus, and Oc. triseriatus) from the
eastern United States were evaluated for their ability to serve as vectors for
the virus isolated from birds collected during the 1999 outbreak in New York.
Mosquitoes were allowed to feed on one- to four-day old chickens that had been
inoculated with WN virus 1-3 days previously. The mosquitoes were incubated
for 12-15 days at 26 degrees C and then allowed to refeed on susceptible chickens
and assayed to determine transmission and infection rates. Several container-breeding
species (e.g., Ae. albopictus, Oc. atropalpus, and Oc. japonicus) were highly
efficient laboratory vectors of WN virus. The Culex species were intermediate
in their susceptibility. However, if a disseminated infection developed, all
species were able to transmit WN virus by bite. Factors such as population density,
feeding preference, longevity, and season of activity also need to be considered
in determining the role these species could play in the transmission of WN virus.
Turell, M.J.; M. O'Guinn; D. Dohm; J. Jones. Vector competence of North
American mosquitoes (Diptera: Culicidae) for West Nile virus. Journal
of Medical Entomology. Mar 2001. v. 38 (2) p. 130-134. ISSN: 0022-2585.
NAL call no: 421 J828
Descriptors: Aedes aegypti, Aedes albopictus, Aedes atropalpus, Aedes
japonicus, Aedes sollicitans, Aedes taeniorhynchus, Aedes vexans, Culex
pipiens, West Nile virus, susceptibility, disseminated infections, disease
vectors, vector competence, disease transmission, New York City, Virginia,
North America.
Abstract: We evaluated the potential for several North American
mosquito species to transmit the newly introduced West Nile (WN) virus.
Mosquitoes collected in the New York City metropolitan area during the
recent WN virus outbreak, at the Assateague Island Wildlife Refuge, VA, or
from established colonies were allowed to feed on chickens infected with
WN virus isolated from a crow that died during the 1999 outbreak. These
mosquitoes were tested approximately equal to 2 wk later to determine
infection, dissemination, and transmission rates. Aedes albopictus
(Skuse), Aedes atropalpus (Coquillett), and Aedes japonicus (Theobald)
were highly susceptible to infection, and nearly all individuals with a
disseminated infection transmitted virus by bite. Culex pipiens L. and
Aedes sollicitans (Walker) were moderately susceptible. In contrast, Aedes
vexans (Meigen), Aedes aegypti (L.), and Aedes taeniorhynchus (Wiedemann)
were relatively refractory to infection, but individual mosquitoes
inoculated with WN virus did transmit virus by bite. Infected female Cx.
pipiens transmitted WN virus to one of 1,618 F1 progeny, indicating the
potential for vertical transmission of this virus. In addition to
laboratory vector competence, host-feeding preferences, relative
abundance, and season of activity also determine the role that these
species could play in transmitting WN virus.
Tyler, KL.
West Nile virus encephalitis in America. New
England Journal of Medicine. 2001 Jun 14; 344(24): 1858-9.
ISSN: 0028-4793.
NAL
Call No.: 448.8 N442
Descriptors:
disease outbreaks, New York City, epidemiology, virus isolation,
PCR, surveillance, diagnosis, transmission.
Wang, T; Anderson, J F; Magnarelli, L A; Bushmich, S; Wong, S; Koski, R A; Fikrig,
E. West
Nile virus envelope protein: role in diagnosis and immunity. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 325-7. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
antibodies, viral envelope proteins, diagnosis,
immunology, inbred C3H mice, recombinant
proteins immunology, level of protection, passive immunization, rabbits, mice,
diagnostic aid.
Abstract:
The
role of antibodies to the West Nile virus envelope (E) protein
in serodiagnosis and protection was examined. The E protein was expressed and
purified in recombinant form. Antibodies to the E protein were detected in patients
with West Nile virus infection. Passive immunization with rabbit anti-E protein
sera also partially protected mice from challenge with West Nile virus. The
humoral response to the West Nile virus E protein is therefore
useful as an aid in the diagnosis and may also play a role in immunity to infection.
Wang, T; Anderson, J F; Magnarelli, L A; Wong, S J; Koski, R A; Fikrig, E.
Immunization of mice against West Nile virus with recombinant envelope protein.
Journal
of Immunology. 2001
Nov 1; 167(9): 5273-7. ISSN:
0022-1767.
Descriptors:
recombinant envelope protein, C3H/HeN mice, immunized with E protein, antibody
development, level of protection, possible immunization potential for a vaccine.
Abstract:
West Nile (WN) virus is a mosquito
borne flavivirus that emerged in the United States in 1999 and can cause
fatal encephalitis. Envelope (E) protein cDNA from a WN virus isolate recovered
from Culex pipiens in Connecticut was expressed in Escherichia coli. The recombinant
E protein was purified and used as Ag in immunoblot assays and immunization
experiments. Patients with WN virus infection had Abs that recognized the recombinant
E protein. C3H/HeN mice immunized with E protein developed E protein Abs and
were protected from infection with WN virus. Passive administration of E protein
antisera was also sufficient to afford immunity. E protein is a candidate vaccine
to prevent WN virus infection.
White, DJ.
Vector surveillance for West Nile virus. Annals
of the New York Academy of Sciences. 2001 Dec; 951: 74-83. ISSN:
0077-8923.
NAL Call No.: 500 N484
Descriptors:
mosquito and West Nile virus surveillance programs,
response plan, vector population data, movement of 8 mosquito species, control efficacy, public health concerns, epidemiology,
New York State, Culicidae, sentinel surveillance, virus genetics.
Abstract:
West Nile virus (WNV) was detected
in the metropolitan New York City (NYC) area during the summer and fall of 1999.
Sixty-two human cases, including seven fatalities, were documented. The New
York State Department of Health (NYSDOH) initiated and implemented a statewide
mosquito and WNV surveillance system. We developed a WNV response plan designed
to provide local health departments (LHD) a standardized means to begin to assess
basic mosquito population data and to detect WNV circulation in mosquito populations.
During the 2000 arbovirus surveillance season, local health agencies collected
317,676 mosquitoes and submitted 9,952 pools for virus testing. NYSDOH polymerase
chain reaction (PCR) testing detected 363 WNV-positive pools. Eight species
of mosquitoes were found to be infected. Of the 26 counties conducting mosquito
surveillance, WNV-positive mosquitoes were detected only in NYC, on Long Island,
and in four counties in the lower Hudson River valley region. LHD larval surveillance
provided initial or enhanced mosquito habitat location and characterization
and mosquito species documentation. Adult mosquito surveillance provided LHD
information on species' presence, density, seasonal fluctuations, virus infection,
minimum infection ratios (MIR) and indirect data on mosquito control efficacy
after larval or adult control interventions. Collective surveillance activities
conducted during 1999 and 2000 suggest that WNV has dispersed throughout the
state and may affect local health jurisdictions within NYS, adjacent states,
and Canada in future years. Vector surveillance will remain a critical component
of LHD programs addressing public health concerns related to WNV.
White, D J; Kramer, L D; Backenson, P B; Lukacik, G; Johnson, G; Oliver, J A;
Howard, J J; Means, R G; Eidson, M; Gotham, I; Kulasekera, V; Campbell, S.
Mosquito surveillance and polymerase chain reaction detection of West Nile virus,
New York State. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 643-9. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
state-wide mosquito and virus surveillance system,
8 species as disease vectors, exposure risks, PCR testing to confirm the virus,
human exposure risks, New York State.
Abstract:
West
Nile (WN) virus was detected in the metropolitan New York City (NYC) area during
the summer and fall of 1999. Sixty-two human cases, 7 fatal, were documented.
The New York State Department of Health initiated a departmental effort to implement
a statewide mosquito and virus surveillance system. During the 2000 arbovirus
surveillance season, we collected 317,676 mosquitoes, submitted 9,952 pools
for virus testing, and detected 363 WN virus-positive pools by polymerase chain
reaction (PCR). Eight species of mosquitoes were found infected. Our mosquito
surveillance system complemented other surveillance systems in the state to
identify relative risk for human exposure to WN virus. PCR WN virus-positive
mosquitoes were detected in NYC and six counties in the lower Hudson River Valley
and metropolitan NYC area. Collective surveillance activities suggest that WN
virus can disperse throughout the state and may impact local health jurisdictions
in the state in future years.
Xiao, S Y; Guzman, H; Zhang, H; Travassos da Rosa, A P; Tesh, R B.
West Nile virus infection in the golden hamster (Mesocricetus auratus):
a model for West Nile encephalitis. Emerging
Infectious Diseases. 2001 Jul-Aug; 7(4): 714-21. ISSN: 1080-6040.
NAL
Call No.: RA648.5 E46
Descriptors:
animal disease model, golden hamsters, New York isolate, levels of viremia,
antibody responses, symptoms of disease, viral persistence pathogenesis.
Abstract:
This report describes a new hamster model for
West Nile (WN) virus encephalitis. Following intraperitoneal inoculation of
a New York isolate of WN virus, hamsters had moderate viremia of 5 to 6 days
in duration, followed by the development of humoral antibodies. Encephalitic
symptoms began 6 days after infection; about half the animals died between the
seventh and 14th days. The appearance of viral antigen in the brain and neuronal
degeneration also began on the sixth day. WN virus was cultured from the brains
of convalescent hamsters up to 53 days after initial infection, suggesting that
persistent virus infection occurs. Hamsters offer an inexpensive model for studying
the pathogenesis and treatment of WN virus encephalitis.
Yang, J S; Kim, J J; Hwang, D; Choo, A Y; Dang, K; Maguire,-H; Kudchodkar, S;
Ramanathan, M P; Weiner, D B. Induction of potent Th1-type immune responses
from a novel DNA vaccine for West Nile virus New York isolate (WNV-NY1999).
Journal of Infectious Diseases. 2001
Oct 1; 184(7): 809-16. ISSN: 0022-1899.
Descriptors:
DNA vaccine development, encoded West Nile virus
capsid protein, mouse model, muscle injections, humoral/cellular responses,
lumphocyte responses, T-cells, macrophages, potential use as vaccine evaluated.
Abstract:
West Nile virus (WNV) is a vectorborne
pathogen that induces brain inflammation and death. Recently, confirmed cases
of infection and deaths have occurred in the United States Mid-Atlantic region.
In this study, a DNA vaccine encoding the WNV capsid protein was constructed,
and the in vivo immune responses generated were investigated in DNA vaccine-immunized
mice. Antigen-specific humoral and cellular immune responses were observed,
including a potent induction of antigen-specific Th1 and cytotoxic T lymphocyte
responses. Strong induction of Th1-type immune responses included high levels
of antigen-specific elaboration of the Th1-type cytokines interferon-gamma and
interleukin-2 and beta-chemokines RANTES (regulated upon activation, normal
T cell-expressed and secreted) and macrophage inflammatory protein-1beta. Dramatic
infiltration of CD4 and CD8 T cells and macrophages also was observed at the
muscle injection site. These results support the potential utility of this method
as a tool for developing immunization strategies for WNV and other emerging
pathogens.
Zeller, HG; Murgue,
B. Role des oiseaux migrateurs dans l'epidemiologie du virus
West Nile. [The role of migrating
birds in the West
Nile
virus epidemiology.] 10e
Colloque sur le controle epidemiologique des maladies infectieuses (CEMI): Epidemiologie,
surveillance et prevention des zoonoses, 4 mai 2001, Institut Pasteur, Paris, France.
Medecine-et-Maladies-Infectieuses.
2001, 31: Supplement2, 168s-174s; 27 ref. ISSN: 0399-077X. In French with
an English summary.
Descriptors:
West Nile virus outbreaks, transmission cycle,
epidemiology, movement of disease via migrating birds, factors supporting outbreaks,
disease vectors, humans, horses, Culex mosquitoes as disease vectors, susceptible
birds, Europe, Africa.
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February 6, 2003