Anonymous.  West Nile virus and other exotic diseases of horses.  Australian Veterinary Journal.  2003 Aug; 81(8): 456-457.  ISSN: 0005-0423. 

NAL call no.: 41.8 AU72

Descriptors:  horses, exotic diseases, West Nile virus, clinical signs, background on virus, birds as disease reservoirs, surveillance and prevention, sentinel birds, mosquitoes as vectors, viral host range, differential diagnosis, horse mortality, progress of WNV across the United States.


Bren, L.  West Nile virus: reducing the risk.  FDA Consumer.  2003 Jan/Feb; 37(1): 20-27.  ISSN: 0362-1332. URL: http://www.fda.gov/fdac/fdacindex.html

NAL call no.: HD9000.9.U5A1

Descriptors:  West Nile virus, disease prevention, disease vectors, vector control, mosquito-borne diseases, Culex pipiens, several modes of disease transmission, birds, blood transfusion, human breast milk, breast feeding, medical treatment, public health, disease control.


Brown, D.  Is the Clean Water Act swamping mosquito control efforts against West Nile virus?  Journal of the American Mosquito Control Association.  2003 Dec; 19(4): 283-285.  ISSN: 8756-971X.

NAL call no.: QL536.J686

Descriptors:  West Nile virus, viral diseases of animals and humans, mosquito control; trade associations, information exchange, Clean Water Act, water pollution, pollution control, environmental impact, insect vectors, vector control, public health.


Davis, C. Todd; Beasley, David W.C.; Guzman, Hilda; Raj, Rushker; D'Anton, Mary; Novak, Robert J.; Unnasch, Thomas, R.; Tesh, Robert B.; Barrett, Alan D.T.  Genetic variation among temporally and geographically distinct West Nile virus isolates, United States, 2001, 2002.  Emerging Infectious Diseases.  2003 Nov; 9(11): 1423-1429.  ISSN: 1080-6040. 

NAL call no.:  RA648.5.E46

Descriptors:  West Nile virus isolates, partial nucleotide sequence of isolates, reverse transcriptase polymerase chain reaction, shared and divergent nucleotide mutations, geographic clustering, dominant variant.

Abstract:  Analysis of partial nucleotide sequences of 22 West Nile virus (WNV) isolates collected during the summer and fall of 2001 and 2002 indicated genetic variation among strains circulating in geographically distinct regions of the United States and continued divergence from isolates collected in the northeastern United States during 1999 and 2000.  Sequence analysis of a 2,004-nucleotide region showed that 14 isolates shared two nucleotide mutations and one amino acid substitution when they were compared with the prototype WN-NY99 strain, with 10 of these isolates sharing an additional nucleotide mutation.  In comparison, isolates collected from coastal regions of southeast Texas shared the following differences from WN-NY99: five nucleotide mutations and one amino acid substitution.  The maximum nucleotide divergence of the 22 isolates from WN-NY99 was 0.35% (mean = 0.18%).  These results show the geographic clustering of genetically similar WNV isolates and the possible emergence of a dominant variant circulating across much of the United States during 2002.


Estrada-Franco, Jose G.; Navarro-Lopez, Roberto; Beasley, David W.C.; Coffey, Lark; Carrara, Anne-Sophie; Travassos da Rosa, Amelia; Clements, Tamara; Wang, Eryu; Ludwig, George V.; Cortes, Arturo, Campomanes; Ramirez, Pedro Paz; Tesh, Robert B.; Barrett, Alan D.T.; Weaver, Scott C.  West Nile virus in Mexico: evidence of widespread circulation since July 2002.  Emerging Infectious Diseases.  2003 Dec; 9(12): 1604-1607.  ISSN: 1080-6040. 

NAL call no.: RA639.5.V43

Descriptors:  horses, a common raven, epidemiology, enzyme-linked immunosorbent assay, hemagglutination inhibition tests, transcriptase polymerase chain reaction, nucleic acid sequence analysis, seroepidemiology, antibodies, first isolates in Mexico.

Abstract:  West Nile virus (WNV) antibodies were detected in horses from five Mexican states, and WNV was isolated from a Common Raven in the state of Tabasco.  Phylogenetic studies indicate that this isolate, the first from Mexico, is related to strains from the central United States but has a relatively high degree of sequence divergence.


Fernandez-Salas, Ildefonso; Contreras-Cordero, Juan F.; Blitvich, Bradley J.; Gonzalez-Rojas, Jose I.; Cavazos-Alvarez, Amanda; Marlenee, Nicole L.; Elizondo-Quiroga, Armando; Lorono-Pino, Maria A.; Gubler, Duane J.; Cropp, Bruce C.; Calisher, Charles H.; Beaty, Barry.  Serologic evidence of West Nile virus infection in birds, Tamaulipas State, Mexico.  Vector Borne and Zoonotic Diseases.  2003 Winter; 3(4): 209-213.  ISSN: 1530-3667.  

NAL call no.: RA639.5.V43 

Descriptors:  West Nile virus infected birds, flavivirus-specific antibodies, enzyme-linked immunosorbent assay, plaque reduction neutralization tests, seroepidemiology, first indirect evidence of WNV in northern Mexico birds.

Abstract:  Following the introduction of West Nile virus (WNV) into North America in 1999, surveillance for WNV in migratory and resident birds was established in Tamaulipas State, northern Mexico in December 2001.  Overall, 796 birds representing 70 species and 10 orders were captured and assayed for antibodies to WNV. Nine birds had flavivirus-specific antibodies by epitope-blocking enzyme-linked immunosorbent assay; four were confirmed to have antibody to WNV by plaque reduction neutralization test.  The WNV-infected birds were a house wren, mourning dove, verdin and Bewick's wren.  The house wren is a migratory species; the other WNV-infected birds are presumably residents.  The WNV-infected birds were all captured in March 2003.  These data provide the first indirect evidence of WNV transmission among birds in northern Mexico.


Goddard, L.B.; Roth, A.E.; Reisen, W.K.; Scott, T.W.  Vertical transmission of West Nile virus by three California Culex (Diptera: Culicidae) species.  Journal of Medical Entomology.  2003 Nov; 40(6): 743-746.  ISSN: 0022-2585.

NAL call no.: 421 J828

Descriptors:  Culex pipiens pipiens L., Culex pipiens quinquefasciatus Say, Culex tarsalis, intrathoracic WNV experimental inoculation, filial infection rate, potential mechanism of horizontal transmission.

Abstract:  Three California Culex species previously identified as efficient laboratory vectors of West Nile (WN) virus were tested for their capability to vertically transmit WN virus.  Wild-caught Culex pipiens pipiens L., Culex pipiens quinquefasciatus Say, and two populations of Culex tarsalis Coquillett females were inoculated intrathoracically with 10(2.7 (+/-) 0.1) plaque-forming units of WN virus. F1 progeny were reared at 18 C and subsequently tested as adults for infectious virus on Vero cell culture.  Virus was not detected in 197 pools comprising 4,884 Cx. p. pipiens.  The minimum filial infection rate (MFIR) for Cx. p. quinquefasciatus was approximately 3.0/1,000 for 665 progeny tested in 28 pools. There was no virus detected in 102 pools of 2,453 progeny from Cx. tarsalis collected in Riverside County.  The MFIR for Cx. tarsalis collected in Yolo County was approximately 6.9/1,000 for 2,165 progeny tested in 86 pools.  Mosquito progeny infected vertically during the fall could potentially serve as a mechanism for WN virus to overwinter and initiate horizontal transmission the following spring.


Guthrie, A.J.  Howell, P.G.; Gardner, I.A.; Swanepoel, R.E.; Nurton, J.P.; Harper, C.K.; Pardini, A.; Groenewald, D.; Visage, C.W.; Hedges, J.F.  West Nile virus infection of Thoroughbred horses in South Africa (2000-2001). Equine Veterinary Journal.  Sept 2003 Sept; 35(6): 601-605.  ISSN: 0425-1644. 

NAL call no.: SF955.E6

Descriptors:  thoroughbred horses, West Nile virus, disease transmission, seroprevalence, epidemiology.


Holger, Breithaupt.  Aliens on the shores.  EMBO Reports (England).  2003 Jun; 4(6): 547-550.  ISSN: 1469-221X . 

NAL call no. QH506.E463

Descriptors:  West Nile virus, animals, beetles, turtles, biodiversity, ecosystem, conservation of natural resources, population dynamics, green algae, Mediterranean Sea, New York, United States.


Jozan, M.; Evans, R.; McLean, R.; Hall, R.; Tangredi, B.; Reed, L.; Scott, J.  Detection of West Nile virus infection in birds in the United States by blocking ELISA and immunohistochemistry.  Vector Borne and Zoonotic Diseases. 2003 Fall; 3(3): 99-110.  ISSN: 1530-3667.  

NAL call no.: RA639.5.V43

Descriptors:  viral diseases of animals and humans, wild birds, chickens, sentinel animals, ducks, Anas platyrhynchos West Nile virus, disease detection, antibody detection, ELISA, antigen detection, immunohistochemistry, disease prevalence, disease surveillance.


Kent, R.J.; Lacer, L.D.; Meisch, M.V.  Initiating arbovirus surveillance in Arkansas, 2001.  Journal of Medical Entomology.  2003 Mar; 40(2): 223-229.  ISSN: 0022-2585. 

NAL call no.: 421 J828

Descriptors:  mosquitos, Culicidae, wild birds, cooperative arbovirus surveillance, dead bird passive surveillance, horses, equine encephalitis virus, Eastern and Western equine encephalitis virus, St Louis encephalitis virus, first reported incidence of West Nile virus in Arkansas.

Abstract:  Migratory birds could introduce West Nile (WN) virus to Arkansas.  The purpose of this study was to establish a cooperative arbovirus surveillance program to monitor mosquitoes and birds in Arkansas for arboviruses. Our objectives were to: 1) perform routine, multicounty collections of mosquitoes and test them for eastern equine encephalitis, St. Louis encephalitis, and WN viruses; and 2) conduct passive surveillance by testing dead wild birds for WN virus.  Arbovirus surveillance was organized by the Arkansas Department of Health, University of Arkansas, and Vector Disease Control Incorporated.  None of the 14,560 mosquitoes (425 pools) tested were virus positive.  Two hundred forty-two dead birds from 62 counties were tested for WN virus.  Four blue jays in three counties were positive.  These infections are the first reported incidences of WN virus in Arkansas.  Sera from five horses with suspected encephalitis all tested negative for WN, eastern equine encephalitis, and western equine encephalitis viruses.


Kiupel, M.; Simmons, H.A.; Fitzgerald, S.D.; Wise, A.; Sikarskie, J.G.; Cooley, T.M.; Hollamby, S.R.; Maes, R. West Nile virus infection in Eastern fox squirrels (Sciurus niger).  Veterinary Pathology.  2003 Nov; 40(6): 703-707. ISSN: 0300-9858. 

NAL call no.: 41.8 P27

Descriptors:  first report of West Nile virus infected squirrels, Sciuridae, pathology, microscopic leisions of brain kidney heart and liver, immunohistochemistry, reverse transcriptase polymerase chain reaction (RT-PCR).

Abstract:  Since the initial outbreak of West Nile virus (WNV) in the northeastern United States in 1999, the virus has rapidly spread westward and southward across the USA, causing high mortality in crows as well as sporadic mortality in horses, humans, and a wide variety of birds.  In 2002 the epidemic widened as hundreds of equine and human cases and sporadic cases in other mammalian species were reported. This is the first report of WNV infection in three Eastern fox squirrels (Sciurus niger).  Neurologic signs included head tilt, uncoordinated movement, paralysis, and tremors.  Gross lesions were absent. Microscopic lesions consisted of lymphoplasmacytic inflammation involving the brain, heart, kidney, and liver.  Formalin-fixed tissues from the three squirrels were tested for WNV antigen by immunohistochemical staining and for WNV-specific RNA by reverse transcriptase-polymerase chain reaction (RT-PCR).  The kidneys of all three squirrels stained positive with immunohistochemistry for WNV, whereas the brain and heart were positive in only one animal.  Two of the three squirrels were positive for WNV by RT-PCR.


Lanciotti, Robert S.  Molecular amplification assays for the detection of flaviviruses.  Advances in Virus Research. 2003; 61: 67-99.  ISSN: 0065-3527.  

NAL call no.:  448.8 AD9

Descriptors:  flavivirus assay format description, flavivirus assay utility, reverse transcriptase-polymerase chain reaction, fluorescent-labeled probes (TaqMan), nucleic acid sequence based amplification (NASBA).

Abstract:  Over the past 10 years, a number of molecular amplification assays have been developed for the detection of flaviviruses. Most of these assays utilize the reverse transcriptase-polymerase chain reaction (RT-PCR) as the amplification format with detection by either agarose gel electrophoresis and ethidium bromide staining or hybridization with molecular probes. Recently, a modification of the standard RT-PCR using fluorescent-labeled oligonucleotide probes for detection (TaqMan) has been described.  As a result, several assays for detecting flaviviruses have been developed using this approach. In addition, another amplification format, nucleic acid sequence based amplification (NASBA), has been developed and utilized for the detection of several flaviviruses.  The various assay formats will be described and their utility discussed. 


Nasci, R.S. Gottfried, K.L.; Burkhalter, K.L.; Ryan, J.R.; Emmerich, E.; Dave, K.  Sensitivity of the VecTest antigen assay for eastern equine encephalitis and western equine encephalitis viruses.  Journal of the American Mosquito Control Association.  2003 Dec; 19(4): 440-444.  ISSN: 8756-971X.  

NAL call no.: QL536.J686.

Descriptors:  Eastern equine encephalitis virus, Western equine encephalitis virus, Saint Louis encephalitis virus, West Nile virus, viral antigens, antigen detection, immunoassay, rapid methods, insect vectors, mosquitoes, disease surveillance, Eastern equine encephalomyelitis, Western equine encephalomyelitis, dipstick immunoassay.


Peterson, A.T.; Vieglais, D.A.; Andreasen, J.K.  Migratory birds modeled as critical transport agents for West Nile virus in North America.  Vector Borne and Zoonotic Diseases.  2003 Spring; 3(1): 27-37.  ISSN: 1530-3667.

NAL call no.: RA639.5.V43

Descriptors:  disease reservoirs, wild birds, seasonal migration, Culex, mosquitoes, disease vectors, geographical distribution, simulation models, insect ecology, virus transmission, mathematical models, prediction, epidemiology, vector ecology, ecological niche modeling, Genetic Algorithm for Rule-set Prediction (GARP), New York City.


Pisarev, V.B.; Shishkina, E.O.; Larichev, V.F.; Grigor'eva, N.V.  Morphofunctional characteristics of antigen-presenting cells in lymph node in mice with experimental West Nile fever.  Bulletin of Experimental Biology and Medicine.  2003 Mar; 135(3): 293-295.  ISSN: 0007-4888. 

NAL call no.: 442.8 B87AE

Descriptors:  albino mice experimentally infected, West Nile fever (986) changed cells in mesenteric lymph nodes.

Abstract:  Pronounced transformation of cells in mesenteric lymph nodes, mainly in the thymus-independent zone and sinuses, was detected in albino mice experimentally infected with West Nile fever (strain 986). Maximum antigen-presenting activity was exhibited by activated macrophages, minimum activity--by dendritic cells of lymphoid follicles.


Putnak, Robert; Porter, Kevin; Schmaljohn, Connie.  DNA vaccines for flaviviruses.  Advances in Virus Research. 2003; 61: 445-68.  ISSN: 0065-3527.  

NAL call no.: 448.8 AD9

Descriptors:  animals, flavivirus, immunology, vaccines, DNA, isolation and purification, viral vaccines, animals, Dengue virus, genetics and immunology, tick-borne encephalitis viruses genetics and immunology, infections, Japanese Encephalitis vaccines, genetics, isolation and purification, West Nile virus.


Ryan, J.; Dave, K.; Emmerich, E.; Fernandez, B.; Turell, M.; Johnson, J.; Gottfried, K.; Burkhalter, K.; Kerst, A.; Hunt, A. Wicking assays for the rapid detection of West Nile and St. Louis encephalitis viral antigens in mosquitoes (Diptera: Culicidae).  Journal of Medical Entomology.  2003 Jan; 40(1): 95-99.  ISSN: 0022-2585. 

NAL call no.: 421 J828

Descriptors:  Aedes aegypti, Culex pipiens, West Nile virus, St Louis encephalitis virus, arbovirus antigen rapid detection methods, differentiating field assays, dipstick assay, immunochromatography (VecTest), vector surveillance, rapid medical threat assessment.

Abstract:  The recent outbreaks of West Nile (WN) encephalitis and St. Louis encephalitis (SLE) in the United States have highlighted the need for rapid and specific methods of detecting arboviral antigens in mosquitoes.  We evaluated rapid, field-usable assays for detecting and differentiating WN and SLE viruses in mosquito pools, based on a patent-pending, immunochromatographic technology (VecTest) formatted on a dipstick.  The device provides results in less than 20 min and can be used in laboratories with adequate containment facilities.  In laboratory assessments, both the SLE and WN virus tests demonstrated sensitivity comparable with that of an antigen capture ELISA, but less than can be achieved with Vero cell plaque or reverse-transcriptase polymerase chain reaction assays.  There was no evidence of cross-reaction when tested with high concentrations of heterologous flavivirus antigens or with Eastern equine encephalitis or Western equine encephalitis viruses.  Both the WN and SLE dipstick tests delivered a clear positive result with a single positive specimen in a pool of 50 mosquitoes.  This virus assay technology reduces the time required to obtain test results and will allow rapid medical threat assessment and effective targeting of vector control measures.


Takasaki, Tomohiko; Yabe, Sadao; Nerome, Reiko; Ito, Mikako; Yamada, Ken-Ichiro; Kurane, Ichiro.  Partial protective effect of inactivated Japanese encephalitis vaccine on lethal West Nile virus infection in mice. Vaccine.  2003 Nov; 21(31): 4514-4518.  ISSN: 0264-410X. 

NAL call no.: QR189.V32

Descriptors:  mouse brain-derived Japanese Encephalitis (JE) vaccine, murine model, JE immunized mice challenged with West Nile virus (WNV), intracranial challenge, intraperitoneal challenge, partial immunity in mice.

Abstract:  The effect of mouse brain-derived, inactivated Japanese encephalitis (JE) vaccine on West Nile virus (WNV) infection was examined using a murine model.  Mice were immunized with JE vaccine twice and challenged with lethal doses of WNV.  When mice were intracranially challenged with WNV, none of the immunized mice were protected.  When mice were intraperitoneally challenged, the immunized mice were protected at higher immunization levels.  Cross-reactive neutralizing antibodies to WNV were induced by immunization with JE vaccine; however, the levels were much lower than those to JEV.  These results indicate that the currently available mouse brain-derived inactivated JE vaccine can induce partial protective immunity to WNV in mice.


United States. Animal and Plant Health Inspection Service. Veterinary Services. Centers for Epidemiology and Animal Health. Equine West Nile virus outlook for the United States.  APHIS Veterinary Services Info Sheet. 2003; Note: 1 folded sheet ([4] p.), map, 28 cm.

URL: http://www.aphis.usda.gov/vs/ceah/cahm/Equine/WNV.pdf

NAL call no.: aSF959.V57E26 2003

Descriptors:  horses, West Nile virus, economic impact, equine industries, Colorado, Nebraska. 

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December 15, 2004