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You are here: Home / Publications / Bibliographies and Resource Guides / West Nile Virus Bibliography, 2004 -2007 / West Nile Virus Associated Diseases  Printer Friendly Page
West Nile Virus Bibliography, 2004-2007
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 West Nile Virus Associated Diseases

Abroug, F., L. Ouanes Besbes, M. Letaief, F. Ben Romdhane, M. Khairallah, H. Triki, and N. Bouzouiaia (2006). A cluster study of predictors of severe West Nile virus infection. Mayo Clinic Proceedings 81(1): 12-16.
Abstract: OBJECTIVE: To assess the value of multifocal chorioretinitis and of clinical manifestations and biologic parameters in the diagnosis of West Nile virus (WNV) infection. PATIENTS AND METHODS: We conducted a prospective, controlled case series study during an outbreak of WNV infection between August 15 and October 24, 2003, of 64 consecutive patients who presented with clinical manifestations consistent with WNV disease. In each patient, standardized clinical and biologic data were collected. An ophthalmologic examination searching particularly for multifocal chorioretinitis was performed. RESULTS: Of 64 patients who presented primarily with meningitis and/or encephalitis, 36 had IgM antibodies against WNV. The WNV-infected patients tended to be older (median age of 54 years vs 46 years in WNV infection and control groups, respectively) and more frequently had diabetes (30% vs 7% in WNV infection and control groups, respectively; P = .03). Multifocal chorioretinitis was found in 75% of WNV-infected patients but in no patient in the control group (P = .001). Blood glucose and amylase levels were higher in WNV-infected patients, whereas serum sodium levels were lower. The cerebrospinal fluid leukocyte count and protein levels were significantly higher in WNV meningitis or encephalitis. Overall, multifocal chorioretinitis had 100% specificity and 73% sensitivity (88% when only patients with meningitis or encephalitis were analyzed) for the diagnosis of WNV. Multivariate analysis disclosed multifocal chorioretinitis as the only predictor of WNV infection (odds ratio, 62; 95% confidence interval, 6-700; P = .001). CONCLUSION: Multifocal chorioretinitis appears to be a specific marker of WNV infection, particularly in patients who present with meningoencephalitis. An ophthalmologic examination should be part of the routine evaluation of such patients.
Descriptors: chorioretinitis, disease outbreaks, eye infections, West Nile fever, antibodies, viral immunology, enzyme linked immunosorbent assay, prospective studies, severity of illness index, Tunisia, West Nile virus.

Abroug, F., L. Ouanes Besbes, I. Ouanes, N. Nciri, F. Dachraoui, and F. Najjar (2006). Adrenal insufficiency in severe West Nile Virus infection. Intensive Care Medicine 32(10): 1636-1639.
Abstract: OBJECTIVE: To explore adrenal function in severe West Nile virus (WNV) infection. DESIGN AND SETTING: Prospective interventional cohort study in a medical ICU of a teaching hospital. PATIENTS: Ten consecutive patients (seven men, mean age 64[Symbol: see text]+/-[Symbol: see text]12[Symbol: see text]years, mean SAPS II 26[Symbol: see text]+/-[Symbol: see text]6) with definite diagnosis of WNV related meningoencephalitis and variable proportion of organ/system failure. All patients had fever (mean body temperature 39[Symbol: see text]+/-[Symbol: see text]1 degrees C) and altered mental status (mean Glasgow Coma Score 11[Symbol: see text]+/-[Symbol: see text]2). Mean SOFA score was 9[Symbol: see text]+/-[Symbol: see text]2; eight patients had systemic inflammatory response syndrome, five septic shock, and six acute respiratory failure (usually from central origin) requiring mechanical ventilation. INTERVENTIONS: A short corticotropin test was performed in each patient to assess the adrenal function. MEASUREMENTS AND RESULTS: Cortisol response was defined as the difference between baseline and corticotropin-stimulated peak. Absolute adrenal insufficiency was defined by a baseline cortisol level below 15[Symbol: see text]mug/dl (415[Symbol: see text]nmol/l). Relative insufficiency was defined by a cortisol response of 9[Symbol: see text]mug/dl (250[Symbol: see text]nmol/l) or less. Relative adrenal insufficiency, defined by a corticotropin response below 9[Symbol: see text]mug/dl, was observed in seven while the remaining three had normal cortisol response; six out of these seven died in the ICU. All patients with normal adrenal function survived. CONCLUSION: Adrenal insufficiency is frequent in severe WNV infection and carries a poor outcome. In the absence of specific effective treatment, our data provide a rational to investigate a supplemental corticosteroid treatment in a controlled trial.
Descriptors: West Nile virus, adrenal function, meningoencephalitis, corticotropin test, adrenal insufficiency, prognosis.

Alexander, J.J., A.S. Lasky, and W.D. Graf (2006). Stroke associated with central nervous system vasculitis after West Nile virus infection. Journal of Child Neurology 21(7): 623-625.
Abstract: We report the association of West Nile virus infection, isolated vasculitis, and stroke in a 9-year-old girl. West Nile virus is of growing epidemiologic importance and should be considered in the differential diagnosis of stroke etiologies, especially during late summer and in patients with a history of exposure in areas where West Nile virus transmission is present.
Descriptors: cerebrovascular accident, vasculitis, central nervous system, West Nile fever complications, child.

Ali, M., Y. Safriel, J. Sohi, A. Llave, and S. Weathers (2005). West Nile virus infection: MR imaging findings in the nervous system. AJNR. American Journal of Neuroradiology 26(2): 289-297.
Abstract: BACKGROUND AND PURPOSE: West Nile virus (WNV) infection is an ongoing seasonal epidemic. We correlated the MR imaging findings with the clinical presentations and outcomes of WNV infection. METHODS: We reviewed 14 brain and three spinal MR images: nonenhanced and contrast-enhanced T1-weighted images (T1WIs) and T2-weighted images (T2WIs), nonenhanced fluid-attenuated inversion recovery (FLAIR) images (11 patients) and enhanced FLAIR images (three patients), with diffusion-weighted (DW) images and apparent diffusion coefficient maps. WNV infection was diagnosed by means of enzyme-linked immunosorbent assay with a plaque reduction neutralization test. We also correlated the MR findings with the clinical presentation, course, and outcome to determine their prognostic importance. RESULTS: MR imaging findings included: 1) normal (five patients); 2) DW imaging-only abnormalities in the white matter, corona radiata, and internal capsule (four patients); 3) hyperintensity on FLAIR images and T2WIs in the lobar gray and white matter, cerebellum, basal ganglia, thalamus and internal capsule, pons and midbrain (three patients); 4) meningeal involvement (two patients); and 5) spinal cord, cauda equina, and nerve root involvement (three patients). All patients with finding 1 and all but one with finding 2 recovered completely. Two patients with finding 3 died. Those with finding 4 or 5 had residual neurologic deficits that were severe or moderate to severe, respectively. CONCLUSION: Patients with normal MR images or abnormalities on only DW images had the best prognosis, while those with abnormal signal intensity on T2WI and FLAIR images had the worst outcomes. No definite predilection for any specific area of the brain parenchyma was noted.
Descriptors: central nervous system, viral diseases pathology, magnetic resonance imaging, West Nile fever diagnosis, adolescent, adult, aged, middle aged.

Anon (2006). West nile virus a looming deadly threat for liver transplantation. Transplantation 82(1 Suppl 2): 150.
Descriptors: West Nile virus, liver transplantation, deadly threat, infection, abstract.

Anon (2005). West Nile virus infections in organ transplant recipients--New York and Pennsylvania, August-September, 2005. Morbidity and Mortality Weekly Report 54(40): 1021-3.
Abstract: In September 2005, West Nile virus (WNV) infection was confirmed in three of four recipients of organs transplanted from a common donor. Two recipients subsequently had neuroinvasive disease, one recipient had asymptomatic WNV infection, and a fourth recipient apparently was not infected. This report summarizes the ongoing investigation. Clinicians should be aware of the potential for transplant-associated transmission of infectious disease.
Descriptors: organ transplantation, West Nile fever transmission, West Nile virus, New York, Pennsylvania.

Arnold, J.C., G.A. Revivo, M.O. Senac, and J.A. Leake (2005). West Nile virus encephalitis with thalamic involvement in an immunocompromised child. Pediatric Infectious Disease Journal 24(10): 932-934.
Abstract: West Nile virus has been an increasingly important pathogen in the United States since it was first reported in 1999. Neuroinvasive West Nile virus has been infrequently reported in the pediatric population. We report a case of severe West Nile virus encephalitis with cranial magnetic resonance imaging findings not yet described in children.
Descriptors: immunocompromised host, thalamus, West Nile fever, humans.

Barshes, N.R., E.E. Agee, T. Zgabay, F.C. Brunicardi, J.A. Goss, and M.E. Debakey (2006). West nile virus encephalopathy following pancreatic islet transplantation. American Journal of Transplantation 6(12): 3037.
Descriptors: West Nile virus, encephalopathy, pancreatic islet transplantation, infection, transplants, surgery.

Batalis, N.I., L. Galup, S.R. Zaki, and J.A. Prahlow (2005). West Nile virus encephalitis. American Journal of Forensic Medicine and Pathology 26(2): 192-196.
Abstract: West Nile virus (WNV) is a mosquito-borne virus that has caused a large number of deaths in the United States since the first outbreak in New York City in 1998. The outbreak initially was limited to the northeast but has since spread across the entire continental United States. WNV causes a variety of clinical symptoms, but the most severe consequences result from central nervous system infection, resulting in meningitis, encephalitis, or meningoencephalitis. We present a case of a 62-year-old male with metastatic cancer, who died as a result of WNV encephalitis. This is followed by a discussion on the epidemiology of WNV and a detailed summary of the methods and resources available to make a diagnosis of WNV infection postmortem. The material presented in the discussion should provide the forensic pathologist with all the information necessary to make a diagnosis of WNV infection postmortem. If nothing else, the routine collection and storage of serum, cerebrospinal fluid, and tissue for every case can enable the forensic pathologist to make this diagnosis even in cases in which WNV is not suspected until after autopsy.
Descriptors: mosquito vectors, West Nile fever, brain pathology, carcinoma, small cell therapy, chills, confusion, fever, forensic pathology, lung neoplasms, psychomotor agitation.

Batsis, J.A. and M.P. Phy (2005). West Nile virus meningitis in a chronic immunosuppressed patient with rheumatoid arthritis. Clinical Rheumatology 24(5): 548-550.
Abstract: The clinical presentation of West Nile virus (WNV) can be severe in immunosuppressed patients. A 65-year-old with steroid-dependent rheumatoid arthritis on infliximab and methotrexate presented with meningitis and profound muscular weakness. Serum WNV IgM and IgG antibody were positive. WNV should be included in the differential diagnosis of neurological symptoms in peak months.
Descriptors: rheumatoid arthritis, immunocompromised host, meningitis, West Nile fever, monoclonal antibodies, antirheumatic agents, immunosuppressive agents, West Nile virus.

Bhangoo, S., R. Chua, C. Hammond, Z. Kimmel, I. Semenov, A. Videnovic, J. Kessler, and M. Borsody (2005). Focal neurological injury caused by West Nile virus infection may occur independent of patient age and premorbid health. Journal of the Neurological Sciences 234(1-2): 93-98.
Abstract: INTRODUCTION: Limited evidence suggests that focal neurological injury (e.g., acute flaccid paralysis) caused by infection with the West Nile virus (WNV) is more common in older patients. We re-evaluate this association in a series of patients who were infected with the WNV during the 2002 epidemic. METHODS: We performed a retrospective chart review of 34 patients who were hospitalized for treatment of serologically confirmed WNV infection. Measurements included the patient's demographic characteristics, baseline medical diagnoses, the occurrence of symptoms and exam findings, the results of various diagnostic tests, and the patient's clinical outcome. RESULTS: Patients infected with the WNV who developed focal neurological injury were found to be comparable to patients who did not develop focal neurological injury both in terms of patient age and the number of medical conditions the patient had prior to infection. This is in contrast to WNV-infected patients who developed an encephalitis-like clinical course, or who died or were institutionalized after their hospitalization; such patients tended to be older and-in cases with a poor outcome-have more medical conditions prior to WNV infection. CONCLUSIONS: In our patient group, focal neurological injury caused by WNV infection was not related to advanced patient age or to the number of medical conditions the patient had prior to infection. Our findings bring into question commonly held views about the development of focal neurological injury caused by WNV infection, and they raise concerns about the management of future WNV epidemics and the testing and use of potential antiviral treatments against this infection.
Descriptors: health status, nervous system diseases, West Nile fever, cerebrospinal fluid, West Nile virus (WNV).

Bode, A.V., J.J. Sejvar, W.J. Pape, G.L. Campbell, and A.A. Marfin (2006). West Nile virus disease: A descriptive study of 228 patients hospitalized in a 4-county region of Colorado in 2003. Clinical Infectious Diseases an Official Publication of the Infectious Diseases Society of America 42(9): 1234-1240.
Abstract: BACKGROUND: Risk factors for complications of West Nile virus disease and prognosis in hospitalized patients are incompletely understood. METHODS: Demographic characteristics and data regarding potential risk factors, hospitalization, and dispositions were abstracted from medical records for residents of 4 Colorado counties who were hospitalized in 2003 with West Nile virus disease. Univariate and multivariate analyses were used to identify factors associated with West Nile encephalitis (WNE), limb weakness, or death by comparing factors among persons with the outcome of interest with factors among those without the outcome of interest. RESULTS: Medical records of 221 patients were reviewed; 103 had West Nile meningitis, 65 had WNE, and 53 had West Nile fever. Respiratory failure, limb weakness, and cardiac arrhythmia occurred in all groups, with significantly more cases of each in the WNE group. Age, alcohol abuse, and diabetes were associated with WNE. Age and WNE were associated with limb weakness. The mortality rate in the WNE group was 18%; age, immunosuppression, requirement of mechanical ventilation, and history of stroke were associated with death. Only 21% of patients with WNE who survived returned to a prehospitalization level of function. The estimated incidence of West Nile fever cases that required hospitalization was 6.0 cases per 100,000 persons; West Nile fever was associated with arrhythmia, limb weakness, and respiratory failure. CONCLUSIONS: Persons with diabetes and a reported history of alcohol abuse and older persons appear to be at increased risk of developing WNE. Patients with WNE who have a history of stroke, who require mechanical ventilation, or who are immunosuppressed appear to be more likely to die. Respiratory failure, limb weakness, and arrhythmia occurred in all 3 categories, but there were significantly more cases of all in the WNE group.
Descriptors: West Nile fever, retrospective studies, risk factors, Colorado, humans.
Notes: Comment In: Clin Infect Dis. 2006 Aug 1;43(3):388-9.

Bragin Sanchez, D. and P.P. Chang (2005). West Nile virus encephalitis infection in a heart transplant recipient: A case report. Journal of Heart and Lung Transplantation the Official Publication of the International Society for Heart Transplantation 24(5): 621-623.
Abstract: Infection with West Nile virus (WNV) ranges from causing no symptoms to causing non-specific fever, meningitis, meningo-encephalitis and death. Advanced age and immunosuppression are the greatest risk factors for the development of encephalitis or other neurologic manifestations of WNV. We report the first fatal case of primary WNV infection in an orthotopic heart transplant recipient. We reviewed the literature on WNV infection in the general population and in immunocompromised hosts. As WNV becomes more common in the United States, it will become an increasing threat to our transplant population.
Descriptors: heart transplantation, immunocompromised host, immunosuppressive agents, West Nile fever immunology, fatal outcome, humans, North Carolina.

Brenner, W., G. Storch, R. Buller, R. Vij, S. Devine, and J. Dipersio (2005). West nile virus encephalopathy in an allogeneic stem cell transplant recipient: Use of quantitative PCR for diagnosis and assessment of viral clearance. Bone Marrow Transplantation 36(4): 369-370. ISSN: 0268-3369.
Descriptors: encephalopathy, quadriplegia, chronic myeloid leukemia, neoplastic disease, heart disease, magnetic resonance imaging, diagnostic techniques, stem cell transplantation, quantitative polymerase chain reaction, viral clearance.

Briese, T. and K.A. Bernard (2005). West Nile virus--An old virus learning new tricks? Journal of Neurovirology 11(5): 469-475.
Abstract: West Nile virus (WNV) has spread across the United States causing annual outbreaks since its emergence in 1999. Although severe disease develops only in about 1% of infections, WNV has claimed a total of 564 lives in the 5 years from 1999 to 2003. Observation of flaccid paralysis due to WNV infection at a higher incidence than previously documented and the devastating mortality recorded in infected American bird species triggered concerns about a potentially enhanced virulence of this virus. Here we summarize recent observations made during the American outbreaks regarding host range and transmission modes of WNV, and discuss epidemiological aspects of the emergence of this pathogen in the new habitat.
Descriptors: disease outbreaks, West Nile fever, West Nile virus, transmission of animal diseases, arthropod vectors, birds, disease reservoirs, mortality, pregnancy complications, United States.

Busch, M.P., D.J. Wright, B. Custer, L.H. Tobler, S.L. Stramer, S.H. Kleinman, H.E. Prince, C. Bianco, G. Foster, L.R. Petersen, G. Nemo, and S.A. Glynn (2006). West Nile virus infections projected from blood donor screening data, United States, 2003. Emerging Infectious Diseases 12(3): 395-402.
Abstract: National blood donor screening for West Nile virus (WNV) RNA using minipool nucleic acid amplification testing (MP-NAT) was implemented in the United States in July 2003. We compiled national NAT yield data and performed WNV immunoglobulin M (IgM) testing in 1 WNV-epidemic region (North Dakota). State-specific MP-NAT yield, antibody seroprevalence, and the average time RNA is detectable by MP-NAT were used to estimate incident infections in 2003. WNV donor screening yielded 944 confirmed viremic donors. MP-NAT yield peaked in August with >0.5% of donations positive for WNV RNA in 4 states. Peak IgM seroprevalence for North Dakota was 5.2% in late September. The average time viremia is detectable by MP-NAT was 6.9 days (95% confidence interval [CI] 3.0-10.7). An estimated 735,000 (95% CI 322,000-1,147,000) infections occurred in 2003, with 256 (95% CI 112-401) infections per neuroinvasive case. In addition to preventing transfusion-transmitted WNV infection, donor screening can serve as a tool to monitor seasonal incidence in the general population.
Descriptors: blood donors, West Nile fever, RNA, viral blood, seasons, sensitivity and specificity, time factors, United State, West Nile virus.

Cairoli, O. (2005). The West Nile Virus and the dialysis/transplant patient. Nephrology News and Issues 19(12): 73-75.
Descriptors: disease outbreaks, kidney transplantation, renal dialysis, West Nile fever, cross infection, immunocompromised host, United States.

Cannon, A.B., J.A. Luff, A.C. Brault, N.J. MacLachlan, J.B. Case, E.N. Green, and J.E. Sykes (2006). Acute encephalitis, polyarthritis, and myocarditis associated with West Nile virus infection in a dog. Journal of Veterinary Internal Medicine 20(5): 1219-1223.
Descriptors: arthritis, dog diseases, myocarditis, West Nile fever, West Nile virus, fatal outcome, myocarditis, drug therapy, encephalitis.

Cao, N.J., C. Ranganathan, W.J. Kupsky, and J. Li (2005). Recovery and prognosticators of paralysis in West Nile virus infection. Journal of the Neurological Sciences 236(1-2): 73-80.
Abstract: Previous studies have demonstrated that lesions of the anterior horn motor neurons are the primary pathology in patients with paralysis due to West Nile virus (WNV) infection. To characterize recovery and identify prognostic factors for the recovery of paralysis, we investigated 11 patients with electrophysiology testing and muscle biopsy, and one with autopsy. We found that limb weakness was markedly asymmetric and differed between upper and lower extremities, suggesting focal or segmental involvement of the spinal cord anterior horn. This was supported by segmental depletion of spinal motor neurons at autopsy. Clinical recovery was variable during a 21-month follow-up period. To explain variability, we performed motor unit number estimation (MUNE) in six patients. MUNE values and strength were correlated in tested muscles. We also detected motor nerve terminal damages in muscle biopsies, suggesting another possible mechanism for transient weakness and variable recovery. We conclude that the type of pathological lesions may vary in paralytic WNV infection, and different degrees or combinations of motor neuron loss and motor nerve terminal changes may account for the observed degrees of weakness and recovery.
Descriptors: paralysis etiology, West Nile fever complications, adult, aged, aged, 80 and over, antigens, cd metabolism, electromyography methods, extremities physiopathology, immunohistochemistry methods, laterality, microscopy, electron methods, middle aged, motor neurons physiology, muscle weakness etiology, muscle weakness metabolism, muscle weakness pathology, muscle, skeletal metabolism, skeletal pathology, skeletal ultrastructure, neural conduction, paralysis pathology, prognosis, West Nile fever pathology.

Carson, P.J., P. Konweko, K.S. Wold, P. Mariani, S. Goli, P. Bergloff, and R.D. Crosby (2006). Long-term clinical and neuropsychological outcomes of West Nile virus infection. Clinical Infectious Diseases an Official Publication of the Infectious Diseases Society of America 43(6): 723-30.
Abstract: BACKGROUND: Since its introduction in 1999, West Nile virus has rapidly become the most common arboviral infection in North America. Little is known about the long-term clinical sequelae of West Nile virus infection. METHODS: A total of 49 patients with laboratory-confirmed West Nile virus infection were identified through state-based surveillance. Stratification for disease severity was based on hospitalization during the infection episode. Assessment occurred a mean of 13 months after diagnosis. Medical records were reviewed, and a complete neurologic examination was performed. Standardized surveys for quality of life, functional ability, fatigue, and depression were performed for all subjects. An extensive battery of neuropsychological tests was performed to assess cognitive function. RESULTS: Self-reported fatigue, memory problems, extremity weakness, word-finding difficulty, and headache were common complaints. Standardized survey data confirmed an overall sense of poor physical health, fatigue, depression, and moderate-to-severe disability in 24 (49%), 24 (49%), 12 (24%), and 4 (8%) patients, respectively. New tremor was seen or reported for 10 (20%) of the patients. Neuropsychological testing showed abnormalities of motor skills, attention, and executive functions. Univariate analysis of multiple risk factors did not identify any predictors of adverse outcomes. CONCLUSIONS: Multiple somatic complaints, tremor, and abnormalities in motor skills and executive functions are common long-term problems among patients who have had West Nile virus infection. Patients with milder illness are just as likely as patients with more-severe illness to experience adverse outcomes.
Descriptors: West Nile fever diagnosis, aged, depression, fatigue, follow up studies, memory disorders, middle aged, motor skills disorders, muscle weakness, neuropsychological tests, population surveillance, risk assessment, tremor diagnosis, West Nile fever drug therapy, West Nile fever epidemiology.

Chan, C.K., S.A. Limstrom, D.G. Tarasewicz, and S.G. Lin (2006). Ocular features of west nile virus infection in North America: a study of 14 eyes. Ophthalmology 113(9): 1539-46.
Abstract: PURPOSE: To present a case series of ocular findings of West Nile virus infection (WNVI) in North America. DESIGN: Retrospective, noncomparative, observational case series. PARTICIPANTS: All patients were referred to the authors for WNVI with ocular involvement between the years 2002 and 2005. METHODS: Chart review was performed on all participants. All participants underwent complete ophthalmic evaluation during each examination, including best-corrected Snellen visual acuity measurement, tonometry, slit-lamp biomicroscopy of the anterior and posterior segments, and dilated fundus examination with indirect ophthalmoscopy. Fundus photography and fluorescein angiography were also performed on all eyes. Relevant ocular findings associated with WNVI were recorded and tabulated. MAIN OUTCOME MEASURES: The authors studied the characteristics, frequency, and locations of ocular lesions found in participants' eyes. RESULTS: There were 14 eyes (7 patients) with ocular West Nile virus lesions from 2002 to 2005. Average patient age was 58.4 years (range, 32-85 years). Ocular findings in descending order of frequency included multifocal chorioretinal target lesions in 12 eyes (85.7%), retinal hemorrhages in 7 eyes (50.0%), vitritis in 6 eyes (42.9%), chorioretinal linear streaks in 4 eyes (28.6%), perivascular sheathing and vasculitis in 4 eyes (28.6%), narrowed retinal vessels in 4 eyes (28.6%), disc edema in 4 eyes (28.6%), optic atrophy in 2 eyes (14.3%), vascular occlusion in 2 eyes (14.3%), and VIth nerve palsy in 1 eye (7.1%). Peripheral fundus lesions were found in all 14 eyes (100%), whereas posterior fundus lesions were found in 8 eyes (57.1%). Five patients (71.4%) were diabetic. Diabetic retinopathy was present in 7 eyes (70%). CONCLUSIONS: Multifocal choroiditis is the most common ocular manifestation associated with WNVI, with a typically benign clinical course. Less frequent ocular lesions, including optic neuritis and occlusive vasculitis, frequently induce persistent and likely permanent visual deficit. Diabetic patients and those older than 50 years of age are more vulnerable to the more severe features of WNVI, including more serious ocular lesions.
Descriptors: eye infections, viral diagnosis, West Nile fever diagnosis, West Nile virus, adult, aged, 80 and over, chorioretinitis, fluorescein angiography, middle aged, ophthalmoscopy, retrospective studies, tonometry, ocular, vision disorders, visual acuity.

Chan Tack, K.M. and G. Forrest (2006). West nile virus meningoencephalitis and acute flaccid paralysis after infliximab treatment. Journal of Rheumatology 33(1): 191-2.
Abstract: West Nile virus (WNV) can cause severe central nervous system (CNS) illnesses including meningoencephalitis (MNE) and acute flaccid paralysis (AFP). Risk factors include advanced age, immunosuppression, cancer, and diabetes. In vitro studies show that tumor necrosis factor (TNF) has anti-WNV activity and is protective against WNV infection. Anti-TNF-a monoclonal antibodies may increase susceptibility to WNV by inhibiting an adequate TNF-a response, leading to prolonged viremia, viral penetration into the CNS, and fulminant WNV-CNS disease. We describe a fatal case of WNV with MNE and AFP after infliximab therapy. During WNV outbreaks, clinicians should encourage patients receiving anti-TNF-a drugs to take appropriate preventive measures because of the risk of severe WNV-CNS disease.
Descriptors: antibodies, monoclonal adverse effects, immunocompromised host, immunosuppressive agents adverse effects, paraplegia diagnosis, West Nile fever diagnosis, aged, viral cerebrospinal fluid, fatal outcome, paraplegia etiology, West Nile fever complications, West Nile virus, West Nile virus isolation and purification.

Chan Tack, K.M. and G. Forrest (2005). Failure of interferon alpha-2b in a patient with West Nile virus meningoencephalitis and acute flaccid paralysis. Scandinavian Journal of Infectious Diseases 37(11-12): 944-6.
Abstract: WNV infection can cause meningoencephalitis (MNE) and acute flaccid paralysis (AFP). Both syndromes are associated with high morbidity and mortality. Interferon alpha-2b (IFN-alpha-2b) inhibits WNV replication in vitro. To date, 5 patients with WNV-CNS disease have recovered neurologic function with IFN-alpha-2b. We report the first failure of IFN-alpha-2b in the treatment of WNV-MNE-AFP.
Descriptors: interferon alfa 2b therapeutic use, paraplegia drug therapy, West Nile fever drug therapy, acute disease, aged, antiviral agents therapeutic use, fatal outcome, paraplegia etiology, treatment failure, West Nile fever complications.

Cinatl, J.J., M. Michaelis, C. Fleckenstein, G. Bauer, H. Kabickova, M. Scholz, H.F. Rabenau, and H.W. Doerr (2006). West Nile virus infection induces interferon signalling in human retinal pigment epithelial cells. Investigative Ophthalmology and Visual Science 47(2): 645-51.
Abstract: PURPOSE: In addition to neuroinvasive disease, West Nile virus (WNV) infection is frequently associated with self-limiting chorioretinitis and vitritis. However, the mechanisms of ophthalmic WNV infection are rarely investigated, in part because of the lack of reliable in vitro models. The authors therefore established the first model of ocular WNV infection and investigated interaction of WNV with IFN signal-transduction mechanisms. METHODS: Human retinal pigment epithelial (RPE) cells were infected with WNV strain NY385-99 at a multiplicity of infection of 5. Virus replication was evaluated by virus titers at different times after infection. The susceptibility of RPE cells to WNV infection was confirmed by transmission electron microscopy. IFN-beta expression was assessed by quantitative real-time PCR and by measurements of antiviral activity in cell culture supernatants. IFN signaling was evaluated by phosphorylation of transducer and activator of transcription 1 and 2 (STAT1/2) proteins, with immunoblot analysis. RESULTS: RPE cells appeared to be highly sensitive to WNV infection. Maximum viral titers were found 24 hours after infection, followed by a continuous decline during the course of infection. WNV infection of RPE cells was followed by increased IFN-beta expression associated with IFN signaling and subsequent inhibition of WNV replication. CONCLUSIONS: In this study, the first cell culture model of ophthalmic WNV infection was developed and characterized in RPE cells, and the molecular mechanisms of WNV infection were studied. The data suggest that WNV induces a general antiviral state in RPE cells. This general antiviral state correlates with WNV-induced IFN signaling in retinal cells.
Descriptors: interferon beta biosynthesis, pigment epithelium of eye virology, signal transduction physiology, West Nile virus, blotting, western, cell culture techniques, Cercopithecus aethiops, interferon beta genetics, microscopy, electron, transmission, models, biological, phosphorylation, pigment epithelium of eye metabolism, pigment epithelium of eye ultrastructure, reverse transcriptase polymerase chain reaction, stat1 transcription factor metabolism, stat2 transcription factor metabolism, vero cells, virus replication physiology, West Nile virus ultrastructure.

Civen, R., F. Villacorte, D.T. Robles, D.E. Dassey, C. Croker, L. Borenstein, S.M. Harvey, and L. Mascola (2006). West Nile virus infection in the pediatric population. Pediatric Infectious Disease Journal 25(1): 75-8.
Abstract: In 2004, Los Angeles County confirmed 11 cases of symptomatic West Nile virus (WNV) infections in children younger than 18 years of age. Eight had WNV fever, 2 had meningitis and 1 had encephalitis. Fever, rash, nausea and vomiting were the most prominent symptoms at presentation; median duration of illness was 7 days. Clinicians should be aware of the risk of WNV illness, confirm this diagnosis and report suspected WNV cases to their local health department.
Descriptors: West Nile fever epidemiology, adolescent, California epidemiology, child, preschool, encephalitis, viral epidemiology, exanthema, fever, meningitis, viral epidemiology, nausea, time factors, vomiting, West Nile fever physiopathology.

Cunha, B.A. (2006). West Nile virus encephalitis: clinical diagnostic and prognostic indicators in compromised hosts. Clinical Infectious Diseases an Official Publication of the Infectious Diseases Society of America 43(1): 117.
Descriptors: immunocompromised host, West Nile fever diagnosis, lymphoma, b cell complications, b cell immunology, prognosis, serologic tests, West Nile fever immunology.
Notes: Comment On: Clin Infect Dis. 2006 Mar 1;42(5):680-3.

Davis, L.E., R. DeBiasi, D.E. Goade, K.Y. Haaland, J.A. Harrington, J.B. Harnar, S.A. Pergam, M.K. King, B.K. DeMasters, and K.L. Tyler (2006). West Nile virus neuroinvasive disease. Annals of Neurology 60(3): 286-300.
Abstract: Since 1999, there have been nearly 20,000 cases of confirmed symptomatic West Nile virus (WNV) infection in the United States, and it is likely that more than 1 million people have been infected by the virus. WNV is now the most common cause of epidemic viral encephalitis in the United States, and it will likely remain an important cause of neurological disease for the foreseeable future. Clinical syndromes produced by WNV infection include asymptomatic infection, West Nile Fever, and West Nile neuroinvasive disease (WNND). WNND includes syndromes of meningitis, encephalitis, and acute flaccid paralysis/poliomyelitis. The clinical, laboratory, and diagnostic features of these syndromes are reviewed here. Many patients with WNND have normal neuroimaging studies, but abnormalities may be present in areas including the basal ganglia, thalamus, cerebellum, and brainstem. Cerebrospinal fluid invariably shows a pleocytosis, with a predominance of neutrophils in up to half the patients. Diagnosis of WNND depends predominantly on demonstration of WNV-specific IgM antibodies in cerebrospinal fluid. Recent studies suggest that some WNV-infected patients have persistent WNV IgM serum and/or cerebrospinal fluid antibody responses, and this may require revision of current serodiagnostic criteria. Although there is no proven therapy for WNND, several vaccines and antiviral therapy with antibodies, antisense oligonucleotides, and interferon preparations are currently undergoing human clinical trials. Recovery from neurological sequelae of WNV infection including cognitive deficits and weakness may be prolonged and incomplete.
Descriptors: nervous system diseases, West Nile fever , West Nile virus.

Del Giudice, P., I. Schuffenecker, H. Zeller, M. Grelier, F. Vandenbos, P. Dellamonica, and E. Counillon (2005). Skin manifestations of West Nile virus infection. Dermatology 211(4): 348-350.
Abstract: West Nile virus (WNV) infection is a potentially lethal arbovirus infection. Many notable outbreaks have occurred during the last few years throughout the world, including Europe and the USA. The severity of the disease is mainly related to the neurological complications. A maculopapular exanthema is reported as a clinical sign of the disease. Recently an outbreak of WNV infection occurred in southern France. Three patients out of 6 had a similar skin roseola-like eruption. The cluster of 3 cases of similar febrile roseola of unexplained cause during the same week led to the diagnosis of the first WNV human outbreak in France for 40 years. Copyright 2005 S. Karger AG, Basel.
Descriptors: exanthema virology, skin diseases, viral diagnosis, West Nile fever diagnosis, adult, differential diagnosis, serologic tests.

Del Giudice, P., I. Schuffenecker, H. Zeller, M. Grelier, F. Vandenbos, P. Dellamonica, and E. Counillon (2005). Skin manifestations of West Nile virus infection. Dermatology 211(4): 348-350. ISSN: 1018-8665.
Online: Skin Manifestations of West Nile Virus Infection
Descriptors: West Nile virus, erythema, skin manifestations, maculopapular exanthema, roseola, neurological complications.

Ding, X., X. Wu, T. Duan, M. Siirin, H. Guzman, Z. Yang, R.B. Tesh, and S.Y. Xiao (2005). Nucleotide and amino acid changes in West Nile virus strains exhibiting renal tropism in hamsters. American Journal of Tropical Medicine and Hygiene 73(4): 803-807.
Abstract: Recent studies have shown that West Nile virus (WNV) can induce an asymptomatic persistent infection in the kidneys of experimentally infected hamsters. The chronically infected rodents shed virus in their urine for up to 8 months, despite the disappearance of viremia and the development of high levels of neutralizing antibodies. WNV, like most members of the Japanese encephalitis virus complex (Flavivirus; Flaviviridae), is assumed to be mainly neurotropic; little is known about the genetic basis for its renal tropism. In this study, complete sequence analyses were done to compare four WNV isolates from the urines of persistently infected hamsters with the wild-type parent virus (NY 385-99). Nucleotide changes, ranging from 0.05% to 0.09%, were identified in all of the WNV isolates from urine; most of the changes were in coding regions, causing amino acid substitutions in the E, NS1, NS2B, and NS5 proteins. The genetic changes associated with renal tropism were also accompanied by a loss of virulence for hamsters and a change in plaque morphology.
Descriptors: amino acid substitution, kidney, West Nile fever, West Nile virus, chronic disease, animal disease models, kidney pathology, molecular sequence data, urine virology, virulence.

Ferguson, D.D., K. Gershman, A. LeBailly, and L.R. Petersen (2005). Characteristics of the rash associated with West Nile virus fever. Clinical Infectious Diseases 41(8): 1204-1207.
Abstract: We characterized rash in 15 patients with West Nile virus (WNV) fever. Generalized, maculopapular rash typically occurred on days 5-12 of illness. Dysesthesia was reported by 27% of patients, and pruritus by 33% of patients. Because the rash was nonspecific and serologic test results were often negative for WNV at presentation, convalescent-phase testing was frequently required to diagnose WNV fever.
Descriptors: dermatitis diagnosis, West Nile virus fever, maculopapular rash, symptoms.

Fonseca, K., G.D. Prince, J. Bratvold, J.D. Fox, M. Pybus, J.K. Preksaitis, and P. Tilley (2005). West Nile virus infection and conjunctival exposure. Emerging Infectious Diseases 11(10): 1648-1649. ISSN: 1080-6040.
Descriptors: bird diseases, conjunctiva, crows, occupational exposure, West Nile fever transmission, West Nile virus isolation and purification.

Francisco, A.M., C. Glaser, E. Frykman, B. Cole, M. Cheung, H. Meyers, M. Ginsberg, A. Deckert, C. Jean, and B.A. Jinadu (2006). 2004 California pediatric West Nile virus case series. Pediatric Infectious Disease Journal 25(1): 81-84.
Abstract: Relatively few pediatric West Nile virus cases have been recognized in the United States since the virus was first identified in 1999. We reviewed the clinical characteristics of 23 cases in pediatric patients that occurred in California in 2004 to better understand the infection in this population.
Descriptors: West Nile fever physiopathology, children California, viral encephalitis physiopathology, immunocompromised host, viral meningitis physiopathology, muscle hypotonia, paralysis, West Nile virus isolation and purification.

Frih Ayed, M., A. Boughammoura Bouatay, F. Ben Romdhane, S. Chebel, M. Chakroun, and N. Bouzouia (2005). Acute flaccid paralysis of the upper limbs associated with West Nile virus infection. European Neurology 54(3): 159-160.
Descriptors: muscle hypotonia, paralysis, West Nile fever complications, adult, electrodiagnosis, electromyography, neural conduction physiology, neurologic examination.

Gallian, P., X. De Lamballerie, P. De Micco, and G. Andreu (2005). Le virus West Nile: Generalites et implications en transfusion sanguine. [West Nile virus (WNV): Generalities and implications for blood transfusion]. Transfusion 12(1): 11-17.
Abstract: West Nile virus (WNV) is an arbovirus (genus Flavivirus, Family Flaviviridae, transmitted to humans by mosquito bite. In most cases (80%), human infection remains asymptomatic. Severe central nervous system complications (encephalitis and meningoencephalitis) are rare. In the Old World, the virus circulation has been demonstrated in Asia, Australia, Africa, Middle East and Europe. Several outbreaks in humans have been described. Following its introduction into North America in 1999, WN virus has been responsible of a large number of human cases in USA and Canada. For the first time, viral transmission by blood products was clearly demonstrated in USA in 2002. In France, the presence of virus has been reported in the Southeastern departments since 1962. In 2003, the occurrence of humans cases at specific geographical foci urged the French National Blood Agency (etablissement francais du sang) to take preventive measures for evaluating the virus transmission risks.
Descriptors: West Nile virus, arbovirus, mosquito vectors, symptoms of infection in humans, viral transmission by blood products.
Language of Text: French; Summary in English.

Garg, S. and L.M. Jampol (2005). Systemic and intraocular manifestations of West Nile virus infection. Survey of Ophthalmology 50(1): 3-13.
Abstract: Since the introduction of West Nile virus in the Western Hemisphere in 1999, the incidence of human infection has increased dramatically. As this virus spreads westward across the United States, ophthalmologists should be aware of this presently uncommon but important condition. Systemic features of West Nile virus infection are well characterized; however, the ophthalmic presentations are not widely known. Intraocular involvement with West Nile virus infection was first described in February 2003, and a variety of ophthalmic manifestations have since been recognized. A complete survey of the systemic and intraocular manifestations of West Nile virus infection relevant to the ophthalmologist is presented.
Descriptors: chorioretinitis, eye infections, viral etiology, optic neuritis, uveitis, West Nile fever, West Nile virus isolation and purification, United States.

Garg, S., L.M. Jampol, J.F. Wilson, I.R. Batlle, and H. Buettner (2006). Ischemic and hemorrhagic retinal vasculitis associated with West Nile virus infection. Retina 26(3): 365-367.
Descriptors: eye infections, viral virology, ischemia virology, retinal hemorrhage virology, retinal vasculitis virology, retinal vessels pathology, West Nile fever, human, viral blood antibodies, viral cerebrospinal fluid, viral diagnosis, fluorescein angiography, immunoglobulin G blood, immunoglobulin M cerebrospinal fluid, West Nile virus.

Gorsche, R. and P. Tilley (2005). The rash of West Nile virus infection. Canadian Medical Association Journal 172(11): 1440.
Descriptors: exanthema, West Nile fever, West Nile virus, Alberta, rural population, time factors.

Green, M.S., M. Weinberger, J. Ben Ezer, H. Bin, E. Mendelson, D. Gandacu, Z. Kaufman, R. Dichtiar, A. Sobel, D. Cohen, and M.Y. Chowers (2005). Long-term Death Rates, West Nile virus epidemic, Israel, 2000. Emerging Infectious Diseases 11(11): 1754-1757. ISSN: 1080-6040.
Abstract: We studied the 2-year death rate of 246 adults discharged from hospital after experiencing acute West Nile Virus infection in Israel during 2000. The age- and sex-adjusted death rates were significantly higher than in the general population. This excess was greater for men. Significant adverse prognostic factors were age, male sex, diabetes mellitus, and dementia.
Descriptors: communicable diseases, emerging mortality, disease outbreaks, West Nile fever mortality, aged humans, Israel, risk factors, survival rate, West Nile virus.

Haaland, K.Y., J. Sadek, S. Pergam, L.A. Echevarria, L.E. Davis, D. Goade, J. Harnar, R.A. Nofchissey, C.M. Sewel, and P. Ettestad (2006). Mental status after West Nile virus infection. Emerging Infectious Diseases 12(8): 1260-1262. ISSN: 1080-6040 .
Abstract: Mental status after acute West Nile virus infection has not been examined objectively. We compared Telephone Interview for Cognitive Status scores of 116 patients with West Nile fever or West Nile neuroinvasive disease. Mental status was poorer and cognitive complaints more frequent with West Nile neuroinvasive disease (p = 0.005).
Descriptors: brain diseases, virology, mental status, West Nile fever complications, virus pathogenicity, acute disease, adult human.

Hayes, E.B. (2006). West Nile virus disease in children. Pediatric Infectious Disease Journal 25(11): 1065-1066.
Descriptors: West Nile fever diagnosis, vertical disease transmission, West Nile virus physiology.

Hayes, E.B., J.J. Sejvar, S.R. Zaki, R.S. Lanciotti, A.V. Bode, and G.L. Campbell (2005). Virology, pathology, and clinical manifestations of West Nile virus disease. Emerging Infectious Diseases 11(8): 1174-1179. ISSN: 1080-6040.
Abstract: West Nile virus (WNV) causes epidemics of febrile illness, meningitis, encephalitis, and flaccid paralysis. Since it was first detected in New York City in 1999, and through 2004, >16,000 WNV disease cases have been reported in the United States. Over the past 5 years, research on WNV disease has expanded rapidly. This review highlights new information regarding the virology, clinical manifestations, and pathology of WNV disease, which will provide a new platform for further research into diagnosis, treatment, and possible prevention of WNV through vaccination.
Descriptors: West Nile fever pathology, West Nile virus growth and development, antiviral agents, viral vaccines.

Hermanowska Szpakowicz, T., S. Grygorczuk, M. Kondrusik, J. Zajkowska, and S. Pancewicz (2006). Zakazenie Wirusem Zachodniego Nilu. [Infections caused by West Nile virus]. Przeglad Epidemiologiczny 60(1): 93-98.
Abstract: West Nile virus (WNV) is a flavivirus related to tick-borne encephalitis virus endemic in northeast of Poland. WNV circulates among wild birds, transmitted by wide range of haematophagous arthropods. Several mosquito species, especially Culex spp., can transmit WNV to humans. WNV is responsible for a broad range of clinical symptoms, from asymptomatic infection to severe encephalitis and polio-like myelitis. Elderly persons are at especially high risk of death and severe neurological complications, with mortality among patients over 65 years old with WNV-related encephalitis being as high as 35%. Warm and humid climate favors the spread of WNV, however, it can also be effectively transmitted in moderate climate zones. During the last decade a worldwide spread of WNV was observed, with establishment of new enzootic foci and growing number of human cases. WNV seems to be already present in several European countries, including Poland. We describe detection of anti-WNV IgM antibodies in serum of patient with acute febrile infection, which may constitute the first case of confirmed WNV infection in Poland.
Descriptors: viral antibodies, birds, climate, disease outbreaks, disease vectors, immunoglobulin M immunology, Poland, seasons, West Nile fever transmission, world health.
Language of Text: Polish.

Hochman, J.A. (2005). Misinterpretation of liver-function tests and West Nile virus infection in children. Pediatrics 115(5): 1445; Author Reply 1445-1446.
Descriptors: diagnostic errors, liver failure, acute diagnosis, transaminases blood, West Nile fever complications, child, ischemia complications, acute etiology, liver function tests.
Notes: Comment On: Pediatrics. 2004 Dec;114(6):1673-5.

Hoekstra, C. (2005). West Nile virus: a challenge for transplant programs. Progress in Transplantation 15(4): 397-400.
Abstract: West Nile virus is a new challenge for transplant programs worldwide. It is a mosquito-borne disease, which has become increasingly prevalent in North America since it was first recognized in New York in 1999. A review of a case study and the literature shows that the morbidity and mortality associated with West Nile virus infection and transplant recipients are alarmingly high. Treatment options are limited because of transplant programs' limited experience in working with this virus. Transplant programs must develop action plans for education on West Nile virus and its prevention to decrease the risk of infection among their transplant recipients.
Descriptors: infection control, organ transplantation adverse effects, West Nile fever prevention and control, immunocompromised host, lung transplantation, humans, North America, transplant recipients.

Huhn, G.D. and M.S. Dworkin (2006). Rash as a prognostic factor in West Nile virus disease. Clinical Infectious Diseases an Official Publication of the Infectious Diseases Society of America 43(3): 388-389.
Descriptors: exanthema etiology, West Nile fever complications, prognosis, rash, infections.
Notes: Comment On: Clin Infect Dis. 2006 May 1;42(9):1234-40.

Julander, J.G., Q.A. Winger, L.F. Rickords, P.Y. Shi, M. Tilgner, I. Binduga Gajewska, R.W. Sidwell, and J.D. Morrey (2006). West Nile virus infection of the placenta. Virology 347(1): 175-182. ISSN: 0042-6822.
Abstract: Intrauterine infection of fetuses with West Nile virus (WNV) has been implicated in cases of women infected during pregnancy. Infection of timed-pregnant mice on 5.5, 7.5, and 9.5 days post-coitus (dpc) resulted in fetal infection. Infection of dams on 11.5 and 14.5 dpc resulted in little and no fetal infection, respectively. Pre-implantation embryos in culture were also infected with WNV after the blastocyst stage and the formation of trophectoderm. Green fluorescent protein (GFP) expression was observed in a trophoblast stem (TS) cell line after infection with a GFP-expressing WNV construct. However, no fluorescence was observed in differentiated trophoblast giant cell (TGC) cultures. GFP fluorescence was present in TGC cultures if infected TS cells were induced to differentiate. These results suggest that embryos are susceptible to WNV infection after the formation of the trophectoderm around 3.5 dpc through the formation of the functional placenta around 10.5 dpc.
Descriptors: placenta diseases, West Nile fever, West Nile virus, blastocyst, cell line, green fluorescent proteins, mice, recombinant proteins, stem cells, trophoblasts.

Khairallah, M., S. Ben Yahia, S. Attia, B. Jelliti, S. Zaouali, and A. Ladjimi (2006). Severe ischemic maculopathy in a patient with West Nile virus infection. Ophthalmic Surgery, Lasers and Imaging 37(3): 240-242.
Abstract: A 60-year-old man with diabetes mellitus had a sudden decrease in vision in his right eye 3 weeks after confirmed West Nile virus infection. Visual acuity in the right eye was 20/400. Fundus examination showed bilateral multifocal chorioretinitis, which was associated with proliferative diabetic retinopathy in the right eye and severe nonproliferative diabetic retinopathy in the left eye. There were deep, dense retinal hemorrhages, retinal opacification, and retinal arterial sheathing in the macula of the right eye. Fluorescein angiography revealed extensive capillary nonperfusion in the macular area of the right eye. Six months later, vision remained unchanged and a choroidal neovascularization developed over a chorioretinal scar in the same eye.
Descriptors: chorioretinitis, eye infections, retinal vessels, pathology, West Nile fever complications, chorioretinitis diagnosis, diabetic retinopathy diagnosis, fluorescein angiography, ischemia diagnosis, laser coagulation, vision disorders.

Khairallah, M., S. Ben Yahia, S. Attia, S. Zaouali, B. Jelliti, S. Jenzri, A. Ladjimi, and R. Messaoud (2006). Indocyanine green angiographic features in multifocal chorioretinitis associated with West Nile virus infection. Retina 26(3): 358-359.
Descriptors: chorioretinitis, diagnostic use of coloring agents, eye infections, indocyanine green, West Nile fever diagnosis, viral blood antibodies, chorioretinitis, viral virology, fluorescein angiography, immunoglobulin M blood.

Khosla, J.S., M.J. Edelman, N. Kennedy, and S.G. Reich (2005). West Nile virus presenting as opsoclonus-myoclonus cerebellar ataxia. Neurology 64(6): 1095.
Descriptors: non-small cell lung carcinoma complications, cerebellar ataxia, paraneoplastic syndromes, nervous system, West Nile fever, fatal outcome, immunoglobulin M blood, paraneoplastic syndromes, nervous system diagnosis.

Koevary, S.B. (2005). Ocular involvement in patients infected by the West Nile virus. Optometry St. Louis, Mo. 76(10): 609-612.
Abstract: West Nile virus (WNV), a mosquito-borne RNA virus for which there is no treatment, began emerging as a threat to health in the United States in 1999. Since then, its frequency and apparent clinical severity have increased. Patients with severe disease may experience ocular complications that include pain, vitreous inflammation, nonrelapsing chorioretinitis, retinal vasculitis, chorioretinal scarring, optic neuritis, and retinal hemorrhages. Age appears to be a risk factor for the development of ocular symptoms. Most patients with ocular involvement report floaters or decreased vision. Many ocular inflammatory conditions with an associated underlying systemic cause often present with chorioretinitis. However, the characteristic distribution and linear array or scattered pattern of the chorioretinal lesions seen in WNV is distinctive. The foregoing notwithstanding, other multifocal choroidopathies must be considered including syphilis, ocular histoplasmosis, multifocal choroiditis, tuberculosis, and sarcoid. Although topical steroids were reported to resolve WNV-induced uveitis and its associated keratic precipitates, most cases resolved irrespective of treatment, and relapses were uncommon. It is important for the eye care professional to be alert to the possible presence of WNV, particularly in older patients who present with ocular symptoms during mosquito season. Thus, a thorough ocular evaluation should include a dilated fundus examination and, when indicated, fluorescein angiography should be performed in patients suspected of being infected with WNV.
Descriptors: chorioretinitis, eye infections, viral etiology, optic neuritis, retinal hemorrhage, retinal vasculitis, West Nile fever, complications, age factors, risk factors.

Kraushaar, G., R. Patel, and G.W. Stoneham (2005). West Nile Virus: A case report with flaccid paralysis and cervical spinal cord: MR imaging findings. American Journal of Neuroradiology 26(1): 26-29.
Abstract: We present a case of serologically proved West Nile virus (WNV) flaccid paralysis of the right upper extremity. Radiologic correlation revealed striking T2 hyperintensities in the anterior horns of the cervical spinal cord, similar to those seen in cases of poliomyelitis. Recognition of the MR imaging findings in cases of WNV flaccid paralysis can provide early evidence of infection.
Descriptors: computer assisted image processing, magnetic resonance imaging, spinal cord paralysis, West Nile fever, West Nile virus, anterior horn cells, arm innervation, follow-up studies, motor neuron disease, muscle hypotonia, muscle weakness.

LaBeaud, A.D., M.V. Lisgaris, C.H. King, and A.M. Mandalakas (2006). Pediatric West Nile virus infection: Neurologic disease presentations during the 2002 epidemic in Cuyahoga County, Ohio. Pediatric Infectious Disease Journal 25(8): 751-753.
Abstract: Knowledge is currently limited about West Nile virus (WNV) infection and its sequelae among children. Available evidence suggests that when compared with adults, children less than 18 years old can be at high risk for WNV exposure and infection yet manifest a lower risk for WNV-related morbidity and mortality. We detail clinical features of pediatric West Nile-associated neurologic disease (WNND) epidemic cases in Cuyahoga County during 2002. We present a structured review of pediatric and adult WNND cases hospitalized in Cuyahoga County, Ohio. During the epidemic, 5 children were hospitalized with confirmed WNND (estimated incidence = 1.4/100,000 children 5-17 years old at risk). Compared with adults, children had shorter hospitalization (mean, 4.6 versus 12.3 days), fewer neurologic symptoms, better neurologic outcomes, and lower mortality (0% versus 5.3%). Cerebrospinal fluid results were similar. When compared with adults, children had significantly lower rates of WNND. Children are at a decreased risk for severe WNV and less likely to present with neurologic signs or suffer neurologic sequelae.
Descriptors: viral encephalitis epidemiology, viral meningitis virology, West Nile fever epidemiology, Ohio, children.

Leis, A.A. and D.S. Stokic (2005). Long-term assessment of motor function after severe West Nile virus infection. Neurology 64(6, Suppl. 1): A248. ISSN: 0028-3878.
Descriptors: West Nile virus infection, long term assessment of motor function, muscle weakness, nervous system disease, myelitis, diagnostic techniques.
Notes: Meeting Information: 57th Annual Meeting of the American Academy of Neurology, Miami Beach, Florida, USA; April 9 -19, 2005.

Marciniak, C. and E.L. Rosenfeld (2005). Serial electrodiagnostic studies in West Nile virus-associated acute flaccid paralysis. American Journal of Physical Medicine and Rehabilitation 84(11): 904-910.
Abstract: A man in his 70s presented for acute rehabilitation with severe acute flaccid asymmetric weakness in both lower limbs. Cerebrospinal fluid and serum immunoglobulin M titers were positive for West Nile virus. Electrodiagnostic studies demonstrated severe diffuse motor axonopathy consistent with an anterior myelitis. Electrodiagnostic and clinical improvements were monitored. Electrodiagnostic testing at 6 and 18 mos demonstrated continuing reinnervation; nascent voluntary motor unit action potentials were first noted proximally and, at 18 mos, distally in the left lower limb, including muscles in which motor unit potentials were not initially noted. Corresponding clinical improvements, though slow, were demonstrated even at 1(1/2) yrs after onset. Thus, motoric changes after West Nile virus-associated anterior myelitis need to be monitored over a prolonged time period to allow accurate assessment of prognosis for recovery in rehabilitation programs.
Descriptors: myelitis, West Nile fever complications, West Nile virus isolation and purification, acute disease, viral cerebrospinal fluid, muscle weakness, skeletal muscle, paraplegia rehabilitation, time factors.

Mawhorter, S.D., A. Sierk, S.M. Staugaitis, R.K. Avery, R. Sobecks, R.A. Prayson, G.W. Procop, and B. Yen Lieberman (2005). Fatal West Nile Virus infection after rituximab/fludarabine--induced remission for non-Hodgkin's lymphoma. Clinical Lymphoma and Myeloma 6(3): 248-250.
Abstract: West Nile virus (WNV) infections are potentially life threatening in immunocompromised hosts. Currently, the best diagnostic test is serology. Reverse-transcriptase polymerase chain reaction (RT-PCR) testing has a role, but, because WNV is a cell-associated neurotropic virus, RT-PCR results are frequently negative even in cases of active infection. We present a case in which serology results were persistently negative because the patient was immunocompromised following lymphoma treatment. The role of humoral immunity in resolution of WNV is also discussed.
Descriptors: monoclonal antibodies, administration and dosage, antineoplastic agents, follicular lymphoma, West Nile fever, West Nile virus fatal outcome, lymphoma, follicular drug therapy, remission, vidarabine administration and dosage.

McBride, W., K.R. Gill, and L. Wiviott (2006). West Nile Virus infection with hearing loss. Journal of Infection 53(5): E203-E205.
Abstract: Since the New York outbreak in 1999, West Nile Virus (WNV) has spread across the United States and North America. The spectrum of disease may range from asymptomatic to debilitating neuroinvasive. We present a case of a woman with myasthenia gravis on immunosuppressive therapy who developed WNV meningoencephalitis presenting as flaccid paralysis and severe bilateral hearing loss. To our knowledge this is the first reported case of WNV-associated hearing loss, and the first reported in a patient with previously diagnosed myasthenia gravis. Of epidemiologic interest was that her mother, 81 years old and in previous good health, developed a WNV infection shortly before the patient's infection.
Descriptors: hearing loss, immunocompromised host, West Nile fever, disease transmission, immunosuppressive agents, therapeutic use, myasthenia gravis, WNV meningoencephalitis.

Michaelson, P.G. and E.A. Mair (2005). West Nile virus: A primer for the otolaryngologist. Otolaryngology - Head and Neck Surgery 132(3): 347-352.
Abstract: BACKGROUND: Since recognition in the United States with a 1999 New York City epidemic, West Nile virus has enduringly migrated westward, leaving few states unaffected. Infection rates are rising at an alarming rate, doubling every year since introduction, with more than 9800 cases in 2003 alone and more than 260 deaths. Patients may present with myriad symptoms including a maculopapular rash that affects the face and trunk and diffuse lymphadenopathy, both of which may result in the initial consultation of the otolaryngologist. We review the clinical history of West Nile virus and its epidemiology, laboratory findings, and variable clinical presentation, with an emphasis on otolaryngologic manifestations. STUDY DESIGN AND SETTING COMPREHENSIVE: review of the literature over the past 50 years with an emphasis on what the present-day otolaryngologist needs to know concerning West Nile virus. Clinical manifestations of the head and neck such as encephalitis, meningitis, maculopapular rash, lymphadenopathy and dysphagia are discussed. RESULTS: To date, there are no articles in the otolaryngology literature discussing West Nile virus. These patients may present initially to multiple providers in diverse specialties because of multifarious initial signs and symptoms. The otolaryngologist must be educated on this quickly growing affliction and practice with a high index of suspicion. CONCLUSIONS: In this article we describe the clinical manifestations of West Nile virus, with an emphasis on the otolaryngologic manifestations. The otolaryngologist must become educated about this entity to facilitate preventative measures, adequately treat, and assist other providers in hopeful control and potential eradication of this infectious threat.
Descriptors: West Nile fever diagnosis, West Nile fever epidemiology, otolaryngology.

Montgomery, S.P., J.A. Brown, M. Kuehnert, T.L. Smith, N. Crall, R.S. Lanciotti, A. Macedo de Oliveira, T. Boo, and A.A. Marfin (2006). Transfusion-associated transmission of West Nile virus, United States 2003 through 2005. Transfusion 46(12): 2038-2046.
Abstract: BACKGROUND: National blood donation screening for West Nile virus (WNV) started in June 2003, after the documentation of WNV transfusion-associated transmission (TAT) in 2002. STUDY DESIGN AND METHODS: Blood donations were screened with investigational nucleic acid amplification assays in minipool formats. Blood collection agencies (BCAs) reported screening results to state and local public health authorities. Donor test results and demographic information were forwarded to CDC via ArboNET, the national electronic arbovirus surveillance system. State health departments and BCAs also reported suspect WNV TATs to CDC, which investigated these reports to confirm WNV infection in blood transfusion recipients in the absence of likely mosquito exposure. RESULTS: During 2003 to 2005, a total of 1,425 presumptive viremic donors were reported to CDC from 41 states. Of 36 investigations of suspected WNV TAT in 2003, 6 cases were documented. Estimated viremia levels were available for donations implicated in four TAT cases; the median estimated viremia was 0.1 plaque-forming units (PFUs) per mL (range, 0.06-0.50 PFU/mL; 1 PFU equals approximately 400 copies/mL). CONCLUSIONS: National blood screening for WNV identified and removed more than 1,400 potentially infectious blood donations in 2003 through 2005. Despite the success of screening in 2003, some residual WNV TAT risk remained due to donations containing very low levels of virus. Screening algorithms employing selected individual-donation testing were designed to address this residual risk and were fully implemented in 2004 and 2005. Continued vigilance for TAT will evaluate the effectiveness of these strategies.
Descriptors: blood donation, West Nile virus, transfusion transmission, blood collection, viremic donors, surveillance system, screening.

Moon, T.D., A. Nadimpalli, E.B. Martin, M.A. Ortiz, and R.B. Van Dyke (2005). Balance and gait abnormalities of a child with West Nile virus infection. Pediatric Infectious Disease Journal 24(6): 568-570.
Abstract: We describe a case of a previously healthy 2-year-old female patient with rash, fever and vomiting for 10 days who presented for medical attention with acute profound balance and gait disturbances and intentional movement dysmetria. West Nile virus-specific IgM and IgG antibodies were detected in the patient's cerebrospinal fluid.
Descriptors: movement disorders, West Nile fever physiopathology, West Nile virus, children, gait, immunoglobulin G cerebrospinal fluid, immunoglobulin M cerebrospinal fluid, musculoskeletal equilibrium.

Murray, K., S. Baraniuk, M. Resnick, R. Arafat, C. Kilborn, K. Cain, R. Shallenberger, T.L. York, D. Martinez, J.S. Hellums, D. Hellums, M. Malkoff, N. Elgawley, W. McNeely, S.A. Khuwaja, and R.B. Tesh (2006). Risk factors for encephalitis and death from West Nile virus infection. Epidemiology and Infection 134(6): 1325-1332.
Abstract: We conducted a nested case-control study to determine potential risk factors for developing encephalitis from West Nile virus (WNV) infection. Retrospective medical chart reviews were completed for 172 confirmed WNV cases hospitalized in Houston between 2002 and 2004. Of these cases, 113 had encephalitis, including 17 deaths, 47 had meningitis, and 12 were fever cases; 67% were male. Homeless patients were more likely to be hospitalized from WNV compared to the general population. A multiple logistic regression model identified age [odds ratio (OR) 1.1, P<0.001], history of hypertension, including those cases taking hypertension-inducing drugs (OR 2.9, P=0.012), and history of cardiovascular disease (OR 3.5, P=0.061) as independent risk factors for developing encephalitis from WNV infection. After adjusting for age, race/ethnicity (being black) (OR 12.0, P<0.001), chronic renal disease (OR 10.6, P<0.001), hepatitis C virus (OR 23.1, P=0.0013), and immunosuppression (OR 3.9, P=0.033) were identified as risk factors for death from WNV infection.
Descriptors: West Nile virus, risk factors, encephalitis control study, fever, meningitis, age, immunosuppression.

Murtagh, B., Y. Wadia, G. Messner, P. Allison, Y. Harati, and R. Delgado (2005). West Nile virus infection after cardiac transplantation. Journal of Heart and Lung Transplantation 24(6): 774-776.
Abstract: West Nile virus is a mosquito-borne RNA Flavivirus infection transmitted to humans and other vertebrates, mainly by the Culex species of mosquito. Since the mid-1990s, the frequency and apparent clinical severity of West Nile virus outbreaks have increased. We report the case of a patient who developed West Nile virus encephalitis shortly after undergoing cardiac transplantation. Clinicians should be aware of the possibility of West Nile virus infection in transplant recipients and in patients receiving blood transfusions.
Descriptors: blood transfusion, adverse effects, heart transplantation, West Nile fever etiology, middle aged humans.

Myers, J.P., T.K. Leveque, and M.W. Johnson (2005). Extensive chorioretinitis and severe vision loss associated with West Nile virus meningoencephalitis. Archives of Ophthalmology 123(12): 1754-1756.
Descriptors: blindness, chorioretinitis, viral eye infections, West Nile fever complications, West Nile virus isolation and purification, electroretinography, fluorescein angiography, meningoencephalitis.

O'Leary, D.R., S. Kuhn, K.L. Kniss, A.F. Hinckley, S.A. Rasmussen, W.J. Pape, L.K. Kightlinger, B.D. Beecham, T.K. Miller, D.F. Neitzel, S.R. Michaels, G.L. Campbell, R.S. Lanciotti, and E.B. Hayes (2006). Birth outcomes following West Nile Virus infection of pregnant women in the United States: 2003-2004. Pediatrics 117(3): E537-E545.
Abstract: BACKGROUND: Congenital West Nile virus (WNV) infection was first described in a single case in 2002. The proportion of maternal WNV infections resulting in congenital infection and clinical consequences of such infections are unknown. METHODS: In 2003 and 2004, women in the United States who acquired WNV infection during pregnancy were reported to the Centers for Disease Control and Prevention by state health departments. Data on pregnancy outcomes were collected. One of the maternal WNV infections was identified retrospectively after the infant was born. Maternal sera, placenta, umbilical cord tissue, and cord serum were tested for WNV infection by using serologic assays and reverse-transcription polymerase chain reaction. Infant health was assessed at delivery and through 12 months of age. RESULTS: Seventy-seven women infected with WNV during pregnancy were clinically followed in 16 states. A total of 71 women delivered 72 live infants; 4 women had miscarriages, and 2 had elective abortions. Of the 72 live infants, 67 were born at term, and 4 were preterm; gestational age was unknown for 1. Of 55 live infants from whom cord serum was available, 54 tested negative for anti-WNV IgM. One infant born with umbilical hernia and skin tags had anti-WNV IgM in cord serum but not in peripheral serum at age 1 month. An infant who had no anti-WNV IgM in cord blood, but whose mother had WNV illness 6 days prepartum, developed WNV meningitis at age 10 days. Another infant, whose mother had acute WNV illness at delivery, was born with a rash and coarctation of the aorta and had anti-WNV IgM in serum at 1 month of age; cord serum was not available. A fourth infant, whose mother had onset of WNV illness 3 weeks prepartum that was not diagnosed until after delivery, had WNV encephalitis and underlying lissencephaly detected at age 17 days and subsequently died; cord serum was not available. The following major malformations were noted among live-born infants: aortic coarctation (n = 1); cleft palate (n = 1); Down syndrome (n = 1); lissencephaly (n = 1); microcephaly (n = 2); and polydactyly (n = 1). One infant had glycogen storage disease type 1. Abnormal growth was noted in 8 infants. CONCLUSIONS: Of 72 infants followed to date in 2003 and 2004, almost all seemed normal, and none had conclusive laboratory evidence of congenital WNV infection. Three infants had WNV infection that could have been congenitally acquired. Seven infants had major malformations, but only 3 of these had defects that could have been caused by maternal WNV infection based on the timing of the infections and the sensitive developmental period for the specific malformations, and none had any conclusive evidence of WNV etiology. However, the sensitivity and specificity of IgM testing of cord blood to detect congenital WNV infection are currently unknown, and congenital WNV infection among newborns with IgM-negative serology cannot be ruled out. Prospective studies comparing pregnancy outcomes of WNV-infected and -uninfected women are needed to better define the outcomes of WNV infection during pregnancy.
Descriptors: pregnancy complications, West Nile fever, children, vertical disease transmission, fetal blood, immunoglobulin M analysis, human milk, viral RNA analysis, West Nile virus isolation and purification.
Notes: Comment In: Pediatrics. 2006 Mar;117(3):936-9.

Orton, S.L., S.L. Stramer, and R.Y. Dodd (2006). Self-reported symptoms associated with West Nile virus infection in RNA-positive blood donors. Transfusion 46(2): 272-277.
Abstract: BACKGROUND: In 2003, West Nile virus (WNV) nucleic acid amplification testing (NAT) was implemented to detect potentially infected donors. Of more than 5.3 million donations screened prospectively by the American Red Cross during the epidemic periods of 2003 and 2004, 974 were NAT-reactive and 519 confirmed-positive. A subset of both the confirmed-positive and the false-positive groups was assessed for demographic characteristics, symptoms, and symptom reporting relative to date of donation. STUDY DESIGN AND METHODS: All donors with initial WNV NAT-reactive results were invited to participate in a study that included a demographic, symptom, and date-of-symptom questionnaire. WNV confirmed-positive cases were compared to false-positive controls for comparison of frequency of symptom reporting before, on the day of, and after donation. RESULTS: Enrolled cases and controls were similar in all characteristics except cases were more likely to live in rural areas. Symptoms were reported by 61 percent of cases versus 20 percent of controls, with 74 percent of symptoms reported by cases within the 14 days after donation. The frequency of headache and fever reported together in the 7 days before donation was not significantly different between cases and controls; only the individual frequencies of headache, eye pain, and new rash during this time were significantly different. The most commonly reported symptoms, after adjustment for symptom reporting by controls, were headache, new rash, and generalized weakness; these symptoms were reported by 25 percent of cases. CONCLUSIONS: The demographic characteristics of infected donors reflected the rural nature of the 2003 to 2004 WNV epidemics. This study suggests that asking donors about predonation headache and fever had no detectable contribution to blood safety.
Descriptors: blood donors, West Nile fever diagnosis, West Nile virus, fever, headache, logistic models, mass screening, middle aged humans, multivariate analysis, viral RNA.

Ou, A.C. and R.C. Ratard (2005). One-year sequelae in patients with West Nile Virus encephalitis and meningitis in Louisiana. Journal of the Louisiana State Medical Society 157(1): 42-46.
Abstract: West Nile Virus (WNV) infection can be severe and complicated by neuroinvasive disease, such as meningitis and encephalitis. Not much is known about the one-year sequelae following a complicated WNV infection. From July to December 2002, the first large outbreak of WNV in the Southern United States occurred in Louisiana. This epidemic resulted in 329 cases of WNV infection including 125 cases of West Nile fever and 204 cases complicated by meningitis and encephalitis. One year later, during the fall of 2003, a telephone survey was conducted to understand the one-year effects of severe WNV infections. WNV case fatality rate was 19.6%. Death certificates of all the deceased were reviewed to verify the mortality rate from WNV infection. The telephone survey revealed that one-year sequelae from severe WNV infections are common and can affect the body and mind. In addition, it can change a person's perception of the state of their health.
Descriptors: meningitis, West Nile fever, West Nile virus, viral antibodies, disease outbreaks, enzyme linked immunosorbent assay, Louisiana, retrospective studies, survival rate.

Paisley, J.E., A.F. Hinckley, D.R. O'Leary, W.C. Kramer, R.S. Lanciotti, G.L. Campbell, and E.B. Hayes (2006). West Nile virus infection among pregnant women in a northern Colorado community, 2003 to 2004. Pediatrics 117(3): 814-820.
Abstract: OBJECTIVE: Since West Nile virus (WNV) was first detected in New York in 1999, it has spread across North America and become a major public health concern. In 2002, the first documented case of intrauterine WNV infection was reported, involving an infant with severe brain abnormalities. To determine the frequencies of WNV infections during pregnancy and of intrauterine WNV infections, we measured WNV-specific antibodies in cord blood from infant deliveries after a community-wide epidemic of WNV disease. METHODS: Five hundred sixty-six pregnant women who presented to Poudre Valley Hospital (Fort Collins, CO) for delivery between September 2003 and May 2004 provided demographic and health history data through self-administered questionnaires and hospital admission records. Umbilical cord blood was collected from 549 infants and screened for WNV-specific IgM and IgG antibodies with enzyme-linked immunosorbent assays, with confirmation by plaque-reduction neutralization tests. Newborn growth parameters, Apgar scores, and hearing test results were recorded. RESULTS: Four percent (95% confidence interval: 2.4-5.7%) of cord blood samples tested positive for WNV-specific IgG antibodies. No cord blood samples were positive for WNV-specific IgM antibodies. There were no significant differences between infants of seropositive and seronegative mothers with respect to any of the growth parameters or outcomes measured. CONCLUSIONS: Intrauterine WNV infections seemed to be infrequent. In our study, WNV infection during pregnancy did not seem to affect adversely infant health at birth. Larger prospective studies are necessary to measure more completely the effects of maternal WNV infection on pregnancy and infant health outcomes.
Descriptors: pregnancy complications, infectious epidemiology, West Nile fever, Colorado, fetal blood, immunoglobulin A blood, immunoglobulin G blood, children, seroepidemiologic studies, West Nile virus isolation and purification.

Pergam, S.A., C.E. Delong, L. Echevarria, G. Scully, and D.E. Goade (2006). Myocarditis in west nile virus infection. American Journal of Tropical Medicine and Hygiene 75(6): 1232-1233. ISSN: 0002-9637.
Abstract: West Nile virus (WNV) myocarditis has been documented pathologically in birds and mammals but has rarely been reported in human clinical syndromes. We describe myocarditis associated with WNV.
Descriptors: West Nile virus, myocarditis, birds, mammals, clinical syndromes, humans.

Petropoulou, K.A., S.M. Gordon, R.A. Prayson, and P.M. Ruggierri (2005). West Nile virus meningoencephalitis: MR imaging findings. American Journal of Neuroradiology 26(8): 1986-1995.
Abstract: BACKGROUND AND PURPOSE: Reports of MR imaging in West Nile virus (WNV) meningoencephalomyelitis are few and the described findings limited. The purpose of this study was to review the spectrum of MR imaging findings for WNV meningoencephalomyelitis and investigate whether any of the findings correlates with clinical presentation of flaccid paralysis. METHODS: We reviewed the MR imaging findings of 17 patients with confirmed WNV encephalitis and/or myelitis. MR imaging brain studies were evaluated for location of signal intensity abnormalities, edema, hydrocephalus, or abnormal enhancement. MR imaging spine studies were evaluated for signal intensity abnormalities in cord and/or enhancement. RESULTS: Retrospective review of the MR imaging studies of 17 patients was performed by 2 neuroradiologists. Eleven of 16 brain MR images demonstrated abnormalities. Eight (50%) patients had abnormal studies related to meningoencephalitis. All 8 patients had abnormal findings in the deep gray matter and/or brain stem; 2 had additional white matter abnormalities. Three patients with abnormal MR studies of the spine had extremity weakness on examination. The imaging findings included abnormal signal intensity more pronounced in the ventral horns and/or enhancement around the conus medullaris and cauda equina. One patient had additional abnormalities in the pons. CONCLUSION: Abnormal MR imaging findings in patients with WNV meningoencephalomyelitis are nonspecific but not uncommon. Anatomic areas commonly affected are basal ganglia, thalami, mesial temporal structures, brain stem, and cerebellum. Extremity weakness or flaccid paralysis corresponds to spinal cord/cauda equina abnormalities.
Descriptors: magnetic resonance imaging, meningoencephalitis, West Nile fever, brain pathology, extremities, muscle weakness, paraplegia, retrospective studies, spinal cord, humans.

Prasad, S., M.J. Brown, and S.L. Galetta (2006). Transient downbeat nystagmus from West Nile virus encephalomyelitis. Neurology 66(10): 1599-1600.
Descriptors: pathologic nystagmus etiology, West Nile fever, brain stem, electromyography, ocular motility disorders, quadriplegia, abnormal reflex.

Saad, M., S. Youssef, D. Kirschke, M. Shubair, D. Haddadin, J. Myers, and J. Moorman (2005). Acute flaccid paralysis: The spectrum of a newly recognized complication of West Nile virus infection. Journal of Infection 51(2): 120-127.
Abstract: OBJECTIVES: Acute flaccid paralysis (AFP) has recently emerged as a major central nervous system complication associated with West Nile virus (WNV) infection. The spectrum of clinical presentations of AFP in WNV infection and its sequelae have not been well-studied. METHODS: We describe three patients with AFP due to WNV infection and review the clinical presentations of 56 patients with this complication derived from published studies. RESULTS: Patients with AFP and WNV presented with a spectrum of illness ranging from single extremity paralysis to quadriparalysis with cranial nerve involvement. Patients commonly developed respiratory failure (54%) and bladder dysfunction (22%). While fever was nearly universal (92%), signs of meningismus were less common (17%). Cerebrospinal fluid (CSF) analysis generally revealed a modest pleocytosis, and imaging studies were not diagnositic. Persistent neurologic impairment occurred in all survivors; overall mortality rate was high (22%) and was associated with both the extent of paralysis and advanced age. CONCLUSION: AFP in the setting of WNV is associated with significant mortality and long-term morbidity.
Descriptors: acute flaccid paralysis, West Nile fever complications, viral blood antibodies, muscle hypotonia, quadriplegia, West Nile virus.

Schafernak, K.T. and E.H. Bigio (2006). West Nile virus encephalomyelitis with polio-like paralysis & nigral degeneration. Canadian Journal of Neurological Sciences 33(4): 407-410.
Abstract: BACKGROUND: Patients infected with West Nile virus (WNV) may develop acute neurologic disease, which can be severe or even fatal, including WNV meningitis, encephalitis, and an irreversible acute flaccid paralysis or poliomyelitis-like syndrome. Movement disorders have also been described. REPORT: We report combined neuronal loss, gliosis, and neurofibrillary tangle formation in the substantia nigra of a 41-year-old man with a history of WNV encephalomyelitis and poliomyelitis-like paralysis. CONCLUSIONS: Clinically our patient did not display parkinsonism, however, it is interesting to speculate whether, in the absence of the residual subacute poliomyelitis-like syndrome, the neuropathologic findings could have eventually evolved clinically into WNV-associated postencephalitic parkinsonism.
Descriptors: West Nile virus infection, neurologic disease, meningitis, encephalitis, flaccid paralysis, movement disorders, poliomyelitis like paralysis.

Sejvar, J.J., A.V. Bode, A.A. Marfin, G.L. Campbell, D. Ewing, M. Mazowiecki, P.V. Pavot, J. Schmitt, J. Pape, B.J. Biggerstaff, and L.R. Petersen (2005). West Nile virus-associated flaccid paralysis. Emerging Infectious Diseases 11(7): 1021-1027. ISSN: 1080-6040.
Abstract: The causes and frequency of acute paralysis and respiratory failure with West Nile virus (WNV) infection are incompletely understood. During the summer and fall of 2003, we conducted a prospective, population-based study among residents of a 3-county area in Colorado, United States, with developing WNV-associated paralysis. Thirty-two patients with developing paralysis and acute WNV infection were identified. Causes included a poliomyelitislike syndrome in 27 (84%) patients and a Guillain-Barre-like syndrome in 4 (13%); 1 had brachial plexus involvement alone. The incidence of poliomyelitislike syndrome was 3.7/100,000. Twelve patients (38%), including 1 with Guillain-Barre-like syndrome, had acute respiratory failure that required endotracheal intubation. At 4 months, 3 patients with respiratory failure died, 2 remained intubated, 25 showed various degrees of improvement, and 2 were lost to followup. A poliomyelitislike syndrome likely involving spinal anterior horn cells is the most common mechanism of WNV-associated paralysis and is associated with significant short- and long-term illness and death.
Descriptors: muscle hypotonia, paralysis, West Nile fever complications, humans, guillain barre syndrome, respiratory insufficiency virology, cerebrospinal fluid.

Sejvar, J.J., A.V. Bode, A.A. Marfin, G.L. Campbell, J. Pape, B.J. Biggerstaff, and L.R. Petersen (2006). West Nile Virus-associated flaccid paralysis outcome. Emerging Infectious Diseases 12(3): 514-516. ISSN: 1080-6040 .
Abstract: We report 1-year follow-up data from a longitudinal prospective cohort study of patients with West Nile virus-associated paralysis. As in the 4-month follow-up, a variety of recovery patterns were observed, but persistent weakness was frequent. Respiratory involvement was associated with considerable illness and death.
Descriptors: muscle hypotonia, paralysis, West Nile fever, follow up studies, artificial respiration, respiratory insufficiency, mortality.

Skupski, D.W., G.S. Eglinton, A.D. Fine, E.B. Hayes, and D.R. O'Leary (2006). West Nile virus during pregnancy: A case study of early second trimester maternal infection. Fetal Diagnosis and Therapy 21(3): 293-295.
Abstract: A woman who contracted West Nile virus (WNV) neuroinvasive illness during her second trimester subsequently elected to terminate her pregnancy due to concerns of possible adverse effects of WNV on her developing fetus. Consent was obtained to test maternal and post-mortem fetal tissues for WNV infection. Fetal blood, liver, kidneys, spleen, umbilicus and amniotic fluid were negative for WNV RNA by polymerase chain reaction and negative for WNV IgM antibodies by ELISA, indicating that in this case there was no evidence of WNV transmission to the fetus. Until further information regarding outcomes of WNV infection during pregnancy is available, pregnant women in areas where WNV is transmitted should take precautions to avoid mosquito bites. Women with WNV illness during pregnancy should undergo regular prenatal checkups including ultrasound examinations to assess fetal development, and healthcare providers should promptly report cases of WNV in pregnant women to their state or local health department or to CDC. Copyright 2006 S. Karger AG, Basel.
Descriptors: pregnancy complications, West Nile fever, induced abortion, amniotic fluid, vertical disease transmission, fetal blood, gestational age, kidney, liver.

Steele, N.P. and D. Myssiorek (2006). West Nile virus induced vocal fold paralysis. Laryngoscope 116(3): 494-496.
Abstract: OBJECTIVE: West Nile virus has recently become a public health concern in the United States, after an outbreak in New York City in 1999. It is a mosquito-borne virus that causes a spectrum of disease from flu-like symptoms to encephalopathy, muscle weakness, and, in some cases, death. STUDY DESIGN: Case Report. METHODS: A patient infected with West Nile virus presented with progressive muscle weakness, and later developed bilateral vocal fold paresis. His clinical presentation, physical and laboratory examination findings, and course of illness will be discussed. RESULTS: After a prolonged hospital stay, and presumptive treatment for Guillain-Barre, repeat CSF analysis revealed infection with the West Nile virus. The patient developed bilateral vocal fold paralysis during his hospital course. At long-term follow-up, the patient's left vocal fold paralysis persisted, while the right vocal fold paralysis had resolved. CONCLUSIONS: Although several viruses have been associated with recurrent laryngeal nerve injury, this is the first report of West Nile virus induced vocal fold paralysis.
Descriptors: vocal cord paralysis, West Nile fever complications, West Nile virus, disease diagnosis, fiber optics endoscopy, follow-up studies, stroboscopy.

Teperman, L.W., T. Diflo, A. Fahmy, G.R. Morgan, R.E. Wetherbee, L. Ratner, D. Cohen, J. Ackelsberg, E. Debernardo, A. Fine, E. Lumeng, N.P. Tavakoli, B. Dixon, A. Weltman, and B. Tsoi (2005). West Nile virus infections in organ transplant recipients New York and Pennsylvania, August-September, 2005. Morbidity and Mortality Weekly Report 54(40): 1021-1023. ISSN: 0149-2195.
Descriptors: West Nile virus infection, organ transplant recipients, neuroinvasive disease, liver transplantation, kidney transplantation, clinical techniques, lung transplantation.

Ward, M.P., J.A. Schuermann, L.D. Highfield, and K.O. Murray (2006). Characteristics of an outbreak of West Nile virus encephalomyelitis in a previously uninfected population of horses. Veterinary Microbiology 118(3-4): 255-259.
Abstract: Equine West Nile virus (WNV) encephalomyelitis cases - based on clinical signs and ELISA serology test results - reported to Texas disease control authorities during 2002 were analyzed to provide insights into the epidemiology of the disease within a previously disease-free population. The epidemic occurred between June 27 and December 17 (peaking in early October) and 1,698 cases were reported. Three distinct epidemic phases were identified, occurring mostly in southeast, northwest and then central Texas. Significant (P<0.05) disease clusters were identified in northwest and northern Texas. Most (91.1%) cases had no recent travel history, and most (68.9%) cases had not been vaccinated within the previous 12 months. One-third of cases did not survive, 71.2% of which were euthanatized. The most commonly reported presenting signs included ataxia (69%), abnormal gait (52%), muscle fasciculations (49%), depression (32%) and recumbency (28%). Vaccination status, ataxia, falling down, recumbency and lip droop best explained the risk of not surviving WNV disease. Results suggest that the peak risk period for encephalomyelitis caused by WNV may vary substantially among regions within Texas. Recumbent horses have a poor prognosis for survival. Vaccines, even if not administered sufficiently in advance of WNV infection within a district, may reduce the risk of death by at least 44%.
Descriptors: West Nile virus, horses, infection, clinical signs, Texas, prognosis, vaccines, death, depression, ataxia, recumbancy.

Watson, N.K., R.E. Bartt, S.A. Houff, S.E. Leurgans, and M.J. Schneck (2005). Focal neurological deficits and West Nile virus infection. Clinical Infectious Diseases 40(7): E59-E62.
Abstract: Our experience with West Nile virus infection revealed that 54% of 28 patients had a focal neurological deficit at presentation. A meningitis or encephalitis syndrome was absent in 47% of patients with focal deficits. Details of the variety of deficits, the time to development of deficits, and the associated radiological and laboratory findings are also discussed in the present report.
Descriptors: nervous system diseases, West Nile fever complications, humans.

Wesson, D.M. (2006). Is West Nile virus a teratogen? Birth Defects Research 76(5): 357. ISSN: 1542-0752.
Descriptors: West Nile virus, obstetrics, teratogen, nervous system disease, viral disease etiology, pregnancy, immunosuppression.
Notes: Meeting Information: 46th Annual Meeting of the Teratology Society, Tucson, Arizona, USA; June 24 -29, 2006.

Whitney, E.A., K.L. Heilpern, C.W. Woods, C.C. Bahn, E.A. Franko, C. Del Rio, B.J. Silk, J.J. Ratcliff, K.A. Bryant, M.M. Park, S.J. Watkins, L.B. Caram, H.M. Blumberg, and R.L. Berkelman (2006). West Nile virus among hospitalized, febrile patients: A case for expanding diagnostic testing. Vector Borne and Zoonotic Diseases 6(1): 42-49. ISSN: 1530-3667.
Abstract: In Georgia, most individuals reported with West Nile virus (WNV) disease have been diagnosed with West Nile neuroinvasive disease (WNND). Relatively few cases of West Nile Fever (WNF) are reported, and the burden of illness due to WNV is likely underestimated. From July through October 2003, WNV serologic testing was performed on enrolled patients>or=18 years of age with fever admitted to a large, urban hospital in Atlanta, Georgia through the emergency department (ED). Patients' history, clinical, and laboratory data were recorded. Residual blood drawn in the ED was tested to determine the presence of WNV IgG and IgM antibodies. Of 254 patients tested for WNV, four (1.6%) patients were positive for WNV IgM and IgG antibodies, and had a clinical illness compatible with WNV. None of the four positive patients were clinically suspected of having WNV infection; discharge diagnoses included pneumonia, migraine, stroke, and gout. These four patients accounted for 80% of all WNV diagnosed in this hospital, 44% of all cases in Fulton County, and 7% of all cases reported in Georgia in 2003. The occurrence of WNV disease may be substantially greater than currently reflected in disease statistics in Georgia and many other states. When indicators of WNV activity are present and patients are likely to have had intensive mosquito exposure, WNV should be considered in the differential diagnosis of seriously ill, febrile patients.
Descriptors: West Nile virus, febrile patients, diagnostic testing, neuroinvasive disease, mosquitoe exposure, differential diagnosis.

Wu, J.J., D.B. Huang, and S.K. Tyring (2006). West Nile virus rash on the palms and soles of the feet. Journal of the European Academy of Dermatology and Venereology 20(10): 1393-1394.
Descriptors: West Nile virus, rash, palms, soles, feet.


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