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In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection
Published on: November 27, 2014
West Nile virus: pathogenesis and therapeutic options
Juan Gea-Banacloche1, Richard T Johnson, Anto Bagic
1National Cancer Institute, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA. banacloj@mail.nih.gov
Annals of Internal Medicine
|April 8, 2004
Summary
West Nile virus causes encephalitis, a zoonotic disease transmitted by mosquitoes. While humans are accidental hosts, severe neurologic illness and human-to-human transmission highlight its public health threat.
Area of Science:
- Virology
- Epidemiology
- Neurology
Background:
- West Nile virus (WNV), a Flaviviridae family member, is prevalent in the United States.
- It is a leading cause of viral encephalitis, with over 9,000 cases and 200 deaths reported in 2003.
- WNV is a zoonosis with a life cycle involving birds (hosts) and mosquitoes (vectors).
Observation:
- Humans are accidental hosts, with transient viremia insufficient for viral propagation.
- Human-to-human transmission is documented via blood, organ transplantation, and lactation.
- The current epidemic suggests a more neurovirulent WNV strain, causing severe neurologic disease.
Findings:
- Encephalitis with weakness is the characteristic presentation.
- Magnetic resonance imaging (MRI) may reveal characteristic deep gray matter nuclei involvement.
- Diagnosis relies on serologic tests, with polymerase chain reaction (PCR) potentially positive in cerebrospinal fluid early on.
Implications:
- Cross-reactivity with other flaviviruses requires caution in serologic test interpretation.
- No current therapeutic intervention shows consistent clinical efficacy for West Nile virus disease.
- Interferon-alpha2b, specific immunoglobulins, and new drug development show therapeutic promise; a vaccine is under development.
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