Treatment for West Nile Virus Infection
There is no FDA-approved specific antiviral therapy for West Nile virus infection; treatment consists entirely of supportive care with intravenous fluids, electrolyte supplementation, and nutritional support. 1
Primary Treatment Approach
Supportive care is the only available treatment for WNV infection, as no evidence-based therapies or human vaccines exist for this disease. 1, 2
Management focuses on:
Hospitalization rates exceed 85% in all age groups with neuroinvasive disease, reaching 98% in patients aged ≥70 years. 3
Special Treatment Considerations
Acute Disseminated Encephalomyelitis (ADEM)
High-dose intravenous corticosteroids (methylprednisolone 1g IV daily for 3-5 days) are generally recommended for ADEM associated with WNV infection. 1
This represents the only specific therapeutic intervention with guideline support for any WNV complication. 1
Neurologic Monitoring
EEG should be performed in patients with undiagnosed encephalopathy to rule out non-convulsive status epilepticus. 4
CSF analysis is important for confirming neuroinvasive disease when IgM antibodies to WNV are detected in cerebrospinal fluid. 1
Special Populations
Pregnant Women
No specific treatment modifications exist for pregnant women with WNV infection. 1, 5
Detailed ultrasound examination of the fetus should be considered 2-4 weeks after onset of WNV illness to evaluate for structural abnormalities. 1, 5
Testing of amniotic fluid, chorionic villi, or fetal serum may be considered, though sensitivity and specificity are unknown. 1, 5
In cases of miscarriage or induced abortion, test all products of conception (placenta, umbilical cord) for evidence of infection. 5
Immunocompromised Patients
Mortality reaches 30-40% in patients with hematologic malignancies, solid organ transplants, and those receiving B-cell-depleting monoclonal antibodies. 2
These patients may have prolonged viremia and delayed immune response, requiring extended supportive care. 1
Clinical Pitfalls and Caveats
The case fatality rate for neuroinvasive disease is approximately 10% overall but increases to 20% in individuals ≥70 years old. 2
More than 50% of hospitalized patients develop long-term sequelae including fatigue, weakness, myalgia, memory loss, and depression. 2
30-40% of patients hospitalized for WNV disease are discharged to long-term care facilities, indicating the severity of residual disability. 2
Despite intensive research over 20 years, no approved vaccines or specific treatments exist for humans, making prevention through mosquito avoidance the only effective strategy. 6