ICD-10 Code A92.3 – West Nile virus infection (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A92.3 – West Nile virus infection
What it is
A92.3 identifies West Nile virus infection, a mosquito-borne viral illness that can range from mild fever to serious neurologic disease. Use this code when documentation confirms West Nile virus infection.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include fever, headache, body aches, rash, and, in severe cases, meningitis, encephalitis, or acute flaccid weakness.
When to use this code
Use A92.3 when the provider documents West Nile virus infection, with or without neurologic involvement. It also fits confirmed cases noted as West Nile fever or West Nile neuroinvasive disease, if the record supports the diagnosis. Check documentation when the chart only says suspected arboviral illness.
Do not use for
Do not use this code for ruled-out infection, nonspecific viral syndrome, or exposure without confirmed disease. If the record names a different mosquito-borne arboviral infection, code that condition instead.
Coding tip
Code from the provider’s final diagnosis and add any documented neurologic manifestation only when supported by the record.