ICD-10 Code A98.1 – Omsk hemorrhagic fever (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A98.1 – Omsk hemorrhagic fever
What it is
A98.1 identifies Omsk hemorrhagic fever, a viral hemorrhagic fever caused by the Omsk hemorrhagic fever virus. Use it when the diagnosis is documented and the condition is being coded as a confirmed infectious disease.
Clinical signs
Clinical features vary; refer to documentation. Standard descriptions include acute fever, headache, myalgia, and hemorrhagic manifestations, with possible neurologic or respiratory involvement in severe cases.
When to use this code
Use A98.1 when the provider documents Omsk hemorrhagic fever, including suspected-to-confirmed cases in the record if your setting allows coding from documented diagnosis. It also fits encounter notes focused on evaluation, monitoring, or follow-up for this specific viral hemorrhagic fever.
Check documentation if the chart only says “viral fever,” “hemorrhagic fever,” or another arboviral illness without naming Omsk hemorrhagic fever. Code the named condition, not a broader symptom description.
Do not use for
Do not use A98.1 for nonspecific fever, routine viral illness, or other hemorrhagic fevers unless Omsk hemorrhagic fever is explicitly documented. Check documentation for the exact diagnosis.
Coding tip
Verify the organism-specific diagnosis in the assessment or discharge summary before assigning A98.1.