ICD-10 Code J09.X3 – Influenza due to identified novel influenza A virus with gastrointestinal manifestations (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J09.X3 – Influenza due to identified novel influenza A virus with gastrointestinal manifestations
What it is
This code identifies influenza caused by an identified novel influenza A virus when gastrointestinal symptoms are present. Use it for documented novel influenza A infections with stomach or intestinal involvement.
Clinical signs
Clinical features may include influenza-like illness plus nausea, vomiting, diarrhea, or abdominal discomfort. You should rely on documentation of both the novel influenza A infection and the gastrointestinal manifestations.
When to use this code
Use J09.X3 when the provider documents influenza due to an identified novel influenza A virus and specifically notes gastrointestinal manifestations. It also fits when the record links GI symptoms to the influenza diagnosis. If the chart only says influenza without the novel virus type, check documentation.
Do not use for
Do not use this code for seasonal influenza, unspecified influenza, or influenza without documented gastrointestinal manifestations. If the virus type or symptom link is unclear, check documentation.
Coding tip
Code only when the chart clearly identifies the novel influenza A virus and the GI manifestation.