ICD-10 Code A08.31 – Calicivirus enteritis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A08.31 – Calicivirus enteritis
What it is
A08.31 identifies enteritis caused by calicivirus, a viral infection of the intestines. It is used when the record documents calicivirus as the cause of the gastrointestinal illness.
Clinical signs
Typical findings include acute diarrhea, vomiting, nausea, and abdominal discomfort. Clinical features vary; refer to documentation for the specific presentation and any confirmed viral cause.
When to use this code
Use this code when the provider documents calicivirus enteritis or clearly attributes the intestinal infection to calicivirus. It may be appropriate in acute gastroenteritis cases with confirmed viral etiology. If the note only says “viral enteritis,” check documentation before assigning A08.31.
Do not use for
Do not use this code for unspecified gastroenteritis, nor for enteritis from another confirmed organism. If the record does not identify calicivirus, check documentation and code the documented diagnosis instead.
Coding tip
Code A08.31 only when calicivirus is explicitly documented as the cause of enteritis.