ICD-10-CM 2027
ICD-10 code for Norovirus enteritis
Acute gastroenteropathy due to Norwalk agent
From the official ICD-10-CM alphabetic index entry “Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective) › norovirus”. Page updated September 29, 2026.
About coding Norovirus enteritis
The ICD-10-CM code for Norovirus enteritis is A08.11 (Acute gastroenteropathy due to Norwalk agent).
Within A08.1 (acute gastroenteropathy due to Norwalk agent and other small round viruses), A08.11 is specifically for acute gastroenteropathy due to Norwalk agent. Related codes cover other small round viruses (A08.19).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC, relative weight 1.2392) and DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC, relative weight 0.7645), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Norovirus enteritis ICD-10 codes
What is the ICD-10 code for Norovirus enteritis?
- A08.11 — Acute gastroenteropathy due to Norwalk agent.
Is A08.11 billable?
- Yes. A08.11 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A08.11 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A08.11 as a principal diagnosis.
Is A08.11 a CC or MCC?
- A08.11 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.