ICD-9-CM Diagnosis Code 488.1
Diagnosis Code: 488.1 (Raw: 4881)
Description: Flu dt iden H1N1 virus
Classification: International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)
Fiscal Year: 2026 Reference
CMS Section 111 Status: Valid for reporting.
Overview & Historical Usage
ICD-9-CM code 488.1 is designated for Flu dt iden H1N1 virus. While superseded by ICD-10 for current healthcare encounters, it remains a recognized reference code for CMS Section 111 reporting, legacy claims adjudication, and historical clinical data analysis.