ICD-10 code for West Nile fever virus

The ICD-10-CM code for West Nile fever virus is A92.30 (West Nile virus infection, unspecified). The official index lists 7 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on A92.30.

Within A92.3, choose A92.30 (unspecified) only when documentation doesn't support a more specific option: with encephalitis (A92.31), with other neurologic manifestation (A92.32) and with other complications (A92.39).

As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" 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 865 (Viral Illness with MCC, relative weight 1.3485) and DRG 866 (Viral Illness without MCC, relative weight 0.8692), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.