A83 Mosquito-borne viral encephalitis

The ICD-10-CM code for Mosquito-borne viral encephalitis is A83 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Chapter

1: Certain infectious and parasitic diseases (A00-B99)

Section

A80-A89: Viral and prion infections of the central nervous system (A80-A89)

Category A83

10 codes (9 billable)

FY2026 Status

Stable since FY2024

Official Coding Guidelines

HIV Infections (TOC entry)

a. Human Immunodeficiency Virus (HIV) Infections .............................................................. 19

Infectious agents causing diseases in other chapters (TOC)

b. Infectious agents as the cause of diseases classified to other chapters ................................. 22

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool