A85.2 ICD-10-CM Code: Arthropod-borne viral encephalitis, unspecified

A85.2 is the ICD-10-CM diagnosis code for arthropod-borne viral encephalitis, unspecified. This code describes inflammation of the brain caused by a virus transmitted through insect bites (such as mosquitoes or ticks), when the specific type of virus has not been identified. It represents a serious infection affecting brain tissue that requires medical attention. A85.2 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering viral and prion infections of the central nervous system (a80-a89).

A85.2 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Use this code only when the specific arthropod-borne virus (such as West Nile virus, dengue, or Zika) cannot be determined; if the specific virus is identified, use a more specific A85 subcategory code instead.