A84.89 ICD-10-CM Code: Other tick-borne viral encephalitis

A84.89 is the ICD-10-CM diagnosis code for other tick-borne viral encephalitis. This code describes inflammation of the brain caused by a virus transmitted through tick bites, excluding the more common types like Lyme disease. It represents less frequently encountered tick-borne viral infections that affect the brain and nervous system. A84.89 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).

A84.89 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.

Verify the specific tick-borne virus identified in the clinical documentation, as some may have more specific ICD-10-CM codes available; use this code only when the specific virus is not classifiable elsewhere.