Tick-borne viral encephalitis, unspecified

This code signifies an acute inflammatory condition of the brain caused by a viral infection transmitted by ticks, where the specific type of tick-borne encephalitis virus is not identified. It represents a serious neurological infection that can lead to significant morbidity and, in some cases, mortality.

Use this code when documentation confirms a diagnosis of viral encephalitis and explicitly states a tick bite as the likely source of infection, but the specific viral agent (e.g., Powassan virus, European tick-borne encephalitis virus) is not specified. This code is appropriate when laboratory testing for specific tick-borne encephalitis viruses is pending or inconclusive, or when the clinician has not documented a more precise diagnosis.

• Do not use this code if the specific type of tick-borne encephalitis virus is identified; instead, code to the more specific diagnosis.
• Ensure documentation clearly links the encephalitis to a tick bite; otherwise, consider codes for other forms of viral encephalitis.
• Always review for any associated neurological sequelae that may require additional coding.