Tick-borne viral encephalitis, unspecified

This code signifies an inflammation 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 neurological condition characterized by symptoms such as fever, headache, altered mental status, and potential seizures, resulting from viral invasion of the central nervous system.

Use this code when documentation confirms a diagnosis of tick-borne viral encephalitis, but the medical record does not specify the particular viral agent (e.g., European, Far Eastern, or Powassan virus). This code is appropriate when the physician explicitly states "unspecified tick-borne viral encephalitis" or similar language indicating the lack of viral specificity.

• Avoid using this code if a more specific type of tick-borne viral encephalitis is documented (e.g., A84.0 for Far Eastern tick-borne encephalitis).
• Ensure the documentation clearly links the encephalitis to a tick bite or exposure, even if the specific virus is unknown.
• Consider sequencing this code as the primary diagnosis if it is the reason for the encounter, followed by codes for any associated neurological manifestations.