A85.2 Arthropod-borne viral encephalitis, unspecified

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Excludes1 (never code together)

• West nile virus with encephalitis (A92.31)

Applies from A85 Other viral encephalitis, not elsewhere classified

Includes

• specified viral encephalomyelitis NEC
• specified viral meningoencephalitis NEC

Excludes1 (never code together)

• encephalitis due to cytomegalovirus (B25.8)
• encephalitis due to herpesvirus NEC (B10.0-)
• encephalitis due to herpesvirus [herpes simplex] (B00.4)
• encephalitis due to measles virus (B05.0)
• encephalitis due to mumps virus (B26.2)
• encephalitis due to poliomyelitis virus (A80.-)
• encephalitis due to zoster (B02.0)
• lymphocytic choriomeningitis (A87.2)
• myalgic encephalomyelitis (G93.32)

MS-DRG index

Defines the logic of DRG(s) 023-024 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 064 Viral encephalitis transmitted by other and unspecified arthropods

Diagnosis Index entries for A85.2

• Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) › arboviral, arbovirus NEC
• Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) › arthropod-borne NEC (viral)
• Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) › viral, virus › arthropod-borne NEC

Nearby codes

• A85 Other viral encephalitis, not elsewhere classified
• A85.0 Enteroviral encephalitis
• A85.1 Adenoviral encephalitis
• A85.2 Arthropod-borne viral encephalitis, unspecified (this code)
• A85.8 Other specified viral encephalitis