ICD-10-CM › A00-B99 › A80-A89 › A84 Tick-borne viral encephalitis › A84.9
Tick-borne viral encephalitis, unspecified
ValidICD-10-CM diagnosis code.
Valid for claims with a date of service in the current code year.
What has happened to this code
Every change the publisher made, from 2007 to now. Entries marked draft are from the pre-implementation releases: ICD-10 took effect on 1 October 2015, so nothing before FY2016 was ever valid on a claim.
- FY2007 Added to the draft code set draft Tick-borne viral encephalitis, unspecified
Official coding rules
Published by CDC for FY2027. A rule attached to a category binds every code beneath it, so the rules inherited from this code's ancestors are shown with the code they come from.
Inherited from A84 Tick-borne viral encephalitis
Includes
- tick-borne viral meningoencephalitis
Inherited from the A80-A89 section Viral and prion infections of the central nervous system (A80-A89)
Excludes1 - never coded here
- postpolio syndrome (G14)
- sequelae of poliomyelitis (B91)
- sequelae of viral encephalitis (B94.1)
How CDC's index refers to this code
Wording from the official alphabetic index. Much of it appears nowhere in the code description, which is why a search for the everyday phrase so often finds nothing.
- Myelitis
- Phrenitis
- Cephalitis
- Cerebritis
- Ependymitis
- Cerebellitis
- Fever > brain
- Ventriculitis
- Febris, febrile
- Meningomyelitis
- Mesencephalitis
- Myelomeningitis
- Parencephalitis
- Syringomyelitis
- Fever > cerebral
- Radiculomyelitis
- Encephalomyelitis
- Meningocerebritis
- Myeloencephalitis
- Encephalomeningitis
- Meningoencephalitis
- Encephalitis > acute
- Meningomyeloneuritis
- Encephalomeningomyelitis
- Encephalomyelomeningitis
- Meningoencephalomyelitis
- Poliomeningoencephalitis
- Virus, viral > infection
- Fever > viral hemorrhagic
- Myelopathy > in > infection
- Disease, diseased > cerebral
- Meningoencephalitis > acute NEC
- Infection, infected, infective > brain
- Disease, diseased > brain > inflammatory
- Disease, diseased > cerebellar, cerebellum
- Inflammation, inflamed, inflammatory > brain
- Inflammation, inflamed, inflammatory > cerebral
- Infection, infected, infective > spinal cord NOS
- Inflammation, inflamed, inflammatory > spinal > cord
- Encephalitis > tick-borne
Showing 40 of 42 index phrases.
Codes in the same group
| Code | Description | Status |
|---|---|---|
| A84.0 | Far Eastern tick-borne encephalitis [Russian spring-summer encephalitis] | Valid |
| A84.1 | Central European tick-borne encephalitis | Valid |
| A84.8 | Other tick-borne viral encephalitis | Not billable |