A83.8 — Other mosquito-borne viral encephalitis
A83.8 is a billable, specific ICD-10-CM code for other mosquito-borne viral encephalitis. It is valid for submission on a claim.
Risk adjustment
A83.8 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
A83.8 is named in 5 Medicare coverage policies — 5 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56612Billing and Coding: CT of the Head
- A56771Billing and Coding: Special Electroencephalography
- A56773Billing and Coding: Neurophysiology Evoked Potentials (NEPs)
- A57204Billing and Coding: MRI and CT Scans of the Head and Neck
How A83.8 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to A83.8.
- Encephalitis›Ilheus(virus)
- Encephalitis›viral, virus›arthropod-borne NEC›mosquito-borne›specified NEC
Related codes at this level
Codes that share A83. If A83.8 is not quite right, the correct code is usually one of these.
Questions about A83.8
- Is A83.8 a billable ICD-10-CM code?
- Yes. A83.8 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does A83.8 sit in the tabular list?
- Certain infectious and parasitic diseases (A00-B99), in the block Viral and prion infections of the central nervous system (A80-A89).