A81Atypical virus infections of central nervous system
Code usage status
Primary diagnosis
Select a more specific code
Apply only when it matches the confirmed diagnosis and the documented clinical record.
Specificity
Do not use A81 directly
Use the most specific code supported by the record.
- Group A80-A89
- Viral infections of the central nervous system
- Official Vietnamese name
- Bệnh do virus không điển hình ở hệ thần kinh trung ương
- Additional WHO coding guidance
- Incl.: prion diseases of the central nervous system
Related A81 codes
A81.0
Primary diagnosis candidate
Creutzfeldt-Jakob disease
A81.1
Primary diagnosis candidate
Subacute sclerosing panencephalitis
A81.2
Primary diagnosis candidate
Progressive multifocal leukoencephalopat hy
A81.8
Primary diagnosis candidate
Other atypical virus infections of central nervous system
A81.9
Primary diagnosis candidate
Atypical virus infection of central nervous system, unspecified
Clinical record checklist
View coding guide →- Confirm that the code matches the final documented diagnosis.
- Use one primary-diagnosis code and record only relevant additional conditions.
- Review Ministry indicators, inclusions, exclusions and notes.
- Do not infer a diagnosis beyond the clinical record.
2026 regulatory basis
Indicators are taken from columns 24–29 of the classification accompanying Circular 06/2026/TT-BYT, cross-referenced with Decision 1849/QĐ-BYT and Official Dispatch 4059/BYT-BH.
