U12.9COVID-19 vaccines causing adverse effects in therapeutic use, unspecified
Code usage status
Primary diagnosis
May be used as the primary diagnosis
Apply only when it matches the confirmed diagnosis and the documented clinical record.
Specificity
Complete code in the classification
Use when the diagnosis matches and no exclusion applies.
- Chapter XXII
- Codes for special purposes
- Official Vietnamese name
- Vắc xin COVID-19 gây tác dụng bất lợi trong điều trị, không xác định
- Additional WHO coding guidance
- Note: This code is to be used as an external cause code (i.e. as a sub category under Y59, "Other and unspecified vaccines and biological substances"). In addition to this, a code from another chapter of the classification should be used indicating the nature of the adverse effect. Correct administration of COVID-19 vaccine in prophylactic therapeutic use as the cause of any adverse effect.
Related U12 codes
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.
