ICD-10-CM 2027
ICD-10 code for Aphthous fever
Other specified viral infections characterized by skin and mucous membrane lesions
From the official ICD-10-CM alphabetic index entry “Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › aphthous”. Page updated September 29, 2026.
About coding Aphthous fever
The ICD-10-CM code for Aphthous fever is B08.8 (Other specified viral infections characterized by skin and mucous membrane lesions).
Within B08, choose B08.8 (Other specified viral infections characterized by skin and mucous membrane lesions) only when documentation doesn't support a more specific option: other orthopoxvirus infections (B08.0), Molluscum contagiosum (B08.1), exanthema subitum [sixth disease] (B08.2), erythema infectiosum [fifth disease] (B08.3), enteroviral vesicular stomatitis with exanthem (B08.4), enteroviral vesicular pharyngitis (B08.5), parapoxvirus infections (B08.6) and yatapoxvirus infections (B08.7).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 865 (Viral Illness with MCC, relative weight 1.3485) and DRG 866 (Viral Illness without MCC, relative weight 0.8692), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Aphthous fever ICD-10 codes
What is the ICD-10 code for Aphthous fever?
- B08.8 — Other specified viral infections characterized by skin and mucous membrane lesions.
Is B08.8 billable?
- Yes. B08.8 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B08.8 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B08.8 as a principal diagnosis.
Is B08.8 a CC or MCC?
- No. B08.8 is neither a CC nor an MCC under MS-DRG v44.0.