Other viral diseases, not elsewhere classified (B33) ICD-10-CM
The B33 code range covers other viral diseases, not elsewhere classified with 12 ICD-10-CM diagnosis codes. 10 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the B33 Range 12 codes · 10 billable
- B33 Other viral diseases, not elsewhere classifiedNon-billable
- B33.0 Epidemic myalgia
- B33.1 Ross River disease
- B33.2 Viral carditisNon-billable
- B33.20 Viral carditis, unspecified
- B33.21 Viral endocarditis
- B33.22 Viral myocarditis
- B33.23 Viral pericarditis
- B33.24 Viral cardiomyopathy
- B33.3 Retrovirus infections, not elsewhere classified
- B33.4 Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS]
- B33.8 Other specified viral diseases
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the B33 range.
Pleurodynia, Epidemic
An acute, febrile, infectious disease generally occurring in epidemics. It is usually caused by coxsackieviruses B and sometimes by coxsackieviruses A; echoviruses; or other enteroviruses.
Pseudorabies
A highly contagious herpesvirus infection affecting the central nervous system of swine, cattle, dogs, cats, rats, and other animals.
Retroviridae Infections
Virus diseases caused by the RETROVIRIDAE.
Viral Endocarditis
Endocarditis caused by a viral infection.
Viral Myocarditis
Myocarditis that is caused by an infection with a viral agent.
Viral Pericarditis
Pericarditis that is caused by an infection with a viral agent.
About the B33 Code Range
These viral conditions include epidemic myalgia, or muscle pain during an outbreak, Ross River disease, viral heart conditions, retrovirus infections, and hantavirus (cardio)-pulmonary syndrome.
The subdivisions separate B33.0 for epidemic myalgia, B33.1 for Ross River disease, and B33.2 for viral heart conditions. They also identify retrovirus infections in B33.3, hantavirus (cardio)-pulmonary syndrome in B33.4, and other specified viral diseases in B33.8.
Within viral heart conditions, B33.20 is unspecified. The remaining subdivisions distinguish conditions of the heart’s inner lining, muscle, surrounding sac, or heart muscle: B33.21, B33.22, B33.23, and B33.24, respectively.
Questions About This Page
How many billable codes are in the B33 range?
Of the 12 codes in this range, 10 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the B33 range classify?
The range classifies other viral diseases, not elsewhere classified. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
