B33.4Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS]

B33.4 is the ICD-10-CM diagnosis code for Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS]. It belongs to category B33 (other viral diseases, not elsewhere classified), block B25-B34 (other viral diseases) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within B33 (other viral diseases, not elsewhere classified), B33.4 is specifically for Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS]. Related codes cover epidemic myalgia (B33.0), Ross River disease (B33.1), viral carditis (B33.2), retrovirus infections, not elsewhere classified (B33.3) and other specified viral diseases (B33.8).

Don't report B33.4 together with the conditions in its Excludes1 note: hantavirus disease with renal manifestations (A98.5) and hemorrhagic fever with renal manifestations (A98.5).

Use an additional code to identify any associated acute kidney failure (N17.9).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

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.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 079.81 (Hantavirus infection).