B94.1
Sequelae of viral encephalitis
B94.1 (also written B941) is a billable ICD-10-CM diagnosis code for sequelae of viral encephalitis. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 5 codes in category B94 (Sequelae of other and unspecified infectious and parasitic diseases). The Alphabetic Index lists it under 2 entries. Its coding notes include a Code first instruction, a Use additional code instruction and 5 Excludes2 entries.
Code first
If the underlying condition listed here is present and known, sequence it first.
Also from chapter/block level (1 note)
- condition resulting from (sequela) the infectious or parasitic disease
Use additional code
Add the listed code as a secondary code, if known.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (5 notes)
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
IRF 60% Rule
On the CMS list of diagnoses used to determine presumptive compliance with the IRF 60 percent rule.
Source: CMS IRF Presumptive Compliance-3, FY 2027 IRF PPS final rule files, effective for discharges on or after October 1, 2026Includes
Further defines or gives examples of the content of the category.
Also from chapter/block level (1 note)
- diseases generally recognized as communicable or transmissible
Notes
Also from chapter/block level (1 note)
- Categories B90-B94 are to be used to indicate conditions in categories A00-B89 as the cause of sequelae, which are themselves classified elsewhere. The 'sequelae' include conditions specified as such; they also include residuals of diseases classifiable to the above categories if there is evidence that the disease itself is no longer present. Codes from these categories are not to be used for chronic infections. Code chronic current infections to active infectious disease as appropriate.
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 2 entries