B99 — Other and unspecified infectious diseases
Is B99 billable?
No — B99 is a non-billable header code. B99 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 2 billable codes beneath B99.
Billable codes under this header
B99 at a glance
| Code | B99 |
|---|---|
| Description | Other and unspecified infectious diseases |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
How is B99 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to B99. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Arthropathy › postinfectious NEC
- Pneumonia › postinfectional NEC (acute) (double) (migratory) (purulent) (septic) (unresolved)
- ConjunctivitisNOS › in › infectious disease NEC (staphylococcal) (streptococcal)
- Encephalitis › in › infectious disease NEC (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute)
- Iridocyclitis › in › infectious disease NOS
- Mastoiditis › in › infectious disease NEC (coalescent) (hemorrhagic) (suppurative)
- Myopathy › in › infectious disease NEC
- Neuritis › acoustic › in › infectious disease NEC (rheumatoid)
- Otitis › externa › in › infectious disease NEC (acute)
- Polyneuropathy › in › infectious › disease NEC (peripheral)
- Palsy › cranial nerve › multiple › in › infectious disease
Use additional code — inherited from Chapter 1
Report an additional code alongside B99 to fully describe the condition. B99 is sequenced first.
- code to identify resistance to antimicrobial drugs (Z16.-)
Excludes2 — not included here — inherited from Chapter 1
The conditions below are not part of B99, but a patient may have both at the same time. When documentation supports it, B99 and the excluded code may both be reported.
- 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)
What codes fall under B99? (2)
How long has B99 existed?
B99 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.