B50.9 — Plasmodium falciparum malaria, unspecified
B50.9 is a billable, specific ICD-10-CM code for plasmodium falciparum malaria, unspecified. It is valid for submission on a claim.
Other codes that can never be billed with B50.9
These codes carry an Excludes1 note pointing at B50.9. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading B50.9 alone.
Risk adjustment
B50.9 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
B50.9 is named in 3 Medicare coverage policies — 3 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A57060Billing and Coding: Visual Electrophysiology Testing
- A57599Billing and Coding: Visual Electrophysiology Testing
- A58706Billing and Coding: Electroretinography (ERG)
How B50.9 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to B50.9.
- Chagres fever
- Estivo-autumnal malaria(fever)
- Fever›Chagres
- Fever›continued malarial
- Fever›estivo-autumnal(malarial)
- Fever›Panama(malarial)
- Fever›subtertian
- Malaria, malarial›algid
- Malaria, malarial›continued(fever)
- Malaria, malarial›estivo-autumnal
- Malaria, malarial›falciparum
- Malaria, malarial›tropical
Code history
B50.9 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.
Related codes at this level
Codes that share B50. If B50.9 is not quite right, the correct code is usually one of these.
Questions about B50.9
- Is B50.9 a billable ICD-10-CM code?
- Yes. B50.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does B50.9 sit in the tabular list?
- Certain infectious and parasitic diseases (A00-B99), in the block Protozoal diseases (B50-B64).