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A05.9

Billable

Bacterial foodborne intoxication, unspecified

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

Is A05.9 an HCC code?

No. A05.9 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.

This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).

What This Code Means

A05.9 is the ICD-10-CM diagnosis code for bacterial foodborne intoxication, unspecified. This code describes a bacterial infection acquired from contaminated food where the specific type of bacteria causing the illness is not identified or documented. It represents foodborne illness caused by bacterial toxins or organisms that were present in food. A05.9 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering intestinal infectious diseases (a00-a09).

A05.9 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Use this code only when the specific bacterial organism (such as Salmonella, Staphylococcus aureus, or Clostridium) cannot be determined from the medical record or test results.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for A05.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • Use this code only when the specific bacterial organism (such as Salmonella, Staphylococcus aureus, or Clostridium) cannot be determined from the medical record or test results
  • If the specific bacterial pathogen is identified, use the more specific A05 subcodes (A05.0-A05.8) instead of the unspecified code A05.9

Code Hierarchy

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