1A33

ICD-11 MMS 2026-01

Cystoisosporiasis

Description

A disease caused by the protozoan parasite Cystoisospora belli. This disease is characterised by watery diarrhoea, fever, abdominal pain, nausea, or malaise. Transmission is by the faecal-oral route, commonly through the ingestion of contaminated food or water. Confirmation is by identification of Cystoisospora belli in a faecal sample.

Exclusions from above levels

  • NE83.1 – Infection arising from device, implant or graft, not elsewhere classified

Child codes

  • 1A33.0 – Cystoisosporiasis of small intestine
  • 1A33.1 – Cystoisosporiasis of colon
  • 1A33.Y – Other specified cystoisosporiasis
  • 1A33.Z – Cystoisosporiasis, unspecified

Sibling codes

  • 1A30 – Infections due to Balantidium coli
  • 1A31 – Giardiasis
  • 1A32 – Cryptosporidiosis
  • 1A34 – Sarcocystosis
  • 1A35 – Blastocystosis
  • 1A36 – Amoebiasis
  • 1A3Y – Other specified protozoal intestinal infections
  • 1A3Z – Protozoal intestinal infections, unspecified

Foundation entity

Cystoisosporiasis – http://id.who.int/icd/entity/137713224

Allowed postcoordination axes

Part of: 01: Certain infectious or parasitic diseases