International travel and health



Caused by Angiostrongylus cantonensis, a nematode parasite.


Transmission occurs by ingestion of third-stage larvae in raw or undercooked snails or slugs. It can also result from ingestion of raw or undercooked transport hosts such as freshwater shrimp or prawns, crabs and frogs.

Nature of the disease

Ingested larvae can migrate to the central nervous system and cause eosinophilic meningitis.

Geographical distribution

Occurs predominantly in Asia and the Pacific, but has also been reported in the Caribbean. Geographical expansion may be facilitated by infected ship-borne rats and the diversity of snail species that can serve as intermediate hosts.


Food and water hygiene (Chapter 3); in particular avoid eating raw/undercooked snails and slugs, or raw produce such as lettuce. No vaccine is available.