UK tourists travelling to Mexico have been warned about a sharp rise in infections caused by a microscopic parasite that can trigger severe gastrointestinal symptoms, including frequent or 'explosive' diarrhoea.
The UK Health Security Agency (UKHSA) recorded 67 cases of cyclosporiasis across England, Scotland and Wales between 30 April and 15 July 2026. Among the 52 patients whose travel history was available, 48 had recently visited Mexico.
