Ten people in Wales have been diagnosed with cyclospora, a parasite that can cause explosive diarrhoea, prompting a health warning for travellers.
Rise in cases across the UK
Public Health Wales has identified a sharp increase in cyclospora infections among Welsh travellers returning from Mexico. Between April 30 and July 15 2026, 67 cases were reported across the UK, including 10 in Wales, 30 in England, and 27 in Scotland.
The infection is contracted by drinking unclean water or eating contaminated food that has not been cooked thoroughly or washed with clean water. Common sources include herbs, salad, and soft fruit.
Symptoms and advice
Symptoms include frequent watery diarrhoea, abdominal cramping, bloating, nausea, flatulence, low-grade fever, loss of appetite, and weight loss. The illness is usually mild, but can be more serious in immunocompromised individuals, who may need antibiotics.
The UK Health Security Agency (UKHSA) advises travellers to Mexico and other affected areas to drink bottled water, eat thoroughly cooked food, and avoid fresh uncooked berries, herbs, unpeeled fruit, and salad items, even in high-end resorts.
Travel links and deaths
Among UK cases, 48 reported travel to Mexico, with some staying in the Riviera Maya and Cancún regions. One person travelled to the USA alone, one to the USA and Mexico, and one to Kenya. UKHSA anticipates further cases linked to summer travel to Mexico and the USA, where a widespread outbreak has occurred.
Two deaths have been reported in Michigan, according to the Michigan Department of Health and Human Services, both involving individuals with underlying health conditions.
A Public Health Wales spokesperson said: "Cyclospora is a parasite not found in the UK, which can cause gastrointestinal illness in people who are affected, including frequent, watery diarrhoea, abdominal cramps and fever."
They added that travellers should maintain stringent food and water hygiene, and contact NHS 111 Wales or their GP if symptoms persist after three days.
