UK health officials have issued a warning about Cyclospora, a parasitic infection that can be contracted by eating contaminated fruit, lettuce, green salads, and herbs while on holiday. The Travel Health Pro website, backed by the Foreign Office, highlighted that most UK cases are linked to travel to Mexico, while the United States is currently experiencing a large outbreak.
Outbreak details and affected regions
The infection, which spreads through contaminated water or food, has reached 34 US states and infected nearly 7,000 people, according to the US Centers for Disease Control and Prevention (CDC). The main symptom is frequent, watery diarrhoea. Cyclospora is also found in Central and South America, South and Southeast Asia, the Middle East, and Africa. As of July 2026, a multistate US outbreak has been linked to shredded iceberg lettuce from central Mexico.
Travel Health Pro stated: “People usually become infected by eating or drinking food or water contaminated with human faeces. Foods most commonly linked to Cyclospora include fresh produce such as soft or unpeeled fruit, lettuce, green salads and herbs like coriander or basil. You cannot catch Cyclospora from close contact with someone who has the infection.”
Symptoms and risks
Symptoms typically appear about a week after consuming contaminated food or drinks and include watery diarrhoea, fever, stomach cramps, loss of appetite, weight loss, tiredness, muscle pain, bloating, excess wind, and feeling sick. Infections are usually mild and resolve on their own, but symptoms can last for several weeks and may return. People with weakened immune systems, including those with HIV, are at greater risk of severe illness.
Prevention advice
To reduce risk, travellers should follow good food and water hygiene, even in luxury hotels: wash hands regularly with soap and clean water; use alcohol hand gel only when handwashing is not possible; drink only bottled or boiled tap water where water supply is unsafe; avoid ice in drinks; avoid fresh produce that may not have been washed with safe water, including berries, salads, vegetables, and herbs; choose fruit that can be peeled, such as bananas and oranges; opt for pasteurised dairy products; eat freshly cooked food served hot; and be aware that smoothies, juices, and other drinks may contain raw fruit, herbs, or vegetables.
What to do if ill abroad
If you become ill abroad, drink plenty of safe fluids like bottled or boiled water, use oral rehydration solutions to prevent dehydration, seek early medical advice if you have a weakened immune system, and get medical help for severe or persistent symptoms.
Pharmacist's perspective
Karen Hutchinson, Prescribing Pharmacist at Chemist4U, explained: “Cyclospora cayetanesis is a parasite that infects the small intestine and causes an illness known as cyclosporiasis. The parasite is commonly found in certain parts of Central and South America, southeast Asia, the Middle East and Africa. ... In recent days though, it has attracted attention due to a significant rise in infections in the US, with 1,645 confirmed cases, leaving many wondering how this could impact people in the UK. ... You can contract cyclospora through a number of sources, mainly by drinking unclean water or eating food that has been contaminated or not properly cooked and washed. ... Common symptoms ... include watery diarrhoea, stomach cramps, nausea and fatigue while some people may also experience a fever or even vomiting. Without treatment, these symptoms can persist for several weeks, if not longer. Most people who have a healthy immune system will recover without treatment. However, if you have a weakened immune system then you will be more vulnerable and should seek medical advice as symptoms may last longer.”
