UK holidaymakers are facing a significant health alert due to a rise in cases of cyclosporiasis, a parasitic infection known for causing severe gastrointestinal distress. The UK Health Security Agency (UKHSA) has reported a total of 67 cases since April 2026, predominantly among individuals who have recently returned from Mexico. This surge in infections coincides with a widespread outbreak in the United States, where over 18,000 cases have been documented across 45 states, although the precise source of the outbreak remains unidentified.
Understanding Cyclosporiasis
Cyclosporiasis is attributed to the cyclospora parasite, which can contaminate various food items, including salads, herbs, and soft fruits. Notably, this parasite is not endemic to the UK, meaning that the risk of person-to-person transmission is negligible, according to health experts. The recent UK cases have predominantly emerged from travellers returning from Mexico’s popular tourist destinations, including the Riviera Maya and Cancún, where many reported dining at all-inclusive resorts.
From 30 April to 15 July 2026, the UKHSA noted that 30 cases were identified in England, 27 in Scotland, and 10 in Wales. Alarmingly, of the 52 cases for which travel details were available, 48 had visited Mexico, highlighting a direct correlation between travel to this region and the subsequent development of the illness.
Symptoms and Severity
The symptoms of cyclosporiasis can be debilitating. Patients often experience frequent and explosive watery diarrhoea, with some reporting the need to use the toilet as many as 20 times daily. One affected individual, Nick Palmiter from Monroe County, Michigan, described the sensation as feeling “like you have a balloon in your stomach,” indicative of the intense pressure and discomfort associated with the illness.
While most infections resolve without medical intervention, cases that persist or become severe may require antibiotic treatment. The UKHSA anticipates that the number of infections may rise with the onset of summer travel, particularly to Mexico and potentially the US.
Preventative Measures for Travellers
In light of this outbreak, health authorities are urging travellers to adopt stringent food and water hygiene practices while abroad. Recommendations include drinking bottled water and ensuring that all food is thoroughly cooked, even in high-end all-inclusive settings. Travellers are also advised to avoid consuming fresh produce items such as uncooked berries, unpeeled fruits, and salads, which may increase their risk of infection.
Dr Philip Veal from the UKHSA emphasised the importance of recognising symptoms that may arise after travel, including watery diarrhoea, stomach cramps, and flu-like symptoms. He urged anyone experiencing these issues to seek medical attention promptly and to inform healthcare providers of their recent travel history.
Why it Matters
The rising incidence of cyclosporiasis among UK travellers underscores the critical need for heightened awareness and preventive measures in the face of global travel. As the summer holiday season approaches, understanding the risks associated with certain destinations can help mitigate the spread of this distressing infection, safeguarding the health of travellers and the broader public. With ongoing investigations and monitoring by health authorities, the imperative remains for individuals to remain vigilant and proactive in their health practices while abroad.