Travellers to Mexico warned over increase in gastro illness cases

UK health authorities say they are liaising with Abta and their Mexican counterparts over an increase in cyclospora infections which can cause severe gastrointestinal illness and diarrhoea.

A statement from the UK Health Security Agency (UKHSA), Public Health Scotland and Public Health Wales said 67 cases were reported between April 30 and July 15, with 48 of 52 cases where travel information was known having visited Mexico and one both Mexico and the US.

Affected individuals primarily reported travel to the Riviera Maya region, with several reporting travel to Cancun.

The statement said seasonal outbreaks of cyclosporiasis in UK travellers returning from Mexico have been reported since 2015, with the highest annual total of 359 cases reported in 2016 and an annual average of 93 cases between 2022 and 2025.

It added: “UKHSA is anticipating a continued rise in reported travel-associated cases linked to increased summer travel to Mexico and to the USA, where there has been a widespread outbreak reported.”

Cyclospora cayetanensis is a parasite that does not naturally occur in the UK and cyclospora infection is transmitted through consumption of food or drink that is contaminated with infected human faeces.

Infection can cause “frequent, watery diarrhoea, abdominal cramping, bloating, nausea, flatulence, low-grade fever, loss of appetite and weight”, though most cases resolve on their own.

The statement said: “Travellers are advised to maintain good food and water hygiene at all times, even if staying in high-end all-inclusive resorts.

“If possible, travellers should choose freshly prepared food that is thoroughly cooked and served piping hot. Certain foods should be avoided, such as fresh uncooked berries and herbs, unpeeled fruit and salad items.”

It added: “UKHSA is liaising with Abta and Mexican public health authorities to inform investigations of these clusters.”

Dr Philip Veal, consultant in travel health at UKHSA, said: “We have recently detected a rise in Cyclospora infections among travellers returning from Mexico. These infections are caused by a parasite and can affect the stomach and intestines.

“Travellers to Mexico and other areas where the infection is more common can reduce their risk by following good food and water hygiene measures, including drinking bottled water and eating thoroughly cooked food, even when staying in high-end all-inclusive resorts. We also advise avoiding certain foods such as fresh uncooked berries and herbs, unpeeled fruit and salad items.

“If you develop symptoms after returning from travel, such as watery diarrhoea, loss of appetite, weight loss, stomach cramps or pain, bloating, increased wind, nausea, fatigue or other flu-like symptoms, please seek medical attention and inform your healthcare professional of your travel history.”