Health officials in the United Kingdom are warning of a rise in Cyclospora cayetanensis infections among travellers returning from Mexico.

This trend is significant because the parasite causes severe gastrointestinal distress and highlights the risks of consuming contaminated food and water in endemic regions.

Since April 2024, the UK has recorded 67 cases of the infection [1]. The parasite is transmitted when people ingest contaminated food or water, a common occurrence for those visiting regions where the parasite is prevalent, such as Mexico [1], [3].

Patients typically experience what is described as explosive diarrhoea [2], [3]. This symptom is often accompanied by other signs of severe gastrointestinal illness. Because the infection is linked to specific travel patterns, health authorities are monitoring those returning from abroad to identify new clusters.

While the UK case count remains relatively low, other regions have seen a much larger surge. In the U.S., there have been 6,707 laboratory-confirmed cases of Cyclospora since May 1, 2024 [4]. These cases have been reported across 45 states [4].

The discrepancy in numbers between the UK and the U.S. may reflect different levels of exposure or variations in laboratory testing and reporting protocols. However, both sets of data indicate a broader trend of parasite transmission associated with international travel and food supply chains.

Health experts said travellers should exercise caution with water and produce in endemic areas to prevent ingestion of the parasite [1], [3].

“67 cases [of Cyclospora] recorded [in the UK] since April 2024”

The rise in Cyclospora cases in both the UK and the U.S. suggests a widespread public health challenge related to global travel and food safety. Because the parasite is often linked to imported produce or contaminated water in specific geographic hubs like Mexico, the current outbreak underscores the difficulty of containing food-borne illnesses in an interconnected global economy.