The United States Food and Drug Administration (FDA) has launched an investigation into a cyclospora outbreak that has so far sickened 72 individuals across multiple states. The agency confirmed on 21 July 2026 that it is working with the Centres for Disease Control and Prevention (CDC) and state partners to identify the source of the parasite, which typically causes watery diarrhoea, cramping, and fatigue that can last weeks if untreated.
No specific food product or distribution chain has been linked to the cases, making the investigation particularly challenging. Cyclospora cayetanensis is a microscopic parasite that is not transmitted directly from person to person; infections occur when people ingest food or water contaminated with the organism. Outbreaks in the US are frequently traced to imported fresh produce such as basil, cilantro, raspberries, and salad mixes from tropical and subtropical regions.
The UK Health Security Agency (UKHSA) has not issued a formal alert but is understood to be monitoring the situation for any cases that may arise in travellers returning from the United States. Cyclospora infections are relatively rare in the UK, with most cases linked to foreign travel. However, the UK imports significant volumes of fresh fruit and vegetables from North America and other regions, meaning contaminated shipments could theoretically reach British supermarkets.
Public health experts caution that the incubation period for cyclospora is typically about one week, and symptoms can reappear after a period of improvement. Diagnosis requires specific stool tests that are not routinely performed unless a doctor suspects the parasite. The FDA has urged clinicians to consider cyclospora in patients with prolonged diarrhoea who have recently consumed imported produce or travelled abroad.
The investigation underscores ongoing vulnerabilities in global food supply chains. For UK consumers, the main risk remains travel-related, but importers and retailers are advised to review their supply chain hygiene practices. The FDA will continue to update its investigation as new information emerges, and the UK Food Standards Agency (FSA) is expected to issue guidance if any implicated products are found to have reached British shores.