Health investigators in France have linked raw goat's milk cheese and pre-packaged lettuce to outbreaks of a severe parasite infection after cases surged eight-fold across the country last year.
Officials launched an investigation when infections of Cryptosporidium parvum rose to 166 between January and September last year, compared to fewer than 20 cases during the same period in previous tracking. Scientists later established that 76 of those infections belonged to two major outbreaks.
The first French outbreak affected 45 people who fell ill between April and June last year. Health investigators identified raw goat's milk cheese as the suspected source after interviewing 23 patients, 17 of whom reported eating the product.
Investigators traced the cheese back to two dairy farms that supplied the milk. Although both farms denied having cryptosporidiosis in their herds, officials were unable to test batches of the cheese because none remained available. Currently, Europe has no regulations requiring food to be tested for Cryptosporidium.
Investigating the French outbreaks
The second outbreak involved 31 people who became ill between June and July last year, including one patient who required hospitalisation. Investigators linked the spread to pre-packaged lamb's lettuce after 19 patients reported purchasing various brands of the salad leaf at different supermarkets.
Store shopping records pointed to a shared supply chain, with several purchases tied to a single distributor. However, no lettuce was available for laboratory testing. Despite the lack of physical proof, health officials suspect both the goat's cheese and the lettuce caused the outbreaks.
The findings follow a major water contamination event two years ago in Brixham, Devon, where Cryptosporidium was discovered in local drinking water supplies.
That UK contamination event lasted over 54 days and left more than 140 people suffering from sickness and diarrhoea. South West Water, the utility provider responsible for the area, was fined £2 million last month over the incident.
Contamination risks and symptoms
In England, around 4,000 people are infected with Cryptosporidium each year. The UK Health Security Agency (UKHSA) publishes safety guidance explaining how the public can protect themselves from the parasite.
According to the UKHSA, Cryptosporidium "can be found in the intestines and faeces of infected humans and animals." The parasite can pollute swimming pools, outdoor water sources, and poorly treated water systems.
In food, the bug is most commonly found in raw milk and fresh produce such as whole fruits and vegetables. It can also survive on outdoor surfaces, including farm gates, boots, and agricultural clothing.
Humans contract cryptosporidiosis by swallowing water or food contaminated by infected people or animals, or by coming into direct contact with infected stool. The disease has no effective drug treatment and causes severe, mostly watery diarrhoea that can last for weeks.
Other symptoms include stomach pains, nausea, vomiting, fever, and loss of appetite, which can lead to severe dehydration and weight loss. In extreme cases, intense diarrhoea can become life-threatening due to dangerous fluid loss.
High-risk groups and Cyclosporiasis spread
Children aged between one and five are most commonly affected by cryptosporidiosis, placing parents who change nappies at increased risk. Individuals who handle infected livestock or consume untreated water are also more vulnerable to infection.
The warning comes as health chiefs report the UK arrival of a separate parasite, Cyclospora, which caused explosive diarrhoea in tens of thousands of Americans this summer. That outbreak was linked to an iceberg lettuce farm in Mexico and resulted in two deaths and hundreds of hospitalisations in the United States in recent weeks.
Health officials warned that the debilitating Cyclospora infection, which triggers weeks of violent diarrhoea, abdominal cramps, and vomiting, has now reached the UK. At least 67 Britons have fallen ill with the illness since May.
