Contagious diarrhoea bug found in popular UK supermarket product

A highly infectious bug causing vomiting and diarrhoea has been found in nearly a fifth of pre-washed vegetables sold in UK supermarkets. Scientists took samples from various supermarkets across Kent and discovered that almost one in five - 17 percent - were contaminated with cryptosporidium.

This is the same parasite that caused an outbreak in Devon in May, affecting over 100 people. The incident in the Brixham area was linked to a faulty air valve, resulting in contaminated tap water.

Now, research carried out by the University of Kent School of Biosciences has found the parasite in several packs of ready-to-eat vegetables, reports the Express.

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This discovery has led to warnings about how customers should handle such produce before eating it.

The research team did not reveal which supermarkets sold the contaminated produce but suggested that similar figures are likely across the entire sector.

They stressed that pre-washed or ready-to-eat vegetables should be handled with caution.

Experts analysed 36 packs of pre-washed vegetables bought from four supermarkets in Canterbury, Kent, between May and July 2023. The samples were randomly chosen, and duplicates of each variety were tested.

The findings showed that 12 samples didn't meet the inclusion criteria. From the remaining 24, 58 percent tested positive for cryptosporidium, and 17 percent (four samples) bore similarities to cryptosporidium parvum, a primary cause of human cryptosporidiosis.

The researchers pointed out that the source of contamination was uncertain but could have happened at any point from farm to shop.

They highlighted the potential public health implications in the UK and urged for more investigations.

As per the report, pre-washed and ready-to-eat vegetables are usually washed more thoroughly with water containing chlorine disinfectants compared to unpackaged vegetables.

These vegetables are expected to be parasite-free and safe to eat directly from the packaging.

However, cryptosporidium oocysts are resistant to chlorine disinfection and can only be reliably removed by boiling water or filtration, posing a risk of illness if not properly treated.

In their report, the experts stated: "This pilot study could unlock a potential common source of cryptosporidium infection across the various regions in the UK. The vegetables from individual chain supermarkets are packaged in their own central facilities and subsequently distributed nationwide."

"Our study could contribute to developing better strategies to prevent infection with Cryptosporidium. Further studies could focus on tracking the exact point of contamination and addressing it."