One death and 7 HUS cases in UK E. coli outbreak

One person has died in an E. coli outbreak in the United Kingdom linked to salad leaves.

The UK Health Security Agency (UKHSA) identified two people in England who died within 28 days of being infected with the outbreak strain. Based on information from health service clinicians, only one death is likely linked to STEC infection. Both individuals had underlying medical conditions and the deaths were in May.

UKHSA also revealed the incident is a re-emergence of an STEC cluster investigated in 2023, where no source could be confirmed.

Seven HUS cases
There have been 275 confirmed patients in the Shiga toxin-producing E. coli (STEC) O145 outbreak since May 2024. All confirmed cases had symptom onset dates before June 4.

In total, 182 people are sick in England, 31 in Wales, and 58 in Scotland. Northern Ireland has four cases and likely acquired their infections in England.

Of 122 hospitalized cases, 57 percent were female and had a median age of 35, with a range of 6 to 85 years old.

Seven cases of Hemolytic Uremic Syndrome (HUS) have been associated with the outbreak. HUS is a clinical syndrome related to E. coli, which can lead to kidney failure and death. Five HUS cases live in England and two in Scotland. Six are female, and all cases range in age from 12 to 59 years old.

Of the 273 primary cases, 57 percent are female, with a median age of 30 and a range of 1 to 89. The most affected age groups were 20 to 29 and 30 to 39.

Amy Douglas, incident director at UKHSA, said: “We’re pleased that fewer cases have been reported, however we still expect to see a few more cases linked to this outbreak as further samples are referred to us for testing.”

Lettuce suspicion
Work by the Food Standards Agency (FSA) and Food Standards Scotland (FSS) led to the withdrawal and recall of various sandwiches, wraps, subs, and rolls.

The investigation indicated a higher-than-expected proportion of patients reported having pre-packaged sandwiches during the seven days before becoming unwell. Epidemiological studies showed a statistically significant association between illness and consumption of sandwiches containing lettuce.

Samworth Brothers, This! and Greencore Group recalled a range of products sold at various stores, such as Tesco, Aldi, Asda, Boots, WH Smith, Co-op, Morrisons, and Sainsbury’s.

FSA and FSS have identified one supplier of potentially contaminated lettuce but investigations are ongoing at two other lettuce suppliers at the grower stage of the supply chain.

All test results have been negative for STEC, but general or indicator E. coli was identified in sandwich and lettuce products, indicating a possible contamination event.

Regarding short shelf life and highly perishable products such as salads, microbiological confirmation of the outbreak strain in the foods implicated is difficult as they have usually already been consumed, said UKHSA.

Ready-to-eat salads can be contaminated with pathogens at the pre-harvest level via flooding, rainwater run-off, or irrigation water containing animal feces, or post-harvest during washing and packaging.

“Although we are confident in the likely source of the outbreak being linked to lettuce, work continues to confirm this and identify the root cause of the outbreak with the growers, suppliers, and manufacturers so that actions can be taken to prevent a re-occurrence,” said Darren Whitby, head of incidents at the FSA.

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