One dead and dozens ‘severely ill’ in UK-wide E. coli outbreak linked to minced beef

A MYSTERIOUS E. coli outbreak that swept across the UK last year left one dead and dozens ‘severely ill’, as officials raced to find the source of the outbreak.

Now, investigations have confirmed minced beef as the probable cause.

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The spate of severe gastrointestinal illnesses was first detected by the UK Health Security Agency (UKHSA) surveillance systems in June 2023.

Health officials were were able to determine that the outbreak was being cause by Shiga toxin-producing Escherichia coli (STEC) O183:H18, a rare strain of E. coli that leaves sufferers with bloody diarrhoea, as well as tummy pain, fever and vomiting.

But how Brits were being contaminated with the bacteria in the first place has remained a mystery.

At the time, officials suggested hard cheese, strawberries cucumbers, peppers and watermelon could be the source.

As the STEC strain causing the illnesses is rarely seen in the UK and patients seemed to be experiencing severeoutcomes, and an incident management team meeting was convened.

A report published in the journal Microbial Genomics confirmed that sufferers likely picked the illness up from eating beef burgers or minced beef.

A PROCESS OF ELIMINATION

Between May and July 2023, there were 27 confirmed cases linked to the STEC outbreak and one probable one.

One person developed hemolytic uremic syndrome (HUS) after their bout of E. coli – this is a rare kidney condition can cause damage to red blood cells and blood vessels and result in kidney failure.

Another person passed away in connection to the outbreak, though their death certificate doesn’t state whether STEC caused or contributed to their death.

Sufferers were aged between six months and 74 years – though almost half (42  per cent) of the cases occurred in children aged nine and under.

Cases were distributed across the UK, with 21 (81 per cent) reported in England, three in Northern Ireland, two in Scotland and two in Wales.

Patients infected with STEC can be struck by a wide array of symptoms, ranging from mild diarrhoea to severe, blood-stained diarrhoea, abdominal pain, fever and vomiting.

Of the 24 patients study authors were able to gather information on, 17 said they’d been struck with bloody diarrhoea and eight of them went to hospital.

Researchers also gathered data on what half the patients ate in the lead-up to their illness, with 68 per cent saying they’d consumed cooked chicken.

Meanwhile, 55 per cent said they’d eaten cooked beef, 68 per cent said pasteurised milk and 77 per cent said they’d eaten hard cheeses.

Ten of the patients later completed questionnaires to collect a detailed food history two weeks before the onset of symptoms.

Commonly reported food items were strawberries (70  per cent), pasteurised milk (80 per cent), hard cheeses (100  per cent), chicken (100 per cent), and beef (100  per cent).

All the commonly reported foods were investigated, but it was deemed unlikely that chicken and pasteurised dairy products could have transmitted STEC infections, as no previous STEC outbreaks linked to these food items had been previously recorded in the UK.

“In contrast, cattle are well established as an animal reservoir for STEC, and undercooked beef meat products, particularly beef burgers and beef mince, are often implicated in food-borne outbreaks of STEC,” researchers wrote.

“All ten cases that completed a questionnaire reported consumption of either beef burgers, beef mince cooked at home or other beef mince products,” they added.

Recent outbreaks of STEC in the UK have been linked to person-to-person transmission in nursery schools, contact with animals at petting farms, while food-borne outbreaks have been linked to unpasteurised dairy products and fresh produce, study authors noted.

OUTBREAK ‘LIKELY MORE WIDESPREAD’

The Food Standards Agency (FSA) launched a food chain investigation examining common beef suppliers and processors, in order to identify where the contaminated beef had come from.

“However, the complexity of the beef industry supply lines hampered progress,” researchers said.

“Food chain investigations were de-escalated once the outbreak was over, and the source of the contaminated food was never confirmed.”

They warned that “the outbreak is likely to be more widespread than described here” as many laboratories in England don’t perform the required tests to identify the rare E. Coli strain and so wouldn’t have been able to diagnose it.

E. coli O183 is an extremely rare serotype, with only 15 cases in the UK since 2016.

Researchers suggested that this STEC serotype could have been imported into the UK or it might be a domestic strain of E. coli that has recently acquired elements from an external source.

“Whether or not STEC O183:H18 will emerge as an on-going threat to public health remains to be seen,” they added.