More than 200 Britons have now been affected by a rare strain of E. coli linked to contaminated lettuce leaves.
Food safety chiefs said they were “certain” a type of lettuce, named Apollo, was behind the diarrhea bug outbreak.
However, how exactly they were contaminated has not yet been determined.
Currently more than 60 sandwiches, wraps and salads are sold in 11 large stores with a “do not eat” warning. due to concerns that they could contain Shiga toxin producing E.coli (STEC).
However, this is not the first time lettuce has been blamed for a mistake.
Studies suggest that leafy greens are responsible for half of all E. Coli outbreaks.
Food safety chiefs have said they are “certain” Apollo salad caused the diarrhea bug outbreak. However, efforts to confirm the root cause are ongoing
She saw more than 60 sandwiches, wraps and salads sold in 11 big box stores with “do not eat” warnings over concerns they could contain Shiga toxin-producing E.coli (STEC).
In December, a 17-year-old girl from Buckinghamshire was fighting for her life after contracting a deadly strain of E. Coli. Antonia Hay is believed to have caught STEC-HUS, caused by E. coli O157, from food at a Christmas market in Great Missenden
Experts believe that the texture of lettuce may make it more susceptible to bacteria, and the fact that it is not cooked, which would normally kill insects, increases the risk.
Professor Paul Hunter, a renowned infectious disease expert at the University of East Anglia, told MailOnline: ‘During watering during growth, potentially contaminated water can sit on lettuce leaves.
“The rough and waxy surface of the leaf also makes it difficult to wash off E. coli.
“As for whether E. coli can penetrate lettuce tissue, it probably can, although the evidence is somewhat conflicting.
“The main risk comes from bacteria attached to the surface of the leaves. Most other vegetables are either peeled or boiled before consumption.
“Things like cucumbers, tomatoes, and peppers may not be cooked, but they grow a little above ground, so they’re less likely to be contaminated.”
A 2019 research review co-authored by Professor Hunter also analyzed 35 STEC outbreaks linked to lettuce between 1995 and 2018.
Eight were found to have “poor practices” where vegetable processing “may have contributed to the outbreak”, such as insufficient disinfection.
Another six were linked to animal feces near grower fields.
“Where the type of lettuce was listed, it was usually Cos lettuce, although iceberg lettuce and Mesclun lettuce were lumped into one,” Professor Hunter told MailOnline.
“We also found that ready-to-use bagged lettuce is a common factor.”
Experts say that all lettuce should be thoroughly washed by immersing it in cold water.
Storing vegetables is also key: if the salad bags are in the fridge and the temperature is below four degrees, the bacteria does not multiply as quickly.
Experts also say the recent wet and warm weather may create an “ideal” breeding ground for E. coli to spread.
Professor Eileen Wall, head of research at Scotland’s Rural College (SRUC), an agricultural and life sciences research institution, said: “Rain can cause contaminated water to splash onto lettuce leaves, while heat provides a favorable temperature for the bacteria. proliferation.’
The aspiring actress spent nearly two weeks in intensive care, returning home only temporarily on Christmas Day. She had several surgeries – including one to remove part of her intestines – and a blood transfusion as her kidneys failed, forcing her to undergo dialysis.
Antonia’s father posted on Facebook asking if people had also experienced similar symptoms
The bacteria could spread to lettuce through irrigation water — especially if the water is contaminated with feces, she added.
Meanwhile, Nicola Holden, professor of food safety at SRUC, warned that wet weather could also have played a role.
She said: “Rainy weather means that field-grown crops will have higher leaf crown moisture.
“We know that STEC prefers high humidity conditions.”
The UK Health Safety Agency (UKHSA) typically sees around 1,500 confirmed STEC infections per year.
Studies have even shown that leafy greens are responsible for up to 58 percent of E. Coli outbreaks. Experts believe the texture of lettuce can make it more susceptible to bacteria, even getting stuck inside the vegetable
But officials raised the alarm after 211 Britons were struck in just two weeks – from May 25 to June 11.
Of these, 147 were in England, 27 in Wales and 35 in Scotland.
Only two cases have been recorded in Northern Ireland, although officials say the individual likely caught the bug in England.
At least 67 people were also admitted to hospital.
Victims include children as young as two, although the majority are young adults.
The UKHSA said it expected the number of people falling ill to rise further as it carried out further research using genome sequencing to verify which E. coli cases were linked.
While no bacteria was found directly in supermarket produce, more than 60 sandwiches, wraps and salads were recalled as a “precautionary measure”.
STEC is considered extremely infectious and can cause hemolytic uremic syndrome (HUS), a life-threatening condition that can lead to kidney failure, in up to 15 percent of cases.
Children under the age of five are at the highest risk of HUS.
A small proportion of adults may develop a similar condition called thrombotic thrombocytopenic purpura (TTP).
In December, a 17-year-old girl from Buckinghamshire was fighting for her life after contracting a deadly strain of E. Coli.
Antonia Hay is believed to have caught STEC-HUS, caused by E. coli O157, from food at a Christmas market in Great Missenden.
The aspiring actress spent nearly two weeks in intensive care, returning home only temporarily on Christmas Day.
She had several surgeries – including one where part of her intestine was removed – and a blood transfusion as her kidneys failed, forcing her to undergo dialysis.
However, it is not known what type of food caused Antonia to become ill.
Her older sister Jemima Hay said she was “lucky to be alive” and described the situation as “an absolute nightmare which has torn our family apart”.
On the GoFundMe page, she wrote: ‘[Antonia] throughout this time he continued to show amazing determination and strength, despite tremendous stress, pain and trauma – all combined with an extreme phobia of injections.
“He is the youngest person ever admitted to the ICU where he is currently.”
She added: ‘She feels like her dreams have been ripped away from her as her studies on her performing arts course will be severely affected.’
People have been advised to contact NHS 111 or their GP if they or their children show any symptoms of an E.coli infection.
In children under five, this may include a lack of interest in breastfeeding or bottle feeding and signs of dehydration such as fewer wet nappies.
Adults and children are advised to call NHS 111 or their GP if they have been vomiting for two days or have had diarrhea for a week.
Anyone with bloody diarrhea or bleeding from the gout should call NHS 111 or their GP straight away.