E.coli outbreak: 86 people taken to hospital
The total number of hospital patients linked to an E.coli outbreak now stands at 86, as more people are confirmed with the illness.
While cases have "slowed", the UK Health Security Agency (UKHSA) said there have been 45 further cases as of Tuesday, putting the total across the UK at 256 since the outbreak.
A number of food manufacturers have recalled sandwiches, wraps and salads sold in major supermarkets and retail chains over fears they are linked to the outbreak.
The Food Standards Agency (FSA) has said lettuce used in the products is thought to be the likely source.
All those who have been affected first developed symptoms before 31 May.
Read more:
Full list of products recalled by sandwich suppliers
"Although the rate of cases has now slowed, we expect the figure to rise as NHS laboratories refer specimens… for genomic sequencing which can link cases to this outbreak strain," the UKHSA said.
All the cases recorded involve Shiga toxin-producing E. coli O145 (Stec).
E. coli are a diverse group of bacteria, which are often found in the intestines of humans and animals and are normally harmless.
Some strains produce toxins that can make people very ill, such as Stec, which can cause diarrhoea - with about 50% of cases suffering from bloody diarrhoea.
Symptoms, which can also include stomach cramps and fever, can last up to two weeks in uncomplicated cases.
Read more:
What are the symptoms of E.coli?
Darren Whitby, head of incidents at the FSA, said it remains a "complex investigation" that has narrowed the cause down to a "small number of salad leaves".
"Although we are confident in the source of the outbreak being linked to a small number of salad leaves, which we identified early on through extensive food chain analysis, work continues to identify the root cause of the outbreak with the growers, suppliers and manufacturers so that actions can be taken to prevent a re-occurrence," he added.
Some patients, mainly children, may develop haemolytic uraemic syndrome, which is a serious life-threatening condition resulting in kidney failure.
A small proportion of adults may develop a similar condition called thrombotic thrombocytopenic purpura (TTP).
Short for Escherichia coli, E.coli is a bacteria that is commonly found in the lower intestine of warm-blooded organisms.
Most E.coli strains are harmless but some can cause serious food poisoning.
That is the case with Shiga toxin-producing E.coli (Stec), a bacterium that can cause severe foodborne disease.
All the cases recorded in this latest outbreak contain Stec.
Stec is often transmitted by eating contaminated food but can also be spread by close contact with an infected person.
It can also be caught through direct contact with an infected animal or where it lives.
The NHS advises people to call 111 or contact their GP if they are worried about their baby under 12 months or if a child stops breast or bottle feeding while ill.
Parents should also watch out for signs of dehydration, such as fewer wet nappies, and if older children remain dehydrated even after using oral rehydration sachets.