The number of E. coli cases in Scotland has risen amid a huge product recall.

New data from the UK Health Security Agency shows there have been 45 further cases of the infection as of Tuesday, taking the total number of confirmed cases across the UK since the outbreak began to 256.

All those who have been affected first developed symptoms before May 31.

The UKHSA said: “Although the rate of cases has now slowed, we expect the figure to rise as NHS laboratories refer specimens to UKHSA for genomic sequencing which can link cases to this outbreak strain.”

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In Scotland, there have been 56 confirmed cases of E. Coli as of June 18.

Previously, on June 14, only 35 cases of the infection were recorded in the country.

Meanwhile, there have been 168 in England, 29 in Wales, and three in Northern Ireland.

Several 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 has said lettuce used in the products is thought to be the likely source of the outbreak.

All the cases recorded involve Shiga toxin-producing E. coli O145 (Stec).

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Darren Whitby, head of incidents at the Food Standards Agency said: “Several sandwich manufacturers have now taken precautionary action to withdraw and recall various sandwiches, wraps, subs and rolls, as food chain and epidemiological links have enabled us to narrow down a wide range of foods consumed to a small number of salad leaves that have been used in these products.

“This remains a complex investigation and we continue to work at pace with the relevant businesses and local authorities to ensure necessary steps are being taken to protect consumers.

“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.

“We will remain vigilant until the root cause of the outbreak is confirmed and we are keeping an open mind about possible causes of the outbreak.”

E. coli are a diverse group of bacteria that are normally harmless and live in the intestines of humans and animals.

However, some strains produce toxins that can make people very ill, such as Stec.

People infected with Stec can suffer diarrhoea, and about 50% of cases have bloody diarrhoea.

Other symptoms include stomach cramps and fever.

Symptoms can last up to two weeks in uncomplicated cases.

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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).

Stec is often transmitted by eating contaminated food but can also be spread by close contact with an infected person, as well as direct contact with an infected animal or where it lives.