An investigation has been launched into a major outbreak of food poisoning linked to cooked ham which has struck in Leeds.
Experts say 51 people across England and Wales have been infected by the salmonella bug, with clusters in Leeds, Stafford, Cumbria and the Thames Valley since the outbreak was first detected in Wales.
At least nine people aged 22 to 77 in Yorkshire have been hit, forcing the hospitalisation of two aged 25 and 68.
Public Health England (PHE) said the cases were being linked to cooked ham bought from small independent butchers.
Tests had not shown salmonella but did reveal other hygiene issues, leading to the withdrawal of some batches of ham by one supplier.
Nationally, people aged between seven months and 87 have been affected, with nine requiring hospital treatment. Other cases are being investigated.
Bob Adak, head of the gastrointestinal diseases department at PHE, said all possible leads were being followed.
“Although the source of the outbreak has not been confirmed some of the cases have been linked to the consumption of cooked ham sold by a small number of independent butchers,” he said.
“Investigating outbreaks of foodborne illness is a complex process as people have to try and remember what they ate some weeks prior to becoming unwell. In this instance many reported eating cooked meats.
“The Food Standards Agency is following all possible leads along with Environmental Health to try and establish the source of the outbreak. This process is ongoing.”
Salmonella food poisoning is usually caused by eating contaminated raw or undercooked food such as meat, eggs, and dairy products. Symptoms can include diarrhoea, stomach cramps, vomiting and fever.