As of September 8, there are 40 confirmed cases.
Initial investigations have indicated that pre-packed salad is the most likely cause of the outbreak. Dr Anjila Shah from PHE’s North West’s Cheshire and Merseyside Health Protection team said: “We have been working with colleagues nationally and with the Food Standards Agency to investigate the cause of this outbreak.
“To date seven cases have been confirmed across the Cheshire and Merseyside area and public health measures have been put in place to prevent further infection.
“Investigations into these cases is on-going so it is not possible to speculate further as to the cause and source of the infection.”
Paul Cleary, consultant epidemiologist for Public Health England said: “The public can protect themselves from getting, and spreading E. coli through good hygiene practices.
“This is particularly important when handling or preparing food, as consuming contaminated food or water are common sources of infection.
“Foods that require cooking should be cooked thoroughly and all fruits and vegetables eaten raw should be washed to help remove bacteria from the outside.
“Ready-to-eat pre-packed salads do not generally need to be re-washed unless it states otherwise on the packet.”