A multi-agency investigation is being carried out into cases of listeria infection in nine seriously ill hospital patients in England, five of whom have sadly died.  No infections have been found in Wales, Scotland or Northern Ireland.

On 14 June, Public Health England (PHE) announced the number of deaths related to pre-packed sandwiches and salads at hospitals had risen from three to five. It also announced the number of confirmed cases had risen from six to nine.

The additional cases were identified after PHE analysed previously known cases of listeria from the past two months to see if they were linked to this outbreak using Whole Genome Sequencing analysis.

PHE had initially announced on 7 June, six confirmed cases of listeria which two patients from Manchester Royal Infirmary and one at Aintree Hospital had died.

Evidence suggests that all individuals ate the affected products before the withdrawal took place in hospitals on the 25 May 2019.

The source of the outbreak has been linked to Staffordshire sandwich producer The Good Food Chain which has now voluntarily ceased production while investigations continue. 

Affected sandwiches and salads were also withdrawn from hospitals when the link to listeria infections were first identified.

The Good Food Chain was supplied with meat from North Country Cooked Meats, which subsequently produced a positive test result for the outbreak strain of listeria has also voluntarily ceased production.  Their distributor North Country Quality Foods have also voluntarily ceased production.

Dr Nick Phin, Public Health England, said:

“To date, there have been no patients linked to this incident outside healthcare organisations, but we continue to investigate. Swift action was taken to protect patients and any risk to the public is low. PHE is continuing to analyse all recent and ongoing samples of listeria from hospital patients to understand whether their illness is linked to this outbreak.”

Listeria has such a long incubation period and can withstand cold temperatures such as refrigeration and even freezing.

Public Health England, The Food Standards Agency, Public Health Wales, Food Standards Scotland, Health Protection Scotland and a number of local authorities are investigating the outbreak.