Health Protection Scotland (HPS) and a number of local authorities are now investigating the source of listeria infections linked to pre-packed sandwiches.
Officials say the infections affected six seriously-ill hospital patients, three of whom have died. It can kill in severe cases.
Sandwiches and salads affected are not being produced while investigations continue and products were withdrawn from hospitals when the link to the Listeria infections was identified.
The Good Food Chain company, based in Staffordshire, central England, has voluntarily ceased production while an investigation takes place, PHE said.
Nick Phin, an infection specialist at PHE, said that in this outbreak, the risk of further cases was relatively low, as was the risk to the general public.More news: Joe Jonas releases song he wrote for wife Sophie Turner
Three Britons have died of food poisoning after eating pre-packaged sandwiches, United Kingdom health authorities said Friday, stressing that the risk to the wider public remained "low".
'We, alongside with the FSA, colleagues in local authorities and the NHS bear worked mercurial to search out out the seemingly explanation for this outbreak and brought motion to decrease the possibility to the public's properly being.
However it can have more serious consequences among those with pre-existing medical conditions, pregnant women and those with a weak immune system.
This industry and North Country Quality Meals, which they distribute by, bear additionally voluntarily ceased production.
Dr Colin Sullivan, chief operating officer at the FSA, said: "Our sympathies are with the families of those patients who have tragically passed away".More news: Nicole Curran Photos, News and Videos
The Good Food Chain had been supplied with meat produced by North Country Cooked Meats which tested positive for the outbreak strain of listeria.
"The best way to prevent listeriosis is to practice good food hygiene".
The time between publicity to the organism and the advance of the illness will even be as a lot as 70 days. We advise that chilled food should be put in a fridge or other suitable equipment as soon as it is delivered. "Food products are permitted to be out of temperature control for limited periods, providing there is no risk to food safety, to accommodate the practicalities of transport and storage", Public Health England stated.
All six cases have been in England, with no cases identified in Scotland, Wales or Northern Ireland. Both companies have ceased production of food products. "However, due to a relatively long incubation period it's possible that there could potentially be some more cases".More news: Regulator proposes radical overhaul of "dysfunctional" bank overdraft charges