The Swedish Food Administration has recommended new routines for the slaughter of pigs, while health experts are advising Swedes to wash knives and chopping boards that have been used for pork as carefully as if they had been used for chicken.
The bacteria, yersinia, produces the same symptoms as salmonella and is closely related to the bacteria behind the Black Death.
Among children the bacteria can lead to fever, bloody diarrhoea and vomiting, while in adults the effect is usually abdominal pains. Quarter of those affected are under the age of four, and half are under 15.
There were 804 cases of the illness in 2004, an increase of 45% since 2001. Sweden is the third worst-affected country in the EU.
“The bacteria can be found in glands in the neck of the pig and it also appears in the intestine,” said Sven Lindgren, professor in microbiology at the Swedish Food Administration, to TT.
According to Lindgren it is important to tighten the quality of hygiene in slaughterhouses.
“Then the number of cases of the disease will fall,” he said.
The Swedish Food Administration described the rise in cases as “undesirable”, but said that it was not “alarming”.
Since the increase was identified in 2004 no direct measures have been taken by Sweden’s slaughter firms.
“No, routines have not generally been changed,” said Åke Rutegård, managing director of the Swedish Meat Industry Association.
“But on the other hand this is well known among the slaughter companies and the risk is handled with existing routines and individual controls.”
Nevertheless, Rutegård confirmed that the prevalence of the yersinia bacteria was on the agenda at an industry organisation meeting next week.
“We are prepared and can quickly introduce new routines if they are needed,” he said.
Consumers are advised to cook pork thoroughly and carefully.
“But even then the bacteria can be spread if you use the same knife and chopping board for pork and then for other food,” said Yvonne Andersson, head of epidemiology at the Institute for Infectious Diseases, to Svenska Dagbladet.
The hygiene process for pork should be as careful as that for chicken, said experts, including washing hands after preparation.