One in five slaughter pigs destined for human consumption in the UK could be infected with salmonella, a new report from the European Food Safety Authority has warned.

The survey sampled more than 19,000 slaughter pigs across 25 member states between October 2006 and September 2007. It found a 21.2% salmonella prevalence in the UK slaughter pigs tested, compared with an EU average of just 10.3%.

EFSA stressed that as it tested for the presence of salmonella in the animal's lymph nodes, which are usually removed from the carcase upon slaughter, it did not necessarily mean edible meat from the carcase would contain the same levels of the virus as those found in the nodes. However, infection in the lymph node could be associated with infection elsewhere in the carcase or gut, it warned, adding that poor slaughterhouse hygiene could be the cause of contamination.

BPEX sought to play down the report's findings. "The results do show the UK is towards the bottom of the league table, but the industry has already taken major steps to remedy the situation", said a spokesman for BPEX. "It is important to reassure consumers salmonella is heat-sensitive and cooking pork to 70C or more for two minutes destroys it", he added.

The report came as the FSA launched a new GermWatch campaign to target the 120,000 cases of salmonella and campylobacter poisoning expected to occur in England and Wales this summer. The FSA claimed the incidence of food-borne disease, which costs the economy £1.5bn a year in England and Wales, increased 1.7% between 2005 and 2006, the first rise since 2000.

To front the campaign, the FSA has introduced a character called Grubeye, which will be used in schools and by local authorities to get the message across. "With enough cases of salmonella and campylobacter to fill Wembley Stadium in three months, this summer might be unpleasant for some people," said FSA chief scientist Andrew Wadge.