The survey of 28,518 retail-sold eggs found that just one in every 290 boxes of six eggs on sale has any salmonella contamination, compared with 1 in 100 in a 1995/96 survey. It found no difference in levels between free range and other eggs.
"This is very reassuring and good news for the consumer. If you're buying UK-produced eggs from shops and markets, the possibility of any salmonella contamination is very low indeed and significantly lower today than in the mid-1990s," said Dr Judith Hilton, head of Microbiological Safety at the Food Standards Agency (FSA), the food safety body that carried out the research.
Some foodborne diseases are well recognised, but are considered emerging because they have recently become more common. Outbreaks of salmonellosis have been reported for decades, but within the past 25 years the disease has increased in incidence on many continents. In the Western hemisphere and in Europe, Salmonella serotype Enteritidis (SE) has become the predominant strain. Investigations of SE outbreaks indicate that its emergence is largely related to consumption of poultry or eggs.
Groups in society vulnerable to this foodborne pathogen include the elderly, babies and toddlers, pregnant women, and people who are already unwell and more vulnerable to infection.
The results are particularly welcome in light of new European legislation in place by mid-summer this year that requires all eggs from member states to be stamped with a code indicating their country of origin. UK eggs will have the letters 'UK' stamped on them.
As the survey shows, although the chances of eggs being contaminated are now very low, eggs cannot be guaranteed to be salmonella-free, whatever the source or type.
All types of retail eggs were included in the survey, with eggs from caged production accounting for 50 per cent of total eggs sampled, free-range eggs 16.9 per cent, barn eggs 16.5 per cent and organic eggs 16.6 per cent.
Back in 1998 a programme was set up to vaccinate UK laying hens against a common type of salmonella (Salmonella Enteritidis), leading to a steady decrease in the number of cases of human illness from this type of salmonella. The number of reported Salmonella Enteritidis cases is now at its lowest level since the late 1980s.
But, says the FSA, there was a statistically significant higher prevalence of salmonella contamination of eggs from medium sized retailers - independent and local shops, than large retail outlets.
Of the nine isolates from salmonella-positive samples, seven (78 per cent) were S. Enteritidis and of these, three were S. EnteritidisM phage type 4 (PT4).
There were also single isolates of S. Infantis and S. Livingstone. All of the salmonella isolates were fully sensitive to ten antimicrobial agents and none of the three S. Enteritidis PT4 isolates corresponded to known vaccine strains.
Salmonella Infantis, S. Livingstone and S. Enteritidis PTs 4, 6 and 12 were found in previous egg surveys. In addition to the nine salmonella positive samples there were a further 5 egg samples which were reported as positive for S. Dublin.
"The small number of positive samples points towards random contamination from the production environment rather than any systemic contamination from infected flocks," concluded the FSA.
Salmonella alone costs the EU an estimated €2.8bn.