Denmark: Trends and sources in human salmonellosis

29.07.2013

The incidence of human salmonellosis in 2012 was 21.4 cases per 100,000, showing a slight increase from the 20.9 observed in 2011, but maintaining a lower incidence than observed during most of the last decade. Of these cases, 4.3/100,000 were caused by S. Enteritidis and 7.4/100,000 by S. Typhimurium (including 3.4/100,000 by the monophasic strains). Nearly half (45 percent) of all Salmonella infections were contracted while travelling abroad. It is particularly in connection with travels to Egypt, Thailand and Turkey that Danes become infected. Approximately half of the travel-related cases originated from these three countries. The most common type of Salmonella in Danes was Salmonella typhimurium which caused 415 cases in 2012. Salmonella enteritidis caused 242 cases, which was the lowest number since the action plans for combating Salmonella were introduced in the 1990s. Historically, this Salmonella type has been related to eggs, but today the majority of S. enteritidis cases, 77 percent, are contracted while travelling outside of Denmark.

No cases were attributed to Danish broiler meat in the Salmonella source account in 2012. This is only the second time in the 18 years the Danish Zoonosis Centre at the National Food Institute has prepared the Salmonella source account. The most likely reasons for the low incidence are that Danish law, since 2008, has required fresh broiler meat to be salmonella-free when put on the marked.
Denmark obtained special guarantees for Salmonella in table eggs July 1st 2012. By granting special guarantees to Denmark, the EU has acknowledged the effort made in Denmark for reducing the prevalence of Salmonella in table eggs. The special guarantees imply that eggs sold to Denmark should be followed by a specific certificate, and the flocks of origin must be tested negative for all Salmonella serotypes not only the serotypes covered by the EU legislation. Further, Danish eggs sold to other Nordic countries no longer need to be accompanied by specific certificates to facilitate trade.