The Belgian Salmonella surveillance programme 2005

Abstract

3 Federal Agency for the Safety of the Food Chain, DG Control Policy, Brussels, Belgium. Abstract The Belgian Salmonella Surveillance Programme on pig farms, organized by the Federal Agency for the Safety of the Food Chain, started in January 2005. The programme is built up in several stages. In the first stage the 10 % farms with the highest seropreva- lence (number of positive samples per farm) are identified. In the second stage, a follow- up programme is set up and implemented on these farms by the farm veterinarian and a specialist of the Animal Health Services. Blood samples taken as part of the national Aujeszky programme from fattening pigs with different weight categories and age are analysed for the detection of Salmonella. Serum samples from 50 randomly selected herds (N=50) were analysed for Salmonella-specific antibodies with an indirect ELISA (Idexx) and reported as s/p-ratio's. Results showed that 47, 39 and 28 herds were positive with a cut-off value of 0.25, 0.50 and 1.00 respectively. A herd was defined as positive when one animal tested positive. The first results will determine the cut-off value to be used in the Belgian Salmonella Surveillance Programme. Introduction Belgium is the third most important exporting country of pig meat in the world. With a production of 11 million fattening pigs a year, 50% accounts for domestic consumption and the remaining half is exported worldwide (FPS Economy - Statistics Division, 2004). In 2003 the National Reference Centre for Salmonella and Shigella (NRSS) received 12.894 human Salmonella isolates (Table 1) of which S. Enteritidis and S. Typhimurium are the most prevalent serotypes. Forty percent of all cases of human salmonellosis occurs in children younger than five years of age. During the summer (July until September) the NRSS counted more than 1.500 cases of human salmonellosis a month. From the end of the eighties until 1999 the number of cases of human salmonellosis in Belgium increased significantly and peaked in 1999 with a total number of 15.774 cases. This increase is mainly caused by the increase of Salmonella Enteritidis, mainly due to the consumption of fresh eggs. Nevertheless 20 % of all cases of human salmonellosis at this moment in Belgium are originating from pork (NRRS, 2003). Food safety has been a high political priority during the last decade in Belgium and the rest of the world. Other European countries such as Denmark, The Netherlands and Germany also have Salmonella control pro- grammes implemented. Since January 1st 2005, the Federal Agency for the Safety of the Food Chain has launched a Salmonella Surveillance Programme in pig herds based on serological screening on these herds. The pres- ent study describes the preliminary results of 50 randomly selected herds.