Prevalence of Salmonella, Campylobacter, Listeria
monocytogenes and enterohemorrhagic E. coli O157
in animal foods in Belgium
Y. Ghafir1, B. China1, A. Chahed1, K. Dierick2, JM. Collard2, L. De Zutter3, D. Pierard4, and G. Daube1
1 Food Microbiology, Faculty of Veterinary Medicine, University of Liege, Belgium 2 Public Health Institute, Brussels, Belgium
3 Hygiene and Technology, Faculty of Veterinary Medicine, University of Ghent, Belgium 4 Department of Microbiology, Academische Ziekenhuis, Vrije Universiteit Brussel, Brussels, Belgium
Materials and Methods
Since 2000, the Belgian zoonosis surveillance program has assessed the contamination with Salmonella, Campylobacter, Listeria monocytogenes and enterohemorrhagic E. coli in cattle, pig, poultry and/or meat products. Between 100 and 300 samples were taken each year for each matrix.
The detection of Salmonella, Campylobacter and enterohemorrhagic E. coli O157 (EHEC) has been carried out with the official methods from the Ministry of Public Health (SP-VG M002 using Diasalm, SP-VG M003 using mCCDA and SP-VG M001 respectively). The detection of Listeria monocytogenes had been carried out with the AFNOR validated method Vidas Listeria monocytogenes 2 followed by an isolation on a chromogenic medium. Salmonella isolates were serotyped. For pork and beef carcasses, samples consisted on swabs.
Introduction
Salmonella and Campylobacter are the most important foodborne bacterial pathogen worldwide. Enterohemorrhagic Escherichia coli and Listeria monocytogenes constitute serious health problem in various countries for susceptible population. The assessment of their prevalence and level of contamination are essential for an efficient risk assessment program.
Results
Salmonella, Campylobacter, Listeria monocytogenes, EHEC and Yersinia enterocolitica in poultry, pork, salmon and beef are shown in Figures 1-3.
For Salmonella, a significant and constant decrease of pork meat samples is observed since 2000. Poultry contamination with Salmonella is stable since 2000. In chicken samples, the 3 main Salmonella serotypes were S. Enteritidis, S. Paratyphi B and S. Typhimurium. All the isolates were S. Enteritidis in layer. Close to the half the pork isolates were S. Typhimurium, followed by S. Derby and S. Ohio.
For Campylobacter, poultry is the main contaminated matrix. More than 70% of the Campylobacter species were coli in pork and jejuni in poultry.
According to the previous years, less than 1,5% of carcasses and cuts of beef contained EHEC.
For Listeria monocytogenes, the contamination of samples is close to the prevalence of the previous years, except for smoked salmon, where about 20% of samples were contaminated with Listeria monocytogenes in 2002 and 2003.
Discussion and conclusion
In comparison with pork, and beef, poultry is the most contaminated matrix by Salmonella and Campylobacter. This corresponds to the pattern of human isolates from foodborne infections in Belgium, where most of the Campylobacter species are jejuni and most of the Salmonella serotypes are Enteritidis, as in poultry
Acknowledgements
The Belgian Federal Agency for the Safety of the Food Chain (Ministry of Public Health) financially supported this study.
Fig. 1: Prevalence in poultry meat in 2004
30% 26% 3% 8% 24% 8% 21% 19%20% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Salmonella Campylobacter Listeria monocyt.
P re v al e n ce i n 2 0 0 4
chicken carcasses (SLM 1g-CAM 0,01g) chicken cuts (1g)
chicken preparation (SLM 1g-CAM&LMO 0,01g) layer carcasses (SLM 0,1g-CAM 0,01g)
Fig. 3: Prevalence in beef meat in 2004
1% 1% 0% 16% 3% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Salmonella EHEC Listeria monocyt.
P re v al e n ce i n 2 0 0 4 carcasses (1600cm2) cuts (25g)
minced meat (SLM 25g - LMO 1g)
Fig. 2: Prevalence in pork meat, meat products and salmon in 2004
5%3% 21% 0% 8% 12% 10% 9% 4% 1% 8% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Salmonella Campylobacter Listeria monocyt. Yersinia
P re v al e n ce i n 2 0 0 4 pork carcasses (600cm2) pork (cuts 25g)
pork minced meat (25g SLM-1g LMO) cooked ham 25g
pate (25g) salami (1g) cooked salmon (25g)
