In Reunion Island, Salmonella enterica subsp. enterica stands off a public health and is an economic problem particularly since inhabitant of Reunion island eat a lot of chicken and cook sausages 100% made of chicken (35 kg by people and by year).

This study aims (i) to define Salmonella prevalence all along the food chain production from broiler flocks before slaughtering to chicken meat, (ii) to identify risk factors of animal infection with Salmonella enterica in 60 chicken broiler flocks and (iii) to identify any cross contamination from farm to fork. To comply with these objectives, more than 1800 samples have been analyzed from the different steps of the chain: farm, transport, slaughterhouse involving vehicles and vectors (rodents, feral birds). We chose the technique of pulsed field gel electrophoresis (PFGE) and multiple loci VNTR analysis (MLVA) to explain genotypic relations among these serovars. Then association with antibioresistance patterns permitted to assess evolution of broiler chicken meat as a source of human infection.  More than 22 percent of chicken broiler flocks are infected by Salmonella enterica. The main serovars isolated from poultry at the end rearing period from faces and litters are:  Salmonella Virchow (38%), Salmonella Blockley (15 %), Salmonella Hadar (15%) and Salmonella Typhimurium (8%).

The genotypic relationships among these serovars have been investigated and the pulsotypes have been compared with the susceptibility to antimicrobials. This study showed a relative clonality among serovars including human strains but there is no relationship with the antimicrobial susceptibility profiles. It is the first time that a longitudinal epidemiological analysis of Salmonella present on Reunion Island is undertaken. It was very interesting to underline evolution of serovars which began few years ago on the island. These results show the importance of increasing the efforts to reduce Salmonella infection for broilers, reduce contamination for food industry and infection for humans.

[La communication intégrale]

Isabelle HENRY; Jef Reichardt; Sophie Granier; Gilles Salvat; Eric Cardinale, 2010. Epidemiological investigation of Salmonella enterica subsp. enterica all along the food chain poultry production in tropical area of the Reunion island. In: 13TH ASSOCIATION OF INSTITUTIONS FOR TROPICAL VETERINARY MEDICINE CONFERENCE 2010. Bangkok, August 2010.