F. Humbert et G. Salvat, DETECTING AND PREVENTING RISKS OF TRANSMITTING SALMONELLAS AMONG POULTRY FARMS IN EUROPE, Revue scientifique et technique - Office international des epizooties, 16(1), 1997, pp. 83-90
While salmonellas can cause disease problems among poultry, they remai
n essentially a concern for public health, as a cause of outbreaks of
food poisoning. The principal site of multiplication of these bacteria
is the digestive tract, particularly the caecum, which may result in
widespread contamination of the environment. The pathogenicity of salm
onellas depends on the invasive properties and the ability of the bact
eria to survive and multiply within cells, particularly macrophages. T
hese properties are the source of vertical transmission which, in the
case of survival of the embryo, can result in contamination of a flock
or, in the case of embryonic mortality, can result in an explosion of
contaminated eggs. Salmonella infection can be diagnosed by isolating
the bacteria and/or serological testing of the flock. European Union
Directive 92/117/EC, modified by Directive 97/22/EC, stipulates either
the destruction of infected flocks of breeding birds, or decontaminat
ion of the flock in an effective way, before normal trade in products
can be resumed. Noteworthy examples of effective measures suitable for
prophylaxis of Salmonella infection in poultry flocks include the sla
ughter of infected breeding stock, the creation of sanitary barriers a
t building entrances, heat treatment of feed, the use of competitive e
xclusion, selection of breeds genetically resistant to Salmonella, and
occasional vaccination and antibiotic treatment. However, the most ef
fective means of reducing food poisoning remains adequate cooking of f
ood and maintenance of the cold chain.