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From January 2001 to May 2002, 300 chicken carcasses from retail shops in Dakar were examined for prevalence of Salmonella and Campylobacter. Of these, 146 were fresh products, 58 were refrigerated and 96 were frozen. Salmonella was isolated from 96 (32%) of the carcasses analyzed. The most prominent Salmonella serovars were Salmonella Hadar (41.6%) and Salmonella Brancaster (20.8%). Campylobacter spp. was isolated from 168 (56%) of the samples. C. jejuni was more frequently isolated (59%) than C. coli (27%). The contamination rates for Campylobacter were significantly different in relation to the type of carcass: 76% for fresh, 53% for chilled and 28% for frozen.

Campylobacter resistance to antimicrobial agents appears as an emerging public health problem in industrialized countries, but, on the other hand, only few data on the subject are available in developing countries. To assess antibiotic susceptibility of Campylobacter strains in Senegal, skin samples were collected from 250 chicken carcasses from January 2001 to October 2002. Among 204 Campylobacter strains isolated, two species were identified: C. jejuni (59%) and C. coli (41%). In vitro susceptibility to five antimicrobial drugs (amoxicillin, amoxicillin-clavulanic acid, erythromycin, nalidixic acid and ciprofloxacin) was determined by the E-test method. Minimum inhibitory concentrations (MICs) showed 34% of Campylobacter isolates were ciprofloxacin resistant with a high level of resistance (MIC ≥ 32 mg/l) in 25% of both species. Cross-resistance between nalidixic acid and ciprofloxacin was found in 96% of quinolone-resistant strains. The level of amoxicillin resistance was statistically higher for C. coli than for C. jejuni (20.2 versus 10.8%), but all the strains were susceptible to amoxicillin combined with clavulanic acid. Both species showed low resistance to erythromycin. Multiresistant phenotype to three of the drugs tested was found in 9.8% of the strains: 15.5% of C. coli strains and 5.8% of C. jejuni strains. No strain was resistant to four or more of the drugs studied. Further studies appear necessary to evaluate antibiotic resistance of Campylobacter isolated in human and animal samples in order to control the emergence of new multidrug-resistant strains in Senegal.

Microbiological analysis of a broiler chicken carcass revealed the presence of a new Salmonella serotype. It is characterized by two genes that express resistance to antibiotics, except to the very last quinolones. This serotype poses a threat as it has been found in human samples in association with high temperature and diarrhea. The onset of this Salmonella may result from the anarchic use of antibiotics in poultry production.