[Antibiotic of resistence profile of Salmonella spp. serotypes isolated from retail beef in Mexico City].

Objective: To determine the serotype and antibiotic resistance profile of Salmonella spp. isolated from retail ground beef in Mexico City.

Materials And Methods: A total of 100 samples of ground beef were analyzed. The pathogen was isolated by conventional methods and confirmed by PCR (invA gene, 284 bp).The antibiotic resistance profile was determined by the Kirby-Bauer method while serotyping was performed according to the Kauffman-White scheme.

Results: We isolated a total of 19 strains of Lomita (6), Derby (4), Senftenberg (2), Javiana and Cannsttat (1) and undetermined (5) serotypes. The strains showed a high resistance rate to ampicillin (18/19), carbenicillin (16/19), tetracyclin (13/19), and trimethoprim-sulfamethoxazole (13/19). Multidrug resistance was observed in 14 isolates.

Conclusions: Several Salmonella spp. serotypes of public health significance are circulating in ground beef sold in the major Mexican city. Some of these strains are multi-drug resistance.