Antimicrobial resistance in salmonellae from humans, food and animals in Spain in 1998.
We studied 1710 Salmonella: spp. isolates from human (1051), food (421) and animal (238) sources. They were tested by the disc diffusion method for susceptibility to 12 different antimicrobial agents. The incidence of resistance and multiple resistance (MR) among the salmonella strains of different origins, the relationship between their most frequent serotypes and phage types (PTs) and their antimicrobial resistance patterns were determined. In general, the incidence of resistance and MR was significantly higher in animal isolates than in human and food isolates (P < 0.05). Resistance to each individual drug among the human isolates and food isolates was very similar, with resistance to ampicillin, tetracycline, streptomycin and sulphonamides most frequently observed. MR has remained uncommon in Salmonella enteritidis. Nevertheless, 90% of PT6A of the human isolates and 100% of the food isolates were ampicillin resistant and 80 and 60%, respectively, of the PT1 isolates were nalidixic acid resistant. Salmonella typhimurium was the most multiresistant serotype in the three sample populations and ten different patterns of MR were seen. Almost 100% of the Salmonella hadar isolates, from human and food sources, were resistant. We recommend restriction of the use of antibiotics in veterinary medicine in order to reduce the selection and spread of multiresistant strains.
Laboratorio Nacional de Referencia de Salmonella y Shigella, Centro Nacional de Microbiología, Virología e Inmunología Sanitarias, Instituto de Salud Carlos III, Carretera de Majadahonda a Pozuelo, s/n, 28220 Majadahonda, Madrid, Spain.
S
S
Cruchaga
A
A
Echeita
A
A
Aladueña
J
J
García-Peña
N
N
Frias
M A
MA
Usera
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002417:Cattle; D002645:Chickens; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D005516:Food Microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D012475:Salmonella / Q000187:drug effects* / Q000254:growth & development; D012477:Salmonella enteritidis / Q000187:drug effects / Q000254:growth & development; D012486:Salmonella typhimurium / Q000187:drug effects / Q000254:growth & development; D012756:Sheep; D013030:Spain
D000900:Anti-Bacterial Agents