Phage typing and Multidrug resistance profile in S. Typhimurium isolated from different sources in Brazil from 1999 to 2004

Salmonella Typhimurium has become a widespread cause of salmonellosis among humans and animals worldwide. In Brazil, Salmonella Typhimurium (STM) is one of the most prevalent serovars isolated from food for human consumption. The uncontrolled sale and use of antimicrobials in agriculture and for treating human patients contributes to increase multidrug resistance of this serovar. In the present study, a total of 278 STM isolates from different sources and regions of Brazil over the period 1999 to 2004 were phage typed and analyzed for their antimicrobial resistance profile at Laboratory of Enterobacteria, Oswaldo Cruz Institute, FIOCRUZ. The main STM phage types isolated were DT 193 (64.3%), DT 19 (17.4%) and DT 18 (4%). Others phage types as DT 10 (2%), DT 27 (3.24%), DT 13 (0.36%), DT 22 (0.36%), DT 28 (0.36%), DT 29 (0.36%) and DT 149 (0.36%) were obtained in low percentages. A total of 54% STM strains were resistant to three or more antimicrobial classes, while no resistance to third generation cephalosporin or ciprofloxacin was identified in these strains. Those results show the STM phage types circulating among animals, food for human consumption and humans in Brazil as well as the increasing of multidrug resistance. The surveillance of STM strains based on phage typing and antimicrobial resistance profile are useful for detecting outbreaks, identifying sources of infection and implementing prevention and control measures. Salmonella Typhimurium é considerada uma das principais bactérias causadoras de salmonelose nos animais e no homem em todo o mundo. No Brasil, Salmonella Typhimurium é um dos mais prevalentes sorovares isolados de alimentos para consumo humano. O uso indiscriminado de antibióticos em produtos agrícolas e no tratamento de pacientes humanos tem contribuído para aumentar a multirresistência desse sorovar a diversos antimicrobianos. No presente estudo, 278 cepas de STM foram selecionadas de diferentes fontes e regiões do Brasil, no período de 1999 a 2004 e realizadas a fagotipagem e análise do perfil de resistência antimicrobiana no Laboratório de Enterobactérias, Instituto Oswaldo Cruz, FIOCRUZ. Os principais fagotipos isolados foram DT 193 (64,3%), DT 19 (17,4%) e DT 18 (4%). Os fagotipos DT 10 (2%), DT 27 (3,24%), DT 13 (0,36%), DT 22 (0,36%), DT 28 (0,36%), DT 29 (0,36%) e DT 149 (0,36%) foram isolados em menores percentuais. Um total de 54% das cepas de STM foi resistente a três ou mais classes de antimicrobianos e não foi observa