Epidemiology of resistance to quinolones in Salmonella

Abstract

-Fluoroquinolones account for about 11% of antimicrobial prescriptions in human medicine worldwide and represent the drug of choice for the treatment of a wide range of human infectious diseases. They were introduced into veterinary medicine in Europe in the late 1980s and early 1990s and in the USA in 1995. Following their introduction, resistant strains of bacteria, including Salmonella, started to emerge. Resistance to quinolones depends on chromosomal mutations and the subsequent spread of resistant clones. While the selective pressure caused by the use of quinolones facilitates their epidemic transmission, the resistant mutants may spread independently of quinolone use. In view of the key role of this group of antimicrobials in human medicine and the position of Salmonella as the leading cause of food-borne infections in many countries, the public health hazard posed by quinoloneresistant zoonotic Salmonella serovars has been a subject of concern. The fluoroquinolones are on the WHO list of drugs that should be reserved for human use. Considering the mounting evidence that quinolone-resistant zoonotic Salmonella are the cause of severe, sometimes fatal, infections in humans, the use of fluoroquinolones in food animals should be discontinued or severely restricted. Such an intervention should be accompanied by prudent use measures involving all other groups of antimicrobials to reduce the need for fluoroquinolones in veterinary medicine. quinolone resistance / epidemiologyRésumé -Épidémiologie de la résistance aux quinolones chez Salmonella. Les fluoroquinolones représentent environ 11 % de la totalité des prescriptions d'antibiotiques en médecine humaine et sont les antibiotiques de choix pour le traitement d'une grande variété de maladies infectieuses humaines. En médecine vétérinaire, ils ont été introduits en Europe à la fin des années 80-début des années 90, et aux USA en 1995. Après leur introduction, des souches de bactéries résistantes, dont des Salmonella, ont commencé à émerger. La résistance aux quinolones est due à des mutations chromosomiques et à la propagation ultérieure de clones résistants. Alors que la pression de sélection par utilisation de quinolones facilite leur transmission épidémique, les mutants résistants peuvent se propager indé-pendamment de l'utilisation de quinolones. Étant donné le rôle-clé de ce groupe d'antibiotiques en médecine humaine, et le fait que Salmonella soit la cause principale des infections alimentaires dans de nombreux pays, le problème est posé du risque pour la santé publique dû à des sérovars de Vet. Res. 32 (2001) 285-290 285

Using In Vitro Dynamic Models To Evaluate Fluoroquinolone Activity against Emergence of Resistant Salmonella enterica Serovar Typhimurium

“…Similarly, previous studies had also indicated that while field isolates or in vivo-selected mutants show small fold increases in MICs and often a single gyrA mutation, S. Typhimurium experimental mutants selected in vitro possess severalfold increases in MIC and multiple resistance mechanisms (25)(26)(27). In Salmonella, single gyrA mutations, in either S83F or D87Y, were associated with FQ-resistant isolates from humans and animals (10)(11)(12). Moreover, all field isolates harbored a single gyrA mutation of D87Y, which shows a lower MIC than mutation of S83F, while in vitro-selected resistance had an S83F mutation.…”

“…We chose to investigate S. Typhimurium because of its zoonotic significance and the high level of drug resistance reported for this organism across the globe (10)(11)(12). Loss of susceptibility in laboratory and field S. Typhimurium isolates was associated with inappropriate use of fluoroquinolones (12).…”

“…We chose to investigate S. Typhimurium because of its zoonotic significance and the high level of drug resistance reported for this organism across the globe (10)(11)(12). Loss of susceptibility in laboratory and field S. Typhimurium isolates was associated with inappropriate use of fluoroquinolones (12). We investigated veterinary fluoroquinolones, including difloxacin (DIF), enrofloxacin (ENR), and marbofloxacin (MAR), for two reasons: first, the risk of cross-resistance for fluoroquinolones has been reported for both human and animal pathogens (3,4,(13)(14)(15), and second, previous studies have demonstrated differences among veterinary fluoroquinolones in their activity and potential for selection of resistant mutants of bacteria (16).…”

Use of antimicrobials in veterinary medicine and mechanisms of resistance

“…Enzymatic inactivation has not been observed so far. The molecular basis and epidemiology of quinolone resistance in E. coli and Salmonella was reviewed by Cloeckaert and Chaslus-Dancla [16], Webber and Piddock [73] and Bager and Helmuth [4], respectively.…”

The Role of Proteomics in Elucidating Multiple Antibiotic Resistance in Salmonella and in Novel Antibacterial Discovery

“…Hence, the increasing antimicrobial resistance is considered a public health problem at a global level (Musgrove et al, 2006;Võ, 2007). A diversity of foods and environmental sources harbor bacteria that are resistant to antimicrobial drugs used in medicine and in food-animal production (Bager & Helmuth, 2001;Schroeder et al, 2004). Also the misuse and/or excessive use of antibiotics in human and veterinary medicine are in certain cases responsible for the increase and spread of resistance seen among the bacterial population.…”