ABSTRACT
Salmonellosis is an important public health problem, particularly in lower income countries including Yemen. The emerging of antimicrobial resistant Salmonella is the commonly encountered world wide. This a cross-sectional study was conducted to determine the susceptibility to nalidixic acid and ciprofloxacin of non-typhoidal Salmonella serogroups isolated from fecal samples of patients having diarrhoeal illness who visitted National Center of Public Health Laboratories in Yemen for the period from August 2003-to November 2005. Non-typhoidal Salmonella were isolated from fecal samples and inoculated on suitable media, on the basis of microbiological examination, cultural characters, biochemical tests, antimicrobial sensitivity test [disc diffusion], and serogrouped with commercial antisera were done for isolates. Out of 406 isolated strains, there were 184 of isolates were resistant to common antimicrobial agents, and the most frequently serogroup identified resistant strains in this study were serogroups B [23.4%], followed by serogroups C [12.8%], and D [6.4%] respectively. The isolated strains were tested against a number of antimicrobial agents including two quinolones: nalidixic acid, and ciprofloxacin. Emerging quinolone resistance was detected of all non-typhoidal Salmonella isolates tested, 35 [8.6%] were resistant to nalidixic acid, and only three [0.7%] of them with resistant to nalidixic acid were also resistant to ciprofloxacin. It clear from the present study that, the resistance of nalidixic acid has increased from 5.6% [2003] to 10.8% [2005]. The MIC to nalidixic acid and ciprofloxacin were 128 micro g /ml and 4-8 micro g/ml respectively. These findings reveal that very few non-typhiodal isolates of Salmonella in Yemen that are resistant to nalidixic acid are also resistant to ciprofloxacin. Continued surveillance for quinolone resistant Salmonella is necessary, particularly after recent approval of a fluorquinolone for use animals intended for food in many regions of the world