|Title:||The Prevalence and Antimicrobial Responses of Yersinia Isolates in Comparison to Enteropathogens Causing Diarrhoea|
|???metadata.dc.contributor.*???:||Dr. Aberra Geyid|
|Publisher:||Addis Ababa University|
|Abstract:||Among the stool samples of 205 patients tested for bacteriological cultures, only 6 (2.9%) were positive for Yersinia, 22 (10.7%) for Salmonella, 12 (5.8%) for Shigella and 11 (42.3%) for diarrhoeagenic E. coli. Out of the Yersinia spp. totally isolated in this study, only 3 (1.5%) were Yersinia enterocolitica and 3 (1.5%) were Yersi11ia pestis. Among Yersinia enterocolitica strains two were isolated from children while one was from adult diarrhoeal patients. Similarly, 2 of these strains were from male patients, while I was from female patients. With regard to Yersinia pestis all strains were isolated from males, of which 2 were from children and one from adult diarrhoeal patient. The standardized agar disk-diffusion technique was used with disks of 13 antmicrobial agents (ampicillin, carbenicillin, cephalothins, chloramphenicol, gentamycin, kanamycin, nalidixic acid, norfloxacin, polymyxin B, streptomycin, sulphadiazene, tetracycline, and trimethoprim-sulphamethoxazole. All (51) strains of enteric pathogenic bacterial isolates were sensitive to nalidixic acid, norfloxacin, and polymyxin B and 46 strains were resistant to cephalothin. Sensitivity to gentamycin, nalidixic acid, norfloxacin and polymyxin B is greater than 90% of the tested strains, while resistance to cephalothin, ampicillin and tetracycline was greater than 50%. All strains of Yersinia enterocolitica and Yersinia pestis were sensitive to carbenicillin, chloramphenicol, gentamycin, kanamycin, nalidixic acid, norfloxacin, polymyxin B, streptomycin, sulphadiazene and trimethoprim-sulphamethoxazole. All strains of Yersinia enterocolitica were resistant to ampicillijn. Among Yersinia pestis strains, 66.7% were resistant to ampicillin and cephalothin respectively while 33.3% of the strains were resistant to tetracycline. Out of 22 Salmonella strains, all isolates were sensitive to norfloxacin, polymyxin B and nalidixic acid while 21 (95.5%) of strains were sensitive to gentamycin and kanamycin. Resistance was found 86.4% against cephalothin, 36.4% ampicillin and 27.0% sulphadiazene and both streptomycin and trimethoprim-sulphamethoxazole in 22. 7% of these strains. Eleven different combinations of resistant patterns were observed for all the Salmonella strains. All of the 12 strains of Shigella were sensitve to nadixic acid, norfloxacin, polymyxin B, gentamycin and kanamycin. Ampicillin, carbenicillin, cephalothin, streptomycin, sulphadiazene, tetracycline and trimethoprim-sulphamethoxazole were sensitive against ≤ 50% of Shigella isolates. Among the isolates, 91.7% were resistant against tetracycline, 50% against cephlothin, 75% against each of ampicillin and strepomycin. Totally, 10 different patterns of resistance were noted for Shigella spp. All strains of diarrhoeagenic E. coli were sensitive to gentamycin, kanamycin, nalidixic acid, norfloxacin and polymyxin B. While 90.9% of them were sensitive to chloramphenicol. Of all these isolates, 81.8% strains were resistant against cephalothin and 63. 6% against sulphadiazene. Based on the above summarized results the prevalence and antimicrobial response of Yersinia spp. is discussed in comparison with those of Salmonella, Shigella and E. coli isolates. According to this study, gentamycin, kanamycin, nalidixic acid, norfloxacin and polymyxin B were effective to treat diarrhoeal patients against enteropathogens.|
|Description:||A Thesis Submitted to the School of Graduate Studies in Partial Fulfillment of the Award of Master of Science in Applied Microbiology, Addis Ababa University|
|Appears in Collections:||Thesis - Biology|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.