Antimicrobial susceptibility pattern of Shigella isolates in Awassa

Abstract

A prospective study was conducted in Awassa, Southern Ethiopia from July 1997 to April 1998 in order to determine the antimicrobial pattern of Shigella strains. Moreover, the study was intended to form the basis of treatment guidelines for shigellosis appropriate to local conditions. In addition, the study was designed to accumulate epidemiological information on the resistance patterns of Shigella isolates of public health importance. A total of one hundred Shigella strains were isolated from 289 cultures received at the Center for Health Research and Laboratories (CHRL), collected from different health units. Ninety-nine strains were Shigella flexneri group B and one Shigella dysenteriae group A isolated. All isolates were susceptibility tested for nine antibiotics using disc diffusion technique. The result showed that 96% and 90% strains were susceptible to gentamicin and nalidixic acid respectively. High rate of resistance was particularly documented against the following antibiotics: ampicillin (93%), erythromycin (90%), and tetracycline (90%). Fifty-six percent of Shigella flexneri Group B isolates were found to be resistant to trimethoprim-sulfamethoxazole, which is one of the drugs of choice for treating shigellosis is Ethiopia. Multiple drug resistance to as many as six antibiotics, i.e. ampicillin, cephalotin, chloramphenicol, erythromycin, tetracycline and trimethoprim-sulfamethoxazole has been observed in this study. One strain of Shigella flexneri was found to be resistant to eight drugs. The findings are discussed and recommendations forwarded.


(Ethiopian Journal of Health Development, 2000, 14(2): 149-154)