The prevalence of bacterial contamination in donated blood in Dar es salaam, Tanzania

Introduction: Blood transfusion services are required to provide blood and components which are safe in cost effective way for transfusion into patients who require the blood products. Study objective: This study aims to determine the prevalence of bacterial contamination and the antimicrobial resistance pattern in collected blood in Eastern zone blood transfusion centre. Methodology: A cross-sectional study was conducted at Eastern Zone Blood Transfusion Services located at Mchikichini, Ilala District, in Dar es Salaam. Stored whole blood bags were selected from the refrigerator containing 500 blood bags using a simple random sampling technique. About 384 blood bags were randomly picked for study, each blood bag was given an ID number (1-500), and a table of random numbers was used to select the 384 donated blood bags. Culture was done on different media; isolates were identified using standard biochemical and bacteriological methods. Kirby- Bauer disk diffusion method was used for antimicrobial susceptibility testing according to existing guidelines of CLSI. Data entry and analysis were performed using EpiInfo 3.5.1. Results: About 11 (2.8%) were found to have bacterial contamination, of which 9 (2.3%) were gram positive cocci and 2 (0.5%) gram positive rods. The bacterial isolates were about 7 (63.6%) coagulase negative staphylococci identified as Staphylococcus epidermidis and 2 (18.2%) were micro cocci identified as M.luteus and bacilli species identified as Corynebacterium diphtheroids. Sensitivity among the organisms were varied; as all the 11 (100%) of the organisms isolated were sensitive to amikacin, of which 7 (100%) Staphylococcus epidermidis were sensitive to ciprofloxacin, gentamycine, cefriaxone, erythromycin and co-trimoxazole. Gram positive rods were tested against erythromycin and Gentamycine; where 100% were sensitive to Gentamycine and (60.5%) were sensitive to erythromycin. M.luteus were tested against ceftriaxone and gentamycin had (98%) and (97.5%) sensitivity to these antibiotics respectively. Gram positive rods showed (100%) resistant to ampicilin, cotrimoxazole and tetracycline Conclussion: The isolates obtained in the donated blood are skin associated organisms and are considered as contaminants related to procedure during donor bleeding or taking sample for culture