Determination of prevalence and antibiotic susceptibility pattern of the bacterial isolates collected from different parts of domestic refrigerators

Abstract

Refrigerator form an important link in wide chain of cross contamination which leads to the outbreak of domestic food borne disease.In this study samples were obtained from various parts (drawer,handle,egg tray,surface) of domestic refrigerators of various parts of Mohakhali and Mirpur area, Dhaka, Bangladesh. A total of 37 isolates collected from 8 different parts were identified. Identification of bacteria was done through conventional biochemical tests according to Bergey’s Manual of Systematic Bacteriology. Antibiotic susceptibility pattern of all isolates were performed against nine commercial antibiotic discs [Ampicillin (10 μg), Ciprofloxacin (5 μg), Chloramphenicol (30 μg), Gentamycin (10 μg), Azithromycin (15μg), Penicillin-G (10 μg), Nalidixic acid (30 μg), Streptomycin (10μg), Tetracycline (30 μg)] by using Kirby-Bauer disc diffusion method. A total of 37 isolates had been identified where Staphylococcus spp.and Klebsiella spp.showed the highest prevalence 8(21.62%), next to Pseudomonas spp 5(13.5%).,E.coli 5(13.5%), Salmonella spp 5 (13.5%), Bacillus spp. 2 (5.4%) and Vibrio spp. 4 (10.8%). Ampicillin showed the highest resistance percentage (81.08%) for most of the isolates. Out of 37 bacterial isolates, (29.72%) were resistant to more than two antibiotics. We also determined temperature tolerance of the organisms by growing the isolates in different temperature like 45°C,50°C and 55°C. All the isolates showed growth at 45°C but in 50°C and 55°C only (54.05%) and (10.81%) isolates showed viable growth. These results indicate that the presence of these organisms, including potential foodborne pathogens, in domestic refrigerators portends serious health implications. It is needed to maintain appropriate food storage and refrigerator management, and proper hand hygiene is recommended.