Prevalence and characterization of methicillin resistant staphylococcus spp. in surface water of Dhaka

Abstract

Dhaka city being the capital of Bangladesh faces problem with rapid urbanization based on ruralto- urban migration often results in the contamination of water bodies with bacteria pathogenic to humans. This study aims to determine the prevalence of environmental Staphylococcus spp. contamination in water with industrial wastes, specifically focusing on Staphylococcus aureus. A total of 35 water samples were collected from both Hatirjheel Lake and Buriganga River, representing Dhaka city’s water bodies. Then they were processed for isolation of cultureable Staphylococcus spp. strains. For this, the collected water samples were first plated on to Mannitol Salt Agar (MSA). One pure colony from each positive plate was then selected for further processing. Presumptive isolates were then confirmed using biochemical methods. To determine whether they are Staphylococcus aureus or not. After that hemolytic activity on the samples were observed by inoculating them on Blood Agar and it showed 100% hemolysis for isolates from Hatirjheel and 82.35% for those from Buriganga. For determining the virulent activity of the strains, coagulase test was done and 72.22% coagulase positive were observed for Hatirjheel-isolates and 71% Buriganga-isolates. Antibiotic susceptibility test showed similar results for Hatirjheel Lake and Buriganga River, except for methicillin-resistance. Resistance to methicillin was found in 5.56% of the Hatirjheel-isolates whereas 35.50% of the Burigangaisolates were MRSA. This study reveals that both Hatirjheel Lake and Buriganga River are contaminated with Staphylococcus spp.that may lead to serious health hazard in near future.