Isolation, characterization and antibiotic resistance profile studies of bacteria from an excavated pond in Port Harcourt Metropolis, Nigeria

Abstract

The Antibiotic Resistance profile of bacteria isolated from Rumuola pond water in the Port Harcourt metropolis, Rivers State, Nigeria was investigated. Total of 48 bacterial species were isolated on Nutrient Agar and a set of selective diagnostic media. The isolates were identified as Escherichia coli, Staphylococcus sp.; Shigella sp.; Klebsiella sp.; Vibrio sp.; and Salmonella sp. The total culturable heterotrophic bacterial count (TCHB) and faecal coliform count of the water samples ranged from 1.02 x 10⁶ – 1.90 x 10⁶cfu/ml and 3.70x 10⁵ – 8.15x10⁵ cfu/ml respectively. The sensitivity of the isolates from the water samples to 12 different antibiotics selected was ascertained on Muller-Hinton agar using the Kirby-Bauer disc diffusion method. The zone diameter obtained was interpreted using the Clinical Laboratory Standard International (CLSI) and British Society for Antimicrobial Chemotherapy (BSAC) zone diameter breakpoints. Isolates were recorded as susceptible (S), intermediate susceptible (I) or resistant (R) based on the guidelines. The level of resistance exhibited by the isolates to specific antibiotics used were; Lincocin 74.8%, Rifampicin 71.4%, Augumentin 71.2%, Chloramphnicol 68.2%, Erythromycin 64.3%, Cotrimoxazole 55.8%, Streptomycin 50.2%, Pefloxacin 48.6%, Gentamycin 43%, Norfloxacin 42.9%, Ofloxacin 16.2%, Ciprofloxacin 13%. The resistance to Lincocin (74.8%) was the highest followed by Rifampicin (71.4%). The highest level of bacterial resistance pattern to all tested antibiotics was observed in sites with highest human activities. The result showed multiple antibiotic resistance patterns among the bacterial isolates suggesting a pool of resistance genes among isolates in the pond. Most of the bacterial isolates are potential pathogens. Modern health services for effective disease management for this community would include antibiotic/drug mapping for individuals.

Keywords: Antibiotic Resistance, Rumuola Pond, Port Harcourt