Antibiotic Resistance Pattern of Bacteria Isolated from Pipe-Borne Chlorinated (Treated) Water and Untreated Water in Ilorin

Abstract

The antibiotic resistance pattern of bacteria isolated from chlorinated (treated) and untreated water was assessed with a view to ascertain the effectiveness of the quality of water employed in the city. Water samples were collected from taps, bore–hole, well and stream. A total of seven (7) bacterial species were isolated from the various samples analysed, the bacteria isolated are Staphylococcus aureus, Enterobacter aerogenes, Escherichia coli, Pseudomonas aeroginos, Bacillus subtilis, Klebsiella pneumonia and Streptococcus faecalis, Heterotrophic plate count (HPC), ranged from 0.5×104cfu/ml to 6.6×109cfu/ml, total enteric bacterial count ranged from 0.3×104cfu/ml to 2.1×109cfu/ml and total coli form count using the most probable number (MPN) ranged from 0 to 1.8×103cfu/100ml. Untreated water recorded the higher HPC, enteric bacteria count and MPN than treated water. The pH values ranged from 5.07–7.04, temperature ranged from 20.3°C to 24.3°C, turbidity ranged from 0.251 NTU to 0.846 NTU (Nephelometric Turbidity Unit), free residual chlorine ranged from 0.1mg/l to 0.9mg/l, chloride ion concentration ranged from 2.70mg/l to 11.20mg/l, sulphate ion concentration ranged from 0.87mg/l to5.14mg/l and nitrate concentration ranged from 1.04mg/l to 1.43mg/l. Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus had 75% occurrence, while Klebsiella pneumonia and Streptococcus faecalis had the least occurrence of 25%. The isolates were resistant to different antibiotics. All the microorganisms isolated were susceptible to ofloxacin and augmentin. This study demonstrates that though chlorine is a bactericide, it does not destroy all bacteria unless it is given under suitable conditions and that bacteria exhibit a high level of resistance to antibiotics