Transferable antibiotic resistance among thermotolerant coliforms from rural drinking water in India

A total of 231 thermotolerant coliforms was isolated from rural drinking water from four states of India. Of these, 220 isolates were resistant to ampicillin, chloramphemicol, streptomycin and tetracycline. Multiple (MAR), double and single antibiotic resistances were observed in 31.4, 48.6 and 13.7% of the isolates, respectively. Out of 177 antibiotic-resistant isolates examined for transmissibility, only 15.3% were able to transfer their resistances to Escherichia coli K-12 recipient. The resistances were transferred by 32.5% of MAR, 21.9% of double resistant and 7.6% of single resistant isolates. Ampicillin resistance was transferable in 14.69% strains while resistances for the rest of the antibiotics were transferable in less than 4% strains. MAR strains of E. coli and Klebsiella sp. showed highest levels of R-plasmid transfer.