Occurrence and distribution of multiple antibiotic-resistant bacteria of Enterobacteriaceae family in waters of Veraval coast, India

Current investigation was aimed to the assess occurrence and distribution of multiple antibiotic-resistant bacteria of the Enterobacteriaceae family in surface and bottom waters along the Veraval coast. Comparative prevalence of drug-resistance pattern among the isolates was determined using a battery of antibiotics. Fecal coliforms, Escherichia coli, Enterobacter spp., Salmonella spp. and Klebsiella spp. were isolated on specific media and tested for their resistance to specific antibiotics commonly used for treating human infections. Antibiotic resistance of bacteria was determined by the disc diffusion method. Of 235 isolates, 99 fecal coliforms, 30 Escherichia coli, 43 Enterobacter spp., 56 Klebsiella spp., and seven Salmonella spp. were examined. Multiple resistance, i.e. resistance to more than two antibiotics, occurred in almost 100% of Enterobacter spp., 86.8 % of fecal coliforms, 85.7% of Klebsiella spp., 56.6% of Escherichia coli, and 42.8% of Salmonella spp. In total, 97% of the isolates exhibited multi drug resistance character and all the isolates had a very high multiple antibiotic-resistance index, suggesting the origin of the isolates to be of high antibiotic usage. Antibiotic resistance indices were found to be highest for Enterobacter spp. and lowest for Salmonella spp. The study revealed that imprudent use of antibiotics in humans, aquaculture, poultry and livestock may pose high ecological risk to the Veraval coastal waters. There is a need to control anthropogenic activities in coastal water bodies to avert the occurrence of multiple antibiotic resistant bacteria.