Detection of potential risk of wastewater effluents for transmission of antibiotic resistance from Vibrio species as a reservoir in a peri-urban community in South Africa

We assessed the antibiogram characteristics of some Vibrio species isolated from wastewater final effluents in a typical peri-urban community of South Africa. Marked resistances were noted against erythromycin (100%), chloramphenicol (100%), nitrofurantoin, cefuroxime and cephalothin (90-95%) in V. parahaemolyticus, V. fluvialis and V. vulnificus, respectively. Fourteen antibiotypes were identified, with multiresistance to 8-10 antibiotics being common. The antibiotypes AMP, PEN, STR, SUL, TMP, COT, CHL, ERY, CIP and PB demonstrated by V. fluvialis were the most prevalent (17.24%). Eight putative antibiotic resistance genes were identified with floR being the mostly (100%) detected in all the three species while tet(A) was the least with 65% prevalence in V. vulnificus, 7.14% in V. parahaemolyticus and none in V. fluvialis. These results demonstrate that the treated effluent system are reservoirs for various antibiotic resistance genes which could be disseminated to inhabitants downstream the plant and pose health risk to the communities who are dependent upon the watershed for domestic and recreational purposes.