Prevalence and Multidrug Resistance of Vibrio furnissii in Hand-Dug Wells Near Septic Tanks in Two Suburban Lagos, Nigeria

Access to safe drinking water is key to achieving appreciable gain in human health, which is a focus of the sustainable development goals (SDGs) and One health; hence well water meant for consumption must meet the quality guidelines for drinking water to reduce possible health-risk associated with chemical hazard and pathogenic microorganisms such as Vibrio species. Water samples from thirty hand-dug wells sited close to septic tanks in Ojo and Badagry areas of Lagos, Nigeria were examined for the prevalence of Vibrio species using membrane filtration techniques on Thiosulfate-Citrate-Bile-Salt Sucrose (TCBS) agar after enrichment in Alkaline Peptone Water, and the Vibrio isolates were evaluated for multidrug resistance using disc diffusion method and their plasmid profile assayed. A total of one hundred and thirty-one (131) strains belonging to five (5) species of Vibrio were obtained. Vibrio furnissii strains (58;44.3%) were the most prevalent, they were found in twenty-three (23) of the wells. Other Vibrio species isolated were Vibrio vulnificus (24;18.3%), Vibrio harveyi (15;11.5%), Vibrio anguillarum (12;9.2%), Vibrio parahaemolyticus (6;4.6%), Vibrio mimicus (12;9.2%) Vibrio cholera (4;3.1%). Vibrio. anguillarum and Vibrio. parahaemolyticus were found in only one well each. Thirty-two (55.17%) of the Vibrio furnissii were resistant to three or more classes of antibiotics (multi-drug resistant – penicillin, cephalosporin, chloramphenicol, cotrimoxazole). Eleven (34.4%) of multi-drug resistant Vibrio furnissii possessed plasmid with molecular weight varying between 690 kbp and 974 kbp. Contamination of the studied well water by species of Vibrio is clearly evident, this can be linked to the generally unhygienic state of the catchments of the wells. Also, detection of multidrug resistance in Vibrio furnissii portend possible difficulty in managing infection that may result. This requires urgent intervention; especially point of use interventions such as use of hypochlorite or boiling, to ensure the communities have access to safe drinking water.