Survival and growth of Vibrio cholerae and Escherichia coli in treated groundwater consumed in northern Cameroon

Abstract

Treated groundwater is a major source of drinking water but subject to potential contamination of fecal–oral pathogens. To understand ecology of the pathogens in the treated water, this study evaluated survival and growth of Vibrio cholerae and Escherichia coli in the treated groundwater in northern Cameroon. E. coli and V. cholerae O1 were isolated from human feces. Water samples were collected from the following sources: a well, tap water from the Cameroon Water Utilities Company, and mineral and borehole waters sold in Maroua, respectively. These waters were treated by one or more processes, including autoclaving, filtration, chlorination and ozonation and were used for the constitution of microcosms. E. coli and V. cholerae were inoculated into each microcosm at respective concentrations of 50 CFU/10 mL (separately) and 40 CFU/10 mL each (together). All bacterial strains survived in all microcosms were used. The ability to survive and grow varied with the bacterial strain and microcosm (P < 0.05). When inoculated separately into the same type of microcosms, V. cholerae grew faster than E. coli with the latter even showing decrease in concentration in mineral water. When inoculated together, V. cholerae grew faster than E. coli, except in autoclaved well water and filtered and autoclaved well water. Autochthonous ultramicroflora inhibited the growth of E. coli in filtered well water (P < 0.05).

Occurrence of waterborne pathogens and antibiotic resistance in water supply systems in a small town in Mozambique

“…11% of the treated water samples were positive for V. cholerae and Campylobacter , while the two pathogens were detected in 18% and 15% of tap water samples, respectively, in absence of E. coli . V. cholerae survives better in estuarine waters than E. coli resulting in poor correlation of V. cholerae levels with fecal coliform concentrations in estuarine waters [ 49 ]. Also, V. cholerae non-O1 is a natural inhabitant of waters and therefore it may have a greater fitness in water than the enteric commensal E. coli .…”

Inactivation kinetics of selected pathogenic and non-pathogenic bacteria by aqueous ozone to validate minimum usage in purified water

“…Purified water is often made from public sources of drinking water. If pathogenic and nonpathogenic microorganisms, originating from these public sources, find their way to purified water, they may survive or even grow in this environment ( Warburton et al, 1998 ; McAlister et al, 2002 ; Djaouda et al, 2020 ). Additionally, contaminates may gain entrance during bottling, which is typically a non-aseptic process, or be present in bottles or caps prior to filling, particularly if bottles are formed outside the bottling plant and need to be shipped in for filling ( Ramalho et al, 2001 ).…”