Abstract
D.Tech. (Biomedical Technology)
Free-living amoebae (FLA) are unicellular organisms that can survive in soil, air and water, and mostly feed on bacteria. FLA have been isolated from natural environments, as well as man-made spaces. Amoeba-resistant bacteria (ARB) have adapted to not be digested by these amoebae, but rather increase in virulence before causing the amoebae to lyse, thereby escaping into the surrounds in increased numbers. FLA and ARB are made up of both pathogenic and non-pathogenic species. Some non-pathogenic species may, however, pose a health risk to immunocompromised individuals. The aim of this study was to investigate the microbiological quality of groundwater used by workers living in farming communities in two provinces in South Africa, with specific focus on the occurrence of free-living amoebae, amoeba-resistant bacteria, and other possible emerging bacteria. All collected water and biofilm samples were tested by using standard microbiological methods to determine genus and species, as well as their antibiotic-resistance profiles. Both 16S rRNA and 18S rRNA PCR and sequencing were used to confirm the organisms isolated. Seven informal settlements spread across two northerly provinces in South Africa were included in the study; of these areas, 85 households agreed to participate in the study. The participants would collect water each day (sometimes a few times per day) in a 20-litre plastic container from either a communal tap, fed by a borehole, a windpump, large Jo-Jo water tanks, or a borehole pump. With no municipal water supply, the area uses the groundwater collected for drinking, cooking and washing. Over a period of five months, water samples were taken from within the households. A sample of one litre was taken from the stored water in the house. After the intervention, which entailed five settlements receiving Potters for Peace...