Detection of Free-Living Amoebae and Their Intracellular Bacteria in Borehole Water before and after a Ceramic Pot Filter Point-of-Use Intervention in Rural Communities in South Africa

Abstract

Free-living amoebae (FLA) are ubiquitous in nature, whereas amoeba-resistant bacteria (ARB) have evolved virulent mechanisms that allow them to resist FLA digestion mechanisms and survive inside the amoeba during hostile environmental conditions. This study assessed the prevalence of FLA and ARB species in borehole water before and after a ceramic point-of-use intervention in rural households. A total of 529 water samples were collected over a five-month period from 82 households. All water samples were subjected to amoebal enrichment, bacterial isolation on selective media, and molecular identification using 16S PCR/sequencing to determine ARB species and 18S rRNA PCR/sequencing to determine FLA species present in the water samples before and after the ceramic pot intervention. Several FLA species including Acanthamoeba spp. and Mycobacterium spp. were isolated. The ceramic pot filter removed many of these microorganisms from the borehole water. However, design flaws could have been responsible for some FLA and ARB detected in the filtered water. FLA and their associated ARB are ubiquitous in borehole water, and some of these species might be potentially harmful and a health risk to vulnerable individuals. There is a need to do more investigations into the health risk of these organisms after point-of-use treatment.

Clinical Improvement of Disseminated Acanthamoeba Infection in a Patient with Advanced HIV Using a Non-Miltefosine-Based Treatment Regimen in a Low-Resource Setting

“…The distribution of Acanthamoeba spp. in South Africa has been described in zoological and environmental sampling studies [5][6][7], but the prevalence of opportunistic infections due to Acanthamoeba spp. in South Africa is largely unknown, as the only published clinical reports describe cases of amoebic keratitis [8,9].…”