Co-Existence of Free-Living Amoebae and Potential Human Pathogenic Bacteria Isolated from Rural Household Water Storage Containers

Abstract

This study investigated the co-existence of potential human pathogenic bacteria and free-living amoebae in samples collected from stored water in rural households in South Africa using borehole water as a primary water source. Over a period of 5 months, a total of 398 stored water and 392 biofilm samples were collected and assessed. Free-living amoebae were identified microscopically in 92.0% of the water samples and 89.8% of the biofilm samples. A further molecular identification using 18S rRNA sequencing identified Vermamoeba vermiformis, Entamoeba spp., Stenamoeba spp., Flamella spp., and Acanthamoeba spp. including Acanthamoeba genotype T4, which is known to be potentially harmful to humans. Targeted potential pathogenic bacteria were isolated from the water samples using standard culture methods and identified using 16S rRNA sequencing. Mycobacterium spp., Pseudomonas spp., Enterobacter spp., and other emerging opportunistic pathogens such as Stenotrophomonas maltophilia were identified. The results showed the importance of further studies to assess the health risk of free-living amoebae and potential human pathogenic bacteria to people living in rural communities who have no other option than to store water in their homes due to water shortages.

Extensive Cryptic Diversity and Ecological Associations Uncovered among Mexican and Global Collections of Naegleria and Vermamoeba Species by 18S Ribosomal DNA, Internal Transcribed Spacer, and Cytochrome Oxidase Subunit I Sequence Analysis

“…In contrast, the Naegleria isolates had a broad distribution in water and soil along the different natural ecosystems sampled ( Table 1 ). Our results are in line with several previous studies that analyzed the diversity of FLA in rivers ( 51 ), rural borehole water ( 75 ), drinking-water processing plants ( 53 , 76 ), domestic and clinical tap water distribution systems ( 54 , 77 – 79 ), public baths ( 56 ), and swimming pools ( 80 , 81 ). These publications report a high prevalence of V. vermiformis in these aquatic, mostly human-made ecosystems.…”

Waterborne parasites in Uganda: A survey in Queen Elizabeth Protected Area

“…This finding aligns with prior studies that have revealed a higher prevalence of the FLA in areas characterised by elevated levels of organic matter contamination [36][37][38]. Additionally, the formation of biofilms inside piped water systems is also major contribution in the survival and transmission of FLA [39][40][41].…”

Free-Living Amoeba Vermamoeba vermiformis Induces Allergic Airway Inflammation

“…Recent study has reported that Vermamoeba (Hartmannella) vermiformis as the etiological agent of an infection close to the eye of a female patient [5]. Some investigators checked localization of FLAs in our environments because they thought that FLA is a potential pathogen or vector of bacterial pathogens [33][34][35][36]. FLAs were detected with potential human pathogenic bacteria in stored water in rural households in South Africa [34].…”

“…Some investigators checked localization of FLAs in our environments because they thought that FLA is a potential pathogen or vector of bacterial pathogens [33][34][35][36]. FLAs were detected with potential human pathogenic bacteria in stored water in rural households in South Africa [34]. Several bacteria are ingested by FLAs and digested as a food source, whereas others have adapted to survive and grow within the amoebae by resisting against FLA, which are known as amoeba-resistant bacteria [2].…”