Quantification of multiple waterborne pathogens in drinking water, drainage channels, and surface water in Kampala, Uganda, during seasonal variation

Abstract

Longitudinal water quality monitoring is important for understanding seasonal variations in water quality, waterborne disease transmission, and future implications for climate change and public health. In this study, microfluidic quantitative polymerase chain reaction (MFQPCR) was used to quantify genes from pathogens commonly associated with human intestinal infections in water collected from protected springs, a public tap, drainage channels, and surface water in Kampala, Uganda, from November 2014 to May 2015. The differences in relative abundance of genes during the wet and dry seasons were also assessed. All water sources tested contained multiple genes from pathogenic microorganisms, with drainage channels and surface waters containing a higher abundance of genes as compared to protected spring and the public tap water. Genes detected represented the presence of enterohemorrhagic Escherichia coli, Shigella spp., Salmonella spp., Vibrio cholerae, and enterovirus. There was an increased presence of pathogenic genes in drainage channels during the wet season when compared to the dry season. In contrast, surface water and drinking water sources contained little seasonal variation in the quantity of microbes assayed. These results suggest that individual water source types respond uniquely to seasonal variability and that human interaction with contaminated drainage waters, rather than direct ingestion of contaminated water, may be a more important contributor to waterborne disease transmission. Furthermore, future work in monitoring seasonal variations in water quality should focus on understanding the baseline influences of any one particular water source given their unique complexities.

Understanding the Impacts of Short‐Term Climate Variability on Drinking Water Source Quality: Observations From Three Distinct Climatic Regions in Tanzania

“…The other studies were unable to explicitly quantify the impact of rainfall variation on water quality. Specifically, Taylor et al () visually examined the temporal trends in high‐frequency rainfall and water quality data, while Sadik et al () used significance tests to assess water quality differences between dry and wet periods. Therefore, it is difficult to predict water quality changes based on climate variability, which is a critical first step in making climate change projections for source water quality.…”

“…However, there are very few quantitative assessments on how source water quality may change with climate change. This is because there is not a wide understanding of even how water sources have historically responded to weather and climate variations (Howard et al, ; Levy et al, ; Sadik et al, ; Taylor et al, ; Wu et al, ). The main limitation of the existing studies is their limited spatial domain and, in some cases, the limited temporal sampling which hinders extrapolation of the results to a range of geographic and climate conditions.…”

The Effect of the 2015 Earthquake on the Bacterial Community Compositions in Water in Nepal

“…Samples in Kathmandu were collected directly from the well using the bucket provided and the samples in Jhapa were collected after a quick flush of 30 s. Samples were treated with 2.5 M MgCl 2 •6H 2 O (Sigma-Aldrich, St. Louis. MO) for 30 min to coagulate the microorganisms (Mattioli et al, 2013 ; Sadik et al, 2017 ). Next, coagulated water samples were vacuum-filtered through a 0.45 μm sterile cellulose acetate filter (GVS Maine, Sanford, ME) placed in 47 mm filtration funnel (Pall Corporation, New York, NY) for samples taken in 2014 (referred to as Batch 1 samples).…”

Detection of Diarrheagenic Pathogens in Improved Water Using PCR-Based Specific Techniques in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis Protocol

“…Genetic diversity of human enteric bacterial [1],viral [2][3][4]and protozoal genomes in water samples are becoming increasing and complicated as a result of contamination of improved water at the sources, collection and storage at home that creates increasing public health threats in low-and middle-income countries. The detection of human enteric viruses in drinking water con rms the quality limits for indicator bacteria that warrants an investigation of the potential transmission risk of infection constituted by different waterborne genomes of viruses [5,6]and protozoans [7].…”