Mpala Waterborne Disease Project

Waterborne illnesses present a significant threat to the health of humans, animals, and the surrounding environment. According to a study titled, the intersection of land use and human behavior as risk factors for zoonotic pathogen exposure in Laikipia County, Kenya, “œIn Kenya, resource sharing, or common use of grazing and watering resources among humans and animals, is prevalent in pastoral communities and within arid and semi-arid land (ASAL) areas. Human interactions with domestic animals can increase risk of zoonosis transmission within communities that practice animal production, particularly via contact with infected food and water.” (Kamau et al., 2021). A study by Manetu & Karanjai in 2021 stated that infections can be acquired through untreated water sources while bathing, washing, drinking water, and eating foods exposed by contaminated water. This can result in several symptoms, with diarrhea and vomiting being the most common. According to the study titled Waterborne Disease Risk Factors and Intervention Practices, the Ministry of water and Irrigation report (2012), 50% of Kenya’s households did not have access to safe drinking water and the proportion for the poor households was higher. Most of the Kenyan rural populations obtain their water supplies from unprotected sources, underground water, streams, spring wells, ponds and lakes frequently resulting in diarrhea diseases” (Manetu & Karanja, 2021). Due to the lack of accessibility to safe drinking water, testing the water at the Mpala Research Centre at the 5 different sites would help to evaluate the various pathogens that may be present within the Mpala ecosystem. Additionally, this knowledge could assist in informed decision-making regarding wastewater treatment and could help prevent any future outbreaks of diseases in the Mpala and local communities.

Hello, my name is Nisa Berlas, my name is Peyton Beaumont, and I’m Nicole Brandt; and this is the Mpala Waterborne Disease Project. We spent 3 weeks at the Mpala Research Centre in Laikipia county, Kenya to conduct research on pathogens in the area that could impact the health of humans and wildlife in the surrounding environment. Our original plan was to research vector-borne pathogens, but then we learned about an ongoing diarrheal disease outbreak at Mpala. We decided our resources and time would be better spent investigating this outbreak in real-time to find the source of exposure. The objective of the Mpala Waterborne Disease Project was to isolate potential waterborne pathogens from different sources at the Mpala Research Centre and provide recommendations for preventing future disease exposure. Our group designed an original protocol to conduct an experiment with methods derived from similar research studies on wastewater collection. We collected twenty-eight samples from septic tanks and pit latrines around the campus, as well as water from communal sources such as sinks and showers. A nearby dam, which is the water source for Mpala, acts as a watering hole for local wildlife. Because this water is used by both humans and animals, it was also tested to determine any traces of pathogenic origin that could have caused a spillover event. By collecting and testing these water samples, we were able to determine the likely cause of the outbreak. We decided to collect our samples between 9am and 11am due to a recommendation from a previous study by Kevill et al. in 2022 that used similar wastewater collection methods. Next, we needed to figure out how long we would need to sample for, to gather adequate results. We decided two collection days were sufficient enough after several sample test runs of the tampon-dip method. Collection tubes were respectively labeled for wastewater, communal water, and dam water, along with positive and negative controls. We mapped out our collection sites with their corresponding coordinates to determine if location impacted which pathogens may be present. A cooler with ice packs and a tube rack were brought along as we moved from site to site to keep the samples viable. Using proper PPE listed in the protocol, a new tampon was tied to a string and lowered into the wastewater to collect a sample at each site. Once a minute had passed, the tampon was removed from the wastewater and liquid was extracted by squeezing it into a collection tube. Then, a sliver of the tampon was cut and placed into a tube to be homogenized later for PCR.
Between collection sites, new PPE was donned, and ethanol and bleach were used for surface decontamination. For communal water, a collection tube was brought to each site and the water source was run for 20 seconds prior to collection to wash away any stagnant impurities.
The dam water was collected during normal collection times and poured into a whirl-a-bag with approximately two cups of water from the upstream and downstream face of the dam. These steps were respectively repeated for each collection site for the two testing days. To process the field samples, we first used the Biomeme M1 Sample Prep to extract DNA from the collected water to obtain a purified sample. It includes a single-use syringe, binding column tip, and a cartridge with subsequent washes to obtain a purified sample upon elution. Each section of the cartridge has a recommended number of times the syringe must be pumped to mix the solution. Additionally, between each section the contents of the syringe must be expelled before insertion into the next section.
First, using a pipette the sample is transferred into the lysis and binding section of the cartridge, which breaks open the cells. This step was repeated for the protein and salt wash sections to remove any possible proteins and salts present. The syringe was then injected into the drying section of the cartridge where it was pumped rapidly to remove any remaining fluid. Lastly, the syringe was inserted into the elution step which is the process of extracting a substance that is absorbed to another by washing it with a solvent. As a result, the DNA has been isolated and is ready to be extracted and prepared for PCR.
In preparation for PCR, the sample was added to the Biomeme 3-welled Cave Panel B Go-Strips using a pipette. This is a small sterile strip with 3 wells that contains a lyophilized master mix in each well with primers, probes, and enzymes. Each well tests for 3 different waterborne diseases including Salmonella, Listeria, Legionella, Giardia, Campylobacter, E. coli, Cryptosporidium, and Human Fecal Matter (HF183) as the positive control. Additionally, our group used Phosphate- Buffered Saline (PBS) as the negative control to determine if there were any environmental contaminants present. After the sample was added to the Go- Strip, it was flicked several times to ensure there were no air bubbles present which could hinder the results. The Go- Strip is then inserted into the thermocycler machine to undergo PCR, which amplifies the DNA isolated from the Biomeme M1 Sample Prep to determine if there are any waterborne diseases present in the collected water. In a perfect experiment, a researcher wants as many variables as possible to be the same to yield the most accurate results. Unfortunately, there are always some limitations with field work as there are many variables that may be impossible to control. For example, two of the sites that we collected from were open to environmental contaminants, which could have impacted the pathogens found at those locations. Additionally, the tampon saturation varied between testing locations due to the differing characteristics of each site. For instance, when we tested the pit latrines, our tampons did not get fully saturated as the pit latrines did not contain much liquid waste. Another limitation was our sample size, as a larger sample size could have yielded more accurate results. However, on account of our limited time at Mpala Research Centre, as well as resource sharing with other projects, we were unable to collect as many samples as we had initially hoped. Our experiment yielded positive results for diarrheal diseases, however, we will not be disclosing which specific pathogens were found due to privacy reasons. Our research was conducted to help the Mpala Research Centre find the source of exposure so they could make an informed decision about what steps could be taken to prevent future outbreaks. It was determined that the likely source of the pathogen was the dam water that wildlife often uses as a watering hole. While this water is filtered before it gets to Mpala, some pathogens are able to pass through the filter, likely contributing to waterborne disease outbreaks. Because of our research, a fence is being built around the dam to prevent disease spillover from wildlife, and a representative from Mpala will be testing the water on a monthly basis. As a result of our findings, we suggest that any future diarrheal outbreaks be treated with antiparasitics rather than antibiotics. If you would like more details on our research methods, a link to the protocol we wrote will be included at the end of this presentation along with our sources. Overall, this was a great opportunity which helped us start our introductive journey into academic research and helped build our critical thinking skills in terms of developing our own scientific protocol. We were also able to have a positive impact, as our research led to the creation of protective measures to prevent future waterborne disease outbreaks. We would like to thank the OSCAR office, Dr. Michael Von Fricken, and the Mpala Research Centre for making this project possible. We can’t wait to continue our research in the future.