Professor of Biology Joan Slonczewski and their Experimental Microbiology (BIOL 239) students are making strides toward more accurate COVID-19 wastewater testing at Kenyon and in Gambier. Slonczewski, who is also the chair of the Wastewater Testing Subcommittee of the Public Health Working Group, analyzes the raw data and publishes it to the Kenyon website in the Gambier Wastewater Virus Report, while their students tackle a more in-depth analysis of the data.
Because of Slonczewski’s expertise in metagenomic analysis, the study of genetic material recovered from environmental samples, they are in charge of conducting the wastewater analysis. They find the amount of virus particles per Kenyon manhole, as well as in Gambier.
Because the virus is so new, testing is not entirely accurate. According to Slonczewski, individual testing misses 30% of cases and wastewater testing misses 30 to 50% of all cases, so utilizing both methods is the best way to get as accurate as possible.
According to Slonczewski, the data has proven useful, especially when clinical testing is not enough. There has also been evidence of a strong correlation between virus shedding in the wastewater and infections: For the first three weeks of testing this semester, every spike in a manhole was associated with at least one infected person who had received a positive EverlyWell test. Because of this, the College is now using the wastewater data to pinpoint possible areas of infection around campus.
Slonczewski has to post their analysis as quickly as possible, so they do not account for extra variables. “There are three or four things that could be used to refine the signal and make better predictions, but I don’t have time to do that right now,” said Slonczewski. These include monitoring the total human waste in the wastewater and the percent efficiency of detection.
The students in their Experimental Microbiology lab can work on more detailed studies without such an intense time crunch. “I have my students doing a more complex analysis with the idea that maybe they will come up with a better way to analyze and perhaps give us more accurate predictions,” said Slonczewski. Although their primary analysis is the one getting published, the students’ work will hopefully refine the process.
Laura Grosh ’21, a student in the course, said the aim for the class’ analysis is to provide context and make sense of the raw RNA samples. “For example, we used levels of a virus found in peppers to normalize the COVID-19 RNA concentrations to human waste content,” she explained in a message to the Collegian. “Because enough people eat peppers, using this pepper virus is a good proxy for how much human waste is represented by a sample.”
Grosh was careful to note, however, that this is not a perfect science. “A major point of the lab was that all of the methods we’re using to analyze data have limitations,” she said. “That’s why we did multiple analyses and then can compare them.”
Grosh is glad she and her classmates are able to gain a deeper understanding of the wastewater project. “It feels like it’s science that actually impacts policy decisions and the real world and our world at Kenyon,” she said.
Back in June, Kenyon became the first college in Ohio to publicly provide data on the levels of COVID-19 virus in the wastewater. At first, the only source tested was the water in the Village of Gambier, which encompasses Kenyon. In January, the College increased the wastewater tested by taking samples from manholes on campus, paid for by the Ohio Water Resources Center (WRC). Kenyon was one of several Ohio colleges that received a $100,000 grant from WRC to use for testing and identifying virus sequences from the wastewater in campus sewage systems.
Wastewater samples are obtained either by the Gambier Wastewater plant manager or by Kenyon maintenance plumbers. Those samples then get shipped to LumenUltra, a commercial microbial monitoring laboratory in Miami. The lab identifies the viral sequences in the wastewater and sends the data back to Kenyon. Slonczewski then interprets the data and posts the report.
Slonczewski hopes to streamline this process by eventually handling sampling and analysis in Kenyon laboratories. It can take several days to get the information back from LumenUltra, so the College is working on obtaining the right equipment and a safe space for testing in order to minimize turnaround time. This would also allow for students to take a more involved role in the process. For now, Slonczewski is satisfied with the direction the College is headed. “It’s remarkable that we’re doing as well as this,” they said.