The University of Missouri won’t be testing students at the front end as they arrive this week by jabbing a long swab into their nostrils to find out if they have COVID-19.


Instead, they will be testing them at the back end, by monitoring wastewater from residence halls for signs of the virus, then working to isolate which residence hall has infection and boxing in those who are contagious.


The novel monitoring program is an outgrowth of a project that has been checking samples from 71 wastewater systems, large and small, from around the state. After four weeks, the program has shown a lot of promise as a way to get an early warning that the coronavirus is circulating in a population.


"We will show it before people go to a clinic," said MU scientist Marc Johnson, who has been processing the samples with Chung-Ho Lin in their campus lab. "People put it into the wastewater before they think they are sick enough to go in and get checked."


At MU, where approximately 80% of students who live on campus are in dorms grouped together in four clusters, a sample will be taken from the common sewage outfall from each cluster, said Johnson, a professor of microbiology and immunology. A portion from each sample will be pooled into a single lab run where the RNA proteins are separated and checked for evidence of the virus.


If the pooled sample is positive, the individual samples will be tested.


"How you respond to a positive is the part that has everyone really scratching their heads," Johnson said.


The wastewater monitoring research is a cooperative effort of the Department of Natural Resources, which has the infrastructure for collecting the samples, and the Department of Health and Senior Services, which is looking for ways to identify where the virus is spreading. It is being funded by a Centers for Disease Control and Prevention grant through the state health department.


Johnson is doing the analysis because his laboratory can isolate the samples so they don’t infect people as they are manipulated.


"There is a certain amount of biocontainment required for raw sewage," Johnson said. "There is no evidence there is infective COVID in the wastewater, but there is a lot of other nasty stuff in there."


THE IDEA


The discovery that people who contract the coronavirus shed it in quantities easily detectable in wastewater was made in the Netherlands and several other countries.


Johnson credits the idea of applying it in Missouri to Chris Wieberg, director of the Missouri Water Protection Program.


"There are a lot of things that the public uses that are not water soluble that you can pick up in wastewater," Wieberg said in an interview.


Caffeine is one example, and so are many pharmaceuticals.


"If you wanted to evaluate those concentrates in a population, the sewer system, or a sewer shed, is a way of doing that," he said.


One goal for the research is to understand how different inputs into those sewer systems change the effluent. A large industrial water user can supply a large portion of a community’s wastewater. So can rainwater infiltrating into leaking sewers or, in some old systems, pouring into the wastewater as an overflow during heavy rains.


Wieberg’s program oversees 12,000 wastewater discharge permits.


"There can be unique or confounding factors," he said. "Not all sewer systems are created equal. The sewer systems in St. Louis are highly influenced by rainfall."


The things he’s finding in the wastewater besides the coronavirus is remarkable, Johnson said.


"When you talk about St. Louis, the stuff that goes into their wastewater, you could write a novel on it," he said.


Johnson’s lab is running the fifth week of samples for the project. It is showing some tantalizing results, said Jeff Wenzel, health department bureau chief for the Bureau of Environmental Epidemiology.


"What we are seeing and what CDC is reporting is that sewer shed has its best correlation at five days prior to onset of symptoms, meaning that theoretically, we could see a new outbreak five days prior to human testing," Wenzel said.


Each system being monitored uses an auto-sampler so the water being tested was collected over a period of time. The samples are coming from some of Missouri’s largest systems and some of the smallest. There are two Department of Mental Health facilities in the program and three state prisons, with the results reported to the agencies after analysis.


The analysis for each system is going through its "growing pains," Wenzel said.


For communities that have low counts, the analysis can show increased presence of the virus before clinical cases are reported, he said. It will be more difficult to detect new outbreaks in locations that already have a high past incidence of the coronavirus.


"The downside is that individuals continue to shed genetic material beyond when they are symptomatic," Wenzel said. "The benefit really is going to be looking at those new outbreaks. The downside is we are not going to be very good at telling when an outbreak is over."


THE APPLICATION


Taking samples from MU residence hall outflows should provide a controlled look at how and when the coronavirus appears in wastewater. There shouldn’t be any of the RNA proteins from the virus before empty dorms are populated.


The more limited the population using a system, the more effective monitoring will be in identifying new outbreaks and where testing and medical resources should be prepared, Wenzel said.


"When you are measuring the entire community, we are not able to look at a specific block or neighborhood to narrow that in," he said. "And to complicate that is, a question can arise whether it is a visitor coming through that stays for a couple of days or is it someone local to be tested?"


And obtaining results requires specialized equipment needed to extract the RNA proteins, similar to what is done when individual tests are determined to be positive or negative. That means that automatic monitoring of congregate facilities like jails and care facilities is not possible, and regular monitoring would require significant lab resources, Wenzel said.


The state’s effort is to see if it is possible, Wenzel said.


"There are private labs that are starting and doing this type of testing," he said. "It is becoming more possible for a private entity to send a sample to a lab."


The bugs to be worked out, Johnson said, include determining why some wastewater samples show relatively low virus levels when it is clear from clinical testing that there are significant numbers of cases in a community.


But when the testing works as expected, it really works, Johnson said.


His lab has been analyzing samples sent daily from Boise, Idaho, for the past month. He watched it grow as the city eased restrictions on gatherings, from a few thousand copies per liter to more than 10,000 copies per liter.


Then it really spiked.


"It was five days into phase 4 and bars are open," Johnson said. "That was the first time I saw something over 1 million copies per liter and fell out of my seat."


That reading coincided with a period where Ada County, Idaho, was experiencing as many as 400 new cases per day.


Despite its growing pains, the program in Missouri has been able to offer early warnings in some instances, he said.


An effective application of the monitoring would be on congregate facilities like jails and long-term care facilities, where the population is limited, Johnson said.


But community monitoring can prepare health officials, Johnson said.


"When there is a spike, it means something," he said. "There have been several cases where we have seen a spike in wastewater and immediately go to the local health facility."


rkeller@columbiatribune.com


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