The Next Step Of NIU's COVID-19 Surveillance Testing Lies In Wastewater

Oct 20, 2020

Northern Illinois University is expanding COVID-19 testing efforts into what some might consider an unexpected place: wastewater.

Dr. Barrie Bode was the longtime chair of NIU’s Department of Biological Studies. Now he has a new title he could have never anticipated: director of COVID-19 facilities.

Partnered with the Kishwaukee Water Reclamation District, Bode is building a lab and assembling a team to implement a new component in the university’s surveillance testing plan.

“Wastewater testing is literally taking samples of wastewater from different access points. And assay the wastewater for the presence of the SARS-CoV-2 virus,” he said.

Those “access points” are mostly residence halls, as well as neighborhoods around the university where a lot of students live.

Bode says initial reports show the virus is traceable in the stool of around one-third to one-half of infected people even before they show symptoms. Studies show it might persist in their system for weeks. The idea is to monitor high-risk areas like dorms for spikes in COVID concentration and catch outbreaks before they happen.

“You can then refocus your other testing resources on subjects that may either live in that residence hall or in that neighborhood,” he said.

So far, Bode says the results at other colleges have been promising. The University of Arizona credited wastewater testing for preventing the virus from spreading in its dorms back in August.

NIU has avoided an outbreak of COVID-19 so far. Positive cases peaked in September and have been down since. But, the university is in Region 1 of the state’s reopening plan, where the positivity rate recently topped 10%.

And Illinois and surrounding states continue to struggle with both the number of cases and deaths due to the virus.

Wastewater testing isn’t limited to college environments. Spain and Italy, among other countries, have invested in similar programs for entire cities.

At NIU, Bode’s lab is hoping to be in a process development phase by November. They’ll then be ready to test wastewater streams on campus and in the surrounding community by next semester.

Bode says it takes a lot of steps to process a sample once it gets to the lab.

“Wastewater, as you can imagine, is a very complex medium to try to measure things in, as opposed to say, a nasal swab or saliva,” he said.

A range of factors come into play even depending on where the wastewater is taken from.

“Sewer lines contain a mixture of a lot of things,” said Bode. “There might be buildings that use a lot of water, so a lot of water goes down the drain. There are others that may have food processing like, for example, if you have a residence hall with a dining area, you're gonna have a lot more kind of food residue going down the pipes.”

That also means before any testing, Bode’s team has to collaborate with the city to see if the storm sewers and sewage systems converge.

With the help of student researchers, they collect the wastewater with a tool called a composite sampler.

“It's an instrument that's designed to take a small volume of wastewater at specific time intervals over say, 24 hours,” said Bode.

Once it’s in the lab, they start with around a liter of wastewater. They process this “matrix” so they can concentrate and measure COVID-19. Bode says, by their final tests to find the viral RNA, its volume is the size of a single drop of water.

Science is hard, Bode says, and that’s why it is by nature a communal process. But it’s also hard to collaborate during a pandemic.

“Now we're having to go into our research laboratories one at a time, or two at a time if the lab is large enough, and no more,” he said. “And so the isolation we feel at home, kind of is extending into the laboratory as well.”

That often makes the process slower, which can be frustrating when COVID-related science is often asked to go at warp speed. Bode describes it as a dynamic tension.

Luckily, with wastewater testing, they’re part of a consortium of colleges sharing techniques and best practices.

Bode reiterated that as effective as they hope wastewater to be, it’s just one part of the university’s testing strategy. It’s definitely not a silver bullet.

“These are going to be part of a larger program that helps us eventually get this under control,” he said.

In the meantime, he says, personal mitigation methods -- like wearing masks and social distancing -- are going to play a pivotal role in containing the spread of the virus.