JEFFERSON CITY, Mo. – Researchers in Missouri have been testing wastewater for spikes of COVID-19 for nearly four years, but could the same be done to test for the flu and RSV?

Missouri is currently reporting less than 200 flu cases. That’s down significantly from last year at this time, when the state was reporting 2,000 cases. Those low numbers aren’t slowing down the Department of Health and Senior Services (DHSS) from testing sewer water. 

For the last several weeks, it’s been fairly low,” said Jeff Wenzel, chief for the Bureau of Epidemiology for DHSS. “We only have about seven locations that have seen an increase in viral load. Our testing is pretty unique in the way we do it. We’re able to find those new lineages without really knowing it’s there.”

It’s a dirty but important job: testing your wastewater for COVID-19. For nearly four years, the state’s health department has partnered with the University of Missouri to test hundreds of samples. 

“Individuals can start shedding that virus before they know their symptoms,” Wenzel said. “So, we see an increase in trends about five to seven days before we see an increase in trends in other models such as hospitalizations.”

The University of Missouri tests roughly 100 samples each week from 90 different locations across the state. Wenzel said DHSS is now branching out to test for other viruses. 

“We’re not just focusing on COVID anymore,” Wenzel said. “We’re looking for things like flu. We’re just starting to test for RSV.”

Last summer, Gov. Mike Parson met with DHSS to thank state workers for all they did during the pandemic. During his visit, he told them he received a phone call from the vice president shortly after Missouri started testing wastewater in 2020. Parson said Vice President Mike Pence asked him how Missouri developed this idea which led to many other states implementing the model program. 

“We grew very fast, faster than most,” Wenzel said “We were able to quickly get up to covering 50 to 70% of the state,” Wenzel said. 

Before the samples are shipping to Mizzou, a wastewater operator uses an auto sampler which takes a little bit of a sample every 15 minutes from the sewage and accumulates it in a jug. Then, a sample of that 350-milliliter bottle is sent in for testing. 

While COVID and flu cases remain low, Wenzel said this type of testing could be used for years to come. 

“Sniffles and cough could be a lot of different things but if you had sewer shed testing that was able to look at 20, 30 or 100 or all the different virus to know what is in the area, that might help physicians,” Wenzel said. 

He said the state is still in the beginning stages of the flu and RSV testing, so the department is not releasing numbers publicly yet. 

DHSS recently launched a new flu dashboard on its website, keeping track of the number of cases and hospitalizations.

For a closer look at the Missouri Sewershed Surveillance Project, click here.