As schools struggle to reopen safely, the University of Arizona is innovating by testing wastewater to catch COVID outbreaks before they start
The University of Arizona stopped a COVID-19 outbreak on campus in its tracks by discovering two students who had the virus, but were asymptomatic. How did they do it? By testing wastewater.
Yup. Apparently our waste says a lot about our health, because testing wastewater samples from the Likins Hall dorm in Tucson revealed COVID-19, which prompted the institution to test all 311 students and staff at the dorm, according to university president Dr. Robert Robbins. The two students who tested positive were isolated as the school conducts contact tracing.
Dr. Ian Pepper, Director of the University of Arizona West Center, is leading a team in testing sewage samples from dorms to detect the virus — which can lead to finding positive cases in that dorm building. Pepper says tracing sewage water can lead to picking up a single positive case out of 10,000 people. Studies have shown that some viruses can be detected in wastewater a full two to three weeks before an official diagnosis of illness.
Pepper explains that the wastewater testing method is proactive rather than reactive, therefore, stopping a virus outbreak before it starts. “Sewage surveillance is a leading indicator as opposed to deaths, that’s a lagging indicator. That’s the last thing you see,” he says.
Robbins says that since campus reopened, the school has tested more than 10,000 people with only 50 showing up positive.
Pepper spoke on the “Arizona Science” podcast about his work sampling sewage saying, “poop can tell you the truth about yourself and your community.”
“By analyzing the sewage, we’re actually monitoring the whole community with one test,” he explains. Pepper notes that wastewater testing can give “the total virus load shed by infected individuals both with symptoms and asymptomatic ― no symptoms.”
Pepper says “you can detect the virus in sewage seven days prior to symptoms appearing.” That means plenty of time to take action to prevent further spread. “That gives you seven precious days in which you can put in mitigation or interventions to try to deal with the virus,” he explains. “I think about a week in the U.S. is probably equivalent to 20 or 30,000 cases.”
The school isn’t the first to deploy this type of testing to prevent outbreaks, and the CDC is currently “developing a portal for state, tribal, local, and territorial health departments to submit wastewater testing data into a national database for use in summarizing and interpreting data for public health action.”