By Jaclyn Peiser
August 28, 2020 at 4:50 a.m. CDT

As 5,000 students prepared for move-in day at the University of Arizona this week, the school warned they would be tested periodically for the coronavirus. One test, though, doesn’t involve a nose swab. The university is regularly screening the sewage from each dorm, searching for traces of the virus.
On Thursday, officials said the technique worked — and possibly prevented a sizable outbreak on campus. When a wastewater sample from one dorm came back positive this week, the school quickly tested all 311 people who live and work there and found two asymptomatic students who tested positive. They were quickly quarantined.

“With this early detection, we jumped on it right away, tested those youngsters, and got them the appropriate isolation where they needed to be,” said Richard Carmona, a former U.S. surgeon general who is directing the school’s reentry task force, in a news conference.

Researchers around the world have been studying whether wastewater testing can effectively catch cases early to prevent covid-19 clusters. There are programs in Singapore, China, Spain, Canada and New Zealand, while in the United States, more than 170 wastewater facilities across 37 states are being tested. Earlier this month, officials in Britain announced testing at 44 water treatment facilities. The Netherlands has been collecting samples at 300 sewage treatment plants.