Wastewater helps find positive COVID-19 cases at UA dorm

TUCSON, Ariz. (KOLD News 13) - Wastewater samples from the Likins dorm on the University of Arizona campus came back positive for COVID-19, according to university president, Dr. Robert Robbins.

Dr. Robbins said they tested the water again, and all five samples came back positive.

He said they performed roughly 311 COVID-19 tests on students and staff in the Likins dorm, and found two positive cases.

Dr. Robbins said those individuals are now in isolation, and they are conducting contact tracing. He said wastewater collected from the other dorms showed no traces of COVID-19.

The Director of the University of Arizona West Center, Dr. Ian Pepper and his team are sampling sewage from dorms to determine if someone is positive for COVID-19, even if they are not showing symptoms.

Dr. Pepper said tracing sewage water can be one of the first methods to detect a resurgence of the virus.

Dr. Pepper said the method is accurate, and it can pick up a single positive case in a group of 10,000.

Studies have shown viruses can be detected in wastewater two-to-three weeks before many patients are diagnosed.

People shed viruses this way, and it is an easy, quick way to get a general idea of the kind of presence a virus has in an area.

“Sewage surveillance is a leading indicator as opposed to deaths, that’s a lagging indicator. That’s the last thing you see,” said Dr. Pepper.

The researchers are not yet able to tell exactly how many people have a virus, like COVID-19, from the sewage water samples, but can see if things like social distancing are working by tracing the virus levels found in samples. The group started collecting samples in Tucson in mid-March.

Dr. Robbins said since campus reentry, they have tested more than 10,000 people and less than 50 have come back positive for the virus.