UC Berkeley provided an update Thursday on recently detected COVID-19 in wastewater from University Village and Clark Kerr Campus, campus-owned housing units.
This finding follows a national surge in positive cases. The wastewater results are correlated with one case in each location, but UC Berkeley does not know at this time whether there are more cases, according to campus spokesperson Janet Gilmore.
Rose Kantor, program manager for wastewater monitoring research projects at COVID-Wastewater Epidemiology for the Bay Area, or COVID-WEB, said SARS-CoV-2, the virus that causes COVID-19, sometimes infects the gastrointestinal tract. This leads to the virus being shed in feces, which can occur even when a person is asymptomatic or tests negative through the traditional swab test.
“People typically get clinically tested maybe once per week, and in some places, if you’re asymptomatic, you won’t receive a test because you don’t know you need one,” Kantor said. “In university housing and in senior living facilities, people are getting tested regularly, but there could be a gap in testing.”
Given the lack of medical literature on COVID-19, Kantor noted that these wastewater results cannot currently identify how many individuals in a housing unit have COVID-19. This is due to the variable amount of SARS-CoV-2 that individuals shed in their feces, according to preliminary literature.
Kantor added that some infected individuals may never shed SARS-CoV-2 in their feces, while others may continue shedding the virus long after exhibiting symptoms or even being contagious.
However, according to Matthew Metzger, COVID-WEB lab manager, this method’s credibility is increasing as more testing is being conducted. Kantor added that while wastewater analysis cannot identify how many individuals have COVID-19, it is a useful tool to augment or supplement existing measures.
“I can tell you that, normally, when we do detect a positive signal, we immediately contact the medical staff leading the COVID response at UC Berkeley,” Metzger said. “In most cases, they corroborate the testing of a positive case that they’ve had or could be indicative of them being on the lookout for potentially unverified cases.”
As a result of the wastewater findings, UC Berkeley has sent a message to students in both units, encouraging them to get tested, and has set up free on-site testing at University Village. Gilmore recommended that students continue to follow COVID-19 safety protocols, such as social distancing, hand-washing and wearing masks when around others.
Kantor also noted the importance of wastewater testing in addressing the pandemic.
“It’s an important tool, but it doesn’t stand alone from clinical testing,” Kantor said. “We’re doing this to augment other health measures. It’s not a ticket to freedom from COVID-19 restrictions, so much as a reassurance to public health that we’re doing everything we can.”