Photo Credits: Cathy Tang / Aggie
Screening for COVID-19 variants and testing Davis wastewater are also under way
On March 1, Healthy Davis Together opened a new COVID-19 community testing site at Marguerite Montgomery Elementary School in South Davis.
UC Davis Health Director of Business Development Tod Stoltz explained that this is one of the smaller COVID-19 testing sites.
“It’s a small site, so we’re not going to get a ton of people there,” Stoltz said. “Last week, we had it open four days, and just a little over 400 people were tested there. We didn’t have any test sites in South Davis, and that was a good site to open to make it convenient for people in South Davis.”
Healthy Davis Together is considering opening another testing center as well, based on the success of this latest one, Stoltz said.
“The natural choice would be [in] West Davis, where we also don’t have a lot of test sites,” Stoltz said. “So that’s where we’re thinking about, but we’re going to see how Montgomery goes for another week or so.”
Some may wonder about the accuracy of the polymerase chain reaction (PCR) tests being administered. Stoltz clarified via email that the sensitivity and specificity rates of the tests are both “north of 95%.” Sensitivity is the true positive rate, whereas specificity is the true negative rate.
Stoltz elaborated that Healthy Davis Together is screening all positive testing samples for three different variants of COVID-19.
“There are three variants of concern, and these are published by the CDC. We are screening all positive samples for those variants of concern,” Stoltz said. “We are also working on screening wastewater for variants as well.”
Healthy Davis Together screens Davis wastewater for COVID-19, and it recently posted its wastewater screening data.
Hannah Safford, a fourth-year environmental engineering Ph.D. student and core member of the wastewater team, explained via email that wastewater screening data can show COVID-19 infection ratios in different areas.
“The same level of detected SARS-CoV-2 is more alarming if it comes from a region with relatively few people (since that means that the ratio of virus to people is high) than if it comes from a region with a lot of people,” Safford said.
The goal of the wastewater testing is to assess which parts of Davis may be experiencing increased amounts of COVID-19 infection, according to Safford.
“We’ve recently scaled up our [wastewater] sampling to include additional sites, including some that ‘zoom in on’ smaller, higher-risk areas of the City,” Safford said. “If we see trends in these areas that are alarming (i.e., if COVID levels increase or stay constant while overall levels in the City are going down), it could motivate [Healthy Davis Together] to take interventions such as deploying mobile testing sites to those areas, focusing messaging on those areas, etc.”
Written by: Rachel Shey — firstname.lastname@example.org