Concerns over rapid test effectiveness for UW Football after NFL COVID-19 outbreak

SEATTLE — Coronavirus outbreaks are disrupting the NFL season. This, as the Huskies held their first official football practice Friday.

The PAC-12 conference credited rapid daily COVID-19 testing for being able to start the season this fall, but now the test’s effectiveness is being called into question – particularly at detecting the virus in people without symptoms.

Huskies players get tested every day using the Sofia SARS antigen test, made by QUIDEL.

“Our players have just adjusted to this lifestyle. They come in, put a swab in their nostril, put it in a tube and away we go,” said Huskies Head Coach Jimmy Lake.

The testing happens in batches.

“Obviously we don’t want 115 guys coming in at one time. So we flight the guys here in the morning and they come in in groups. As they enter the building, we swab them,” Lake said.

They get results in about 45 minutes and Lake says any time spent in the building is with masks on and socially distanced.

“So if we did end up getting somebody that tested positive, we wouldn’t have to quarantine anybody because there is low contact,” Lake said.

However, daily testing has not stopped an outbreak in the NFL, which reported Wednesday that 11 players and 15 personnel recently tested positive for COVID-19.

The biggest cluster of cases is among the Tennessee Titans.

Daily coronavirus testing also failed to prevent a COVID-19 outbreak involving President Trump and more than 30 White House insiders.

UW Medicine’s Dr. Geoffrey Baird explains one of the downsides of rapid antigen tests.

“All of those tests have a serious decrement in their sensitivity, and yes – allow people who have the virus on board to get passed with a negative result,” Baird said.

It means the rapid tests are just not as good in catching the virus in people with no symptoms.

“Eventually the virus load goes up and up and up, and eventually gets up to a point where you can detect it. But in a specific case it doesn’t help you,” Baird said.

Public Health Officer Dr. Jeff Duchin said some antigen tests can also show false positives.

“In populations that are highly likely to have COVID-19 in an outbreak setting where people are symptomatic, a positive test is relatively reliable. But in screening with people who have no symptoms or not known to be exposed, a positive test has a high likelihood of being a false positive test. That should be confirmed with a PCR test,” Duchin said during a Zoom conference this week.

Coach Lake says those are concerns they’re very aware of, which is why all players also get those PCR (polymerase chain reaction) tests.

PCR tests are slower because they need to go to a lab for results, but it’s what public health calls the “gold standard” of COVID-19 testing.

“So we’re also doing the PCR testing three to four times a week. Will do double swabs on those days,” Lake said.

Doctors say what’s even more key in COVID-19 prevention are the measures like masking, distancing, and sanitizing.

“Testing itself is of secondary importance to all the behavioral modifications,” Baird said.

Some of those measures are impossible during football practice or games, but Lake emphasized they’re relying on layering together all the different safety measures to keep the team safe.

“Our players at this point have done a fantastic job of not dragging the virus into the building. We just have to continue that here for the next three months,” Lake said.

Two Huskies players, tight end Jacob Kizer and defensive back Isaiah Gilchrist, have decided to sit out the season because of coronavirus concerns.

Cox Media Group