Data shows asymptomatic individuals not spreading COVID-19, NFL chief medical officer says

The NFL's new COVID-19 protocols are based on data that shows the disease is not spreading from asymptomatic individuals, according to chief medical officer Allen Sills, a significant departure from the stance of public health authorities for much of the pandemic.

The NFL and NFL Players Association agreed last week to halt weekly testing on vaccinated players and begin random testing of a sample across teams and positions. Vaccinated players who report symptoms are required to be tested, and unvaccinated players continue to be tested daily.

The new protocols raised questions about the possibility that infections among asymptomatic, vaccinated players and coaches would go undetected, leading to additional transmission in team facilities. But speaking Thursday on the NFL Network, Sills said he has observed no evidence of it this season through the league's contact tracing system.

"We've really not seen this phenomenon that people have discussed, which is asymptomatic people in the facility spreading the virus to others," Sills said. "As we've gone back and looked throughout the entire season, what we've seen consistently is that when people have symptoms, that's when they seem to be contagious to others. And that's why we're asking people to come forward and acknowledge symptoms because that's the point at which they're vulnerable and the point at which they expose themselves to others.

"Our data has been consistent of that throughout the season, and I think it's particularly true of this new variant, with omicron, of what we're seeing. It's all about symptom recognition and prompt testing."

More than 94% of players and nearly 100% of coaches are vaccinated. A total of 46 players tested positive Thursday, according to ESPN's Field Yates, bringing the total to 154 this week and more than 300 in the past two weeks.

Players must isolate for 10 days when they test positive, but the new protocols give vaccinated players several options to test out sooner based on a combination of negative tests and control threshold (CT) readings, beginning as quickly as the day after their original positive test.