LONDON, ENGLAND - OCTOBER 13: A detailed view of the NFL logo on the field during the NFL game between Carolina Panthers and Tampa Bay Buccaneers at Tottenham Hotspur Stadium on October 13, 2019 in London, England. (Photo by Naomi Baker/Getty Images)
How the NFL managed the coronavirus pandemic
04:13 - Source: CNN
CNN  — 

It’s Super Bowl weekend – a moment that many people, at the start of the season, did not think we’d ever see.

After all, when the season kicked off with the opening of training camp in late July, we were in the middle of Covid-19 spikes around the country, and football is the very definition of a contact sport – contact being one of the activities we’ve been exhorted to avoid in order to avoid getting sick and slow the spread of the virus.

Yet here we are: Super Bowl LV with the Kansas City Chiefs facing off against the Tampa Bay Buccaneers at Raymond James Stadium in Florida; 25,000 fans in attendance, including 7,500 specially-invited (and previously vaccinated) health care workers, sitting alongside 30,000 cut outs. The fans will all get PPE kits that include KN95 masks when they get to the stadium. And yes, even the vaccinated fans will be required to wear one.

The story of how we got here – how the NFL was able to start and finish its season mostly without igniting major Covid-19 outbreaks – is a fascinating one for sports fans and scientists alike. It was published last week as a report in the Morbidity and Mortality Weekly Report, one of journals published by the US Centers for Disease Control and Prevention.

It turns out many of the lessons learned during the season-long experiment are helpful beyond the gridiron, and are applicable to society at large.

How we got here

Back in the summer, many wondered how football – with its tackles, huddles, heavy breathing, sweat and spit spewing, packed locker and weight rooms, loud cheering from fans – could make it through an entire season without igniting Covid-19 outbreaks left, right and center.

Experts, in both sports and public health, had their doubts.

“Think of the size of football rosters, and think of the nature of the sport with contact on every play. … It may be unlikely that the NFL can get in a full season,” veteran sportscaster Bob Costas told me and Anderson Cooper during a CNN coronavirus town hall in late July.

Infectious disease expert Dr. Anthony Fauci incurred the wrath of former President Donald Trump on Twitter a month earlier when he told CNN, “Unless players are essentially in a bubble – insulated from the community and they are tested nearly every day – it would be very hard to see how football is able to be played this fall. If there is a second wave, which is certainly a possibility and which would be complicated by the predictable flu season, football may not happen this year.”

But bubbling up wasn’t in the cards. Dr. Allen Sills, the NFL’s chief medical officer since 2017, told me it was “neither practical nor appropriate” to construct a bubble like the NBA had. While the entire basketball season could be played out at a single location, with football, it just wasn’t possible.

When the NFL decided to proceed with the season, Sills and other NFL officials faced the unprecedented challenge of how to make football as safe as possible for everyone, from the staff to the players and their families.

“I feel like it’s the right thing to do to try to learn to live with this virus. I really do,” Sills said back in July.

“This is a struggle that people are dealing with in all facets of life. Schools, businesses, places of worship. Everyone’s trying to figure out, can we reopen and do some of our activities and still mitigate risk? And I think it’s really important that we take the approach of trying to learn how to live with this pandemic as best we can,” he said at the time.

So, in collaboration with the NFL Players Association, the CDC and other health experts and advisers, the NFL developed a plan to move forward. It included mitigation and surveillance measures in facilities and during travel and games. Those measures included mask wearing; testing on a regular basis and genetic fingerprinting of the virus for positive cases; physical distancing; proximity tracking devices that captured information about who spent how much time with whom; contact tracing; hand washing; and facility disinfection and the rescheduling of games as well as education of staff, players and their families. In all, the plan covered about 11,400 players and staff from 32 teams across 24 states.

On September 10, when the Kansas City Chiefs kicked off against the Houston Texans in the first game of the season, there were just under 6.4 million confirmed Covid-19 cases in the US, with a seven-day average of more than 35,000 new cases a day. That seemed like a lot back then, but by point of comparison, the country now has topped 26 million confirmed cases, with a seven-day average of about 137,000 new cases a day.

But while cases in the whole country exploded, the NFL was relatively untouched. According to the MMWR report, there were 329 confirmed Covid-19 cases between August 9 and November 21. That’s just 2.9% of the 11,400 players and staff tested – statistics any state would be proud of.

And when unpublished results through January 30 were tabulated, the NFL said, there had been approximately 957,400 tests administered with an overall positivity rate of less than 0.1%.

Only three people – one player and two staff members – were hospitalized briefly and there were no deaths, Sills told me when I interviewed him again for this story earlier this week.

Lessons learned

One key component built into the NFL’s plan was flexibility – the ability to pivot to a new strategy if a Covid-19 outbreak emerged.

“One of the things we’ve all learned in the medical community about this pandemic is it breaks rules. It doesn’t follow what we think might happen. And so we’ve had to really try to pay very close attention to what our data is telling us and to be willing to bend and adapt and modify our protocols,” Sills said.

Was it smooth sailing? No. An outbreak early in the season forced the NFL to examine the data and slightly change direction.

“Early in September, we had an outbreak in Tennessee and we went in and really dug into that and tried to understand how the transmission occurred despite our protocols,” explained Sills.

While the CDC defines “close contact” as being within 6 feet of an infected person for a total of 15 minutes or more over 24 hours, Sills said the NFL’s data found transmission had occurred in less time and at greater distances. They were able to tell because all the players and staff were required to wear proximity devices that captured the consecutive and cumulative time of interactions among people within 6 feet of one another.

“That’s when we began to realize it wasn’t just 6 feet in 15 minutes,” said Sills, who noted not all close contacts are created equal. “And so we began to stratify contacts into what we call high-risk close contacts and just sort of regular contacts.”

That meant the exposure they needed to limit had to be expanded to what Sills termed “eating, greeting and meeting.”

“Meeting inside: even if you’re more than 6 feet apart, if you’re in a poorly ventilated room for a long period of time, if someone’s positive, there can be transmission inside those rooms. Eating together: most people don’t have a mask on when they’re eating. And then greeting: just the social interactions outside the facilities. When you interact in the community, if someone is positive and you go and get a haircut or you have a massage at your house,” he said.

In response to this new information, several league-wide changes were put into place. The first involved tighter restriction for seven days when a positive test result was received; the second was more frequent testing; and the third was expansion of contact tracing and transmission risk assessment that focused on identifying high-risk contacts.

But now, in addition to time and distance during an exposure, high-risk contacts also took into account face mask use (including the type and the fit) and the ventilation in the setting where that exposure took place.

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“We came up with this four-part matrix, which said, let’s think about, what is the ventilation status of the exposure? What’s the mask status of the individuals?” Sills said. “We also then would consider how much cumulative time of exposure and the distance. If you’re failing in two or more of those categories, that’s what we considered a high-risk close contact.”

The biggest lesson of all, according to Sills? “I think the biggest thing we learned, which is not shocking to those of us in the medical profession: Universal masking works. It’s the most effective strategy that we have.”

Beyond football

While the NFL certainly has more resources than most other organizations, the lessons that emerged from the great experiment can potentially be used in other situations.

“When you boil it all down, it wasn’t the fact that we tested every single day. It wasn’t the fact that everyone wore a fancy proximity tracking device everywhere they went. What prevented transmission was mask usage, avoiding in-person meetings, staying in the open-air environments, not eating together, prompt symptom reporting, isolation of anybody that’s exposed. None of those things that I just mentioned take a lot of resources,” Sills said.

In other words, they’re the same basic rules we have known since the beginning of this pandemic – with more evidence than ever that they actually work.

It’s a lesson you can apply this weekend, whichever team you are rooting for. Play it safe; don’t turn your Super Bowl gathering into a superspreader event – mask up, keep physical distance, make sure there’s plenty of air circulation, and please don’t double-dip into the guacamole.

CNN Health’s Andrea Kane and Nadia Kounang contributed to this report.