Football fans expecting a smooth return of the professional and college leagues this fall should temper their hopes, according to Anthony Fauci, the immunologist who directs the National Institute of Allergy and Infectious Disease.
"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," Fauci told CNN on Thursday.
The National Football League faced scrutiny earlier this week after several players on the Dallas Cowboys and Houston Texans on Monday tested positive for coronavirus.
The results heightened concern about whether a return to contact sports is a good idea in the midst of a pandemic.
"We expect we are going to have positive tests. That is part of the increased testing that we will be going through and that is something that we just want to make sure that our protocols are working and to date," NFL Commissioner Roger Goodell told ESPN.
"We are seeing very positive reactions in the sense that we are making sure we respond quickly, protect the personnel that may be impacted by that and others that may be in contact with them."
The NFL provided protocols for the gradual reopening of team facilities. The league hopes to have its infrastructure in place by the time training camp in rolls around in July.
But "[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," Fauci said.
The physician's comments come as the National Basketball Association attempts to iron out an isolation plan that will enable the league to resume its season on July 31. The NBA suspended the season on March 11.
The NBA's plan to return features that bubble, with 22 teams being invited into a closed environment at a Disney campus in Orlando to finish the season.
NBA teams are slated to begin arriving in Orlando on July 7.