Observed Versus Expected COVID-19 Infections Among National Football League Players During the 2020 Season.

Background: The National Football League (NFL) and National Football League Players Association implemented a set of strict protocols for the 2020 season with the intent to mitigate COVID-19 risk among players and staff. In that timeframe, the league's 32 teams completed 256 regular season games and several thousand meetings and practices. In parallel, community cases of COVID-19 were highly prevalent.