The NFL Players Association says that 56 players have tested positive for COVID-19 since players began reporting to training camps last week.

That represents approximately 2 percent of the players currently on NFL rosters.

The league would obviously love to see zero players testing positive, something the NBA and NHL have both managed by putting all their players into bubbles. But the NFL is not going to use a bubble, and so a 0 percent rate of infection is all but impossible.

Still, if the league and its players can keep the infection rate relatively low, the season can go on as scheduled, without having to cancel games like Major League Baseball.

The problem is that keeping the rate of infection relatively low is going to be very difficult once players are practicing with each other daily and playing against each other weekly. Even one infected player being able to practice before he knows he’s infected could result in the kind of outbreak within a team that the Miami Marlins had just days into the baseball season, leading to a chain reaction of games being canceled.

So the NFL and the players will need to be vigilant for the next six months if the league is going to have a complete season, up to and including the Super Bowl.