Hysteria already, really? Were you all under the impression that they were doing all this testing without any expectation of anyone actually catching the virus?
The whole reason for the constant retesting is so that an infection can be safely caught and prevented from spreading with minimum disruption to the season. I don't know exactly what the PL's plan for this situation is but presumably if it is a player (and it could easily not be) then the squad can isolate for the day or two until the next round of testing. Then if it turns out any other players have been infected they will isolate until virus free, and the rest of the squad can immediately get back to work. It's a three day delay even if they don't get specially tested. It's possible they will be - that a positive test will trigger an immediate retest of the rest of the team in question, bringing the delay down to only one or two days. Either way it's entirely manageable. And we have actual proof of that in the form of the Bundesliga, running very smoothly indeed all things considered.