Doncaster Rovers are the latest club to suffer a swine flu scare after two youth-team players contracted the virus.
Premier League rivals Blackburn Rovers and Bolton Wanderers have both reported cases of the virus in the past week and now Doncaster have been hit by the bug.
The Championship club have confirmed two members of the youth team are suffering from the virus, while other cases are being investigated.
As a result, the club's Cantley Park training ground is only open to members of Sean O'Driscoll's first-team squad in a bid to prevent the virus spreading.
Rovers are preparing to take on Blackpool at the Keepmoat Stadium on Saturday as O'Driscoll's side go in search of back-to-back home wins.
Meanwhile, Rovers physio John Dickens has revealed captain Brian Stock's rehabilitation from an ankle operation has been put on hold after he picked up a virus.
Dickens said: "He's going to be off for a few days so as not to spread it to any of the other players."