Blackburn boss Sam Allardyce has confirmed three of his players are ill with swine flu ahead of Tuesday's Carling Cup tie against Peterborough.There are now believed to be five cases at the club in total.
"We have had one more case this morning, one more player and there are a couple of staff," said Allardyce, who refused to name the players concerned.
Reports had suggested Rovers would seek to postpone Tuesday's tie but the game at Ewood Park is set to go ahead.
Allardyce had earlier told the club's official website: "David Dunn and Chris Samba have a virus."
Both Dunn and Samba were missing from Blackburn's squad for the 5-0 defeat at Chelsea on Saturday.
Asked whether they were two of the players suffering from swine flu, Allardyce stated: "It's definitely swine flu - you've speculated on the names and I'll leave it at that."
Allardyce said Blackburn had only decided to play the fixture at Stamford Bridge because Rovers were bound to do so by Premier League rules and admitted there was a chance the virus could have been passed on.
"The Premier League has tried to sit on the fence by saying that we didn't request to have the game called off," added Allardyce.
"We knew we couldn't get the game called off because we were told way back in February or March when we took some guidelines that unless there was some government legislation, everybody had to do whatever they had to do.
"If there was a swine flu outbreak, you couldn't call a game off, no matter what.
"We fulfilled our responsibility by confirming two cases of swine flu and suggesting that it looks like one or two other players and members of staff had similar symptoms - and we made the same phone call to Chelsea."
Asked about the danger of it spreading on a match day, Allardyce commented: "It's a highly contagious strain as everybody knows but I can't comment any further than that."
A Premier League spokesperson told BBC Sport: "Blackburn made contact with the Premier League on Friday to report the outbreak of swine flu but did not request for the fixture against Chelsea to be postponed.
"The Premier League does not anticipate at this stage a situation where any game will be postponed as a result of swine flu.
"Any postponement will have to be granted by the board of the Premier League and clubs would have to prove they couldn't fulfil the fixture with the first-team squad available to them.
"For a fixture to go ahead they only have to have seven fit players and can also sign players from their reserve and youth teams in the lead up to the match.
"The Premier League are telling clubs to seek and follow government advice when it comes to preventing or dealing with swine flu and take necessary precautions."
BBC Radio Lancashire understands that Dunn trained on Monday and is available for selection for Tuesday's tie against Peterborough.
Blackburn would have needed to apply for special dispensation from the Football League to postpone the Carling Cup match but are happy for the game to take place.
Allardyce said: "If we don't have too many more players go down with it, we've got a very good side for tomorrow," he said.
"We were going to make some changes to the side anyway - but
certainly we will be forced into those changes now.
"There will be a few players that were 100% on Saturday playing again, and a few players who haven't played as much in the first team who are also 100% who will be selected for the side against Peterborough."
Meanwhile, Peterborough manager Darren Ferguson is hopeful his Championship side can shock their Premier League opponents.
"It is certainly an unusual build-up to a game but it hasn't affected our preparations at all, we are preparing in the usual way," he said.
"I'm sure it may disrupt them but we were only made aware of it this morning.
"I believe Chris Samba and David Dunn didn't travel on Saturday and maybe two or three others have symptoms but I'm sure the game will go ahead.
"I don't know what team they will play anyway. They lost 5-0 at the weekend and play Manchester United on Saturday so there is every chance that they will make changes regardless.
"We'll have to wait and see but we go there with the belief that we can get a result."