WIMBLEDON, England -- Wimbledon officials played down swine flu fears Monday after four ball boys and girls were asked to remain home because of flu symptoms.

The All England Club urged all visitors and personnel to stay away from the tournament if they develop any symptoms. The club stressed, however, there was no reason to suspect swine flu had reached the Grand Slam event.

"There's no one that has swine flu," All England Club spokesman Henry O'Grady said. "There are a couple of people that have flu symptoms, and as a result they've been asked to stay at home. ... They haven't been tested for swine flu, and they're not going to be tested."

O'Grady said he did not have any information about the staffers' ages or whether they went to the same school.

Five-time champion Roger Federer said the players were told about the flu cases a couple days ago.

"For sure, not good news," Federer said after beating Robin Soderling in straight sets to reach the quarterfinals. "Especially for the players traveling around the world, meeting so many people. It's obviously not a good thing. But I'm sure the club, ATP, ITF, they're trying their very best to protect us as much as they can. Being careful, I think, is very important right now."

Venus Williams, who advanced after Ana Ivanovic retired with a thigh injury in the second set of their fourth-round match, didn't seem too concerned about the illness.

"I guess there's sicknesses all around. Hopefully the players won't get sick," Williams said. "Hopefully our immune systems are strong enough. That's what they're there for. We're going to all put ours in use, take vitamin C, keep playing and call it a day."

A hospital in Birmingham said Monday a 9-year-old girl infected with swine flu had died, the third fatality related to the illness in Britain. A 73-year-old man and a 38-year-woman who was pregnant died in Scotland this month after catching the disease.

Britain's health ministry says there have been 1,604 new cases of swine flu reported since Friday, bringing the total in the United Kingdom to 5,937. Britain is the hardest-hit nation in Europe with swine flu.