Another British pupil in China is said to have tested positive for swine flu.
Nine British and nine American children who were on an exchange trip to China are now being treated for the virus in hospital in Beijing.
More than 100 of their classmates and teachers are also under quarantine, which means they're being kept away from people to stop the flu spreading.
Others who weren't in close contact with the pupils who've fallen ill are continuing their trip to other areas.
Gavin sorts out the fact from the fiction about swine flu
Meanwhile, in the UK a special helpline is being set up by the government to offer people advice about swine flu.
There will also be new walk-in centres to help cope with the outbreak in the England.
It's thought Wales, Scotland and Northern Ireland will have their own flu fighting stations soon.
The first four pupils who were found to have swine flu in Beijing are year nine pupils, from different areas of London.
Among them is Matthew Barnett, who told reporters from his hospital room that he was feeling "OK".
Matthew said he was taken to hospital after a routine temperature test at the hotel found his to be higher than usual.
"They put me in this separate room and said 'you have to stay in here and not make contact with anyone else'," he said.
"I've been treated fine, they've been very nice and the food's very good."
More than 600 pupils from different schools are on the trip to China to learn more about the country's culture and language.
Organisers of the trip said the pupils in hospital were being well looked after and were even getting pizza delivered.
They added that most of the pupils were continuing their trip, and the 52 British pupils and teachers under quarantine in a four-star hotel were very comfortable.