But the Chinese government is worried that the illness is spreading after there was a big rise in the number of people with the disease in Beijing.
It's now told more than a million and a half kids to stay at home for two weeks from Thursday.
Governments take action
Many people in Beijing are wearing masks and the trains and buses are being sprayed with disinfectant to try and stop the virus spreading.
Governments in other parts of the world are also taking action.
In one Australian state, anyone thought to have the illness will be put into quarantine.
There have only been six cases of people getting Sars in Britain - and they've all made a full recovery from the illness after being treated in isolation in hospital.