The World Health Organisation (WHO) said it's now telling people not to travel there because Sars is spreading so quickly.
This comes as Cambodia reported its first possible case of Sars, after a 16-year-old boy who'd been travelling in China came down with symptoms.
Back to school
But in China, where Sars is thought to have started, things are getting better.
Thousands of children have gone back to school after many of them were sent home for a month to control the spread of the disease.