Severe Acute Respiratory Syndrome and the adoption of the world's first tobacco-control treaty are expected to dominate the agenda of the annual World Health Assembly, May 19-28.

The World Health Organization, which has been leading the global fight against the SARS epidemic, is following its own advice. The Director of WHO's Communicable Diseases Program, David Heymann, says delegates who do not pass a SARS screening test have been told to stay away from the assembly meeting.

"If there are participants on their delegation who have had contact with a SARS case, or contact with hospitals in which there is SARS in the previous 10 days, those persons should not travel to Geneva for the World Health Assembly," he said.

Before they are admitted to meetings, delegates will have to confirm that they have no SARS symptoms, such as fever, a cough or difficulty breathing.

A major item on this year's agenda is the formal adoption by the World Health Assembly of what is called the Framework Convention on Tobacco Control. This treaty has been under negotiation for four years. It calls for a worldwide end to tobacco advertising and sponsorship within five years. It also cracks down on smuggling, and prohibits marketing tobacco products to young people.

The World Health Organization estimates five million people die every year from tobacco related illnesses. It predicts this figure will double within the next two decades, unless some action is taken.

"I think we could argue that this piece of paper, when it is put into practice, could very well end up saving more lives than almost any other piece of paper, which we have worked on for a long period of time," said Derek Yach, the head of WHO's non-communicable disease program.

WHO Director-General Gro Harlem Brundtland is credited with having taken on the big tobacco companies and pushing through the anti-tobacco treaty during her five-year term in office. She also has pushed for stronger action to control infectious diseases, such as malaria and tuberculosis.

During this assembly meeting, she will be handing over her job to Jong Wook Lee, from South Korea, who heads the WHO tuberculosis program.