Difficult struggles remain in mainland China, but the epidemic there, although large, is no more complex than it is in other countries and the government is making great strides, said Mike Ryan, WHO's coordinator of the global effort to stop the severe acute respiratory syndrome virus.

Scientists from 16 SARS-struck locations concluded a one-and-a-half day conference Saturday at the WHO's Geneva headquarters, where they discussed the key factors that allow the virus to spread, the effectiveness of control measures and what remaining questions need to be answered.

"The message coming out of this meeting is certainly one of great hope. It's one of celebration that the measures are working, but also a call to action because we've got a lot more to do yet before we end this problem," Ryan said in a conference call with reporters.

"The experience across the range of countries involved has been that the control measures that we designed at the beginning of the epidemic have worked. In country after country, we have managed to break the cycle of transmission through the simple implementation of good case finding, contact tracing and isolation practices in hospitals," Ryan said.

"We have seen the number of secondary cases per case dropping systematically in all of the countries to a point now where we believe, in the majority of cases, we are now seeing the epidemics coming to an end," he said.

SARS has infected more than 7,800 people around the world and killed 625.

Taiwan on Saturday announced its biggest one-day jump in those infected, raising the total number of SARS cases on the island to 308. Singapore said fears of a SARS outbreak at a mental hospital were unfounded, leaving it on track to be declared free of the disease.

The main lesson of SARS, Ryan said, is to be prepared and organized.

"Managing an outbreak as serious as SARS requires very good collaboration between all services. The lesson for any future epidemics is really how we organize ourselves. We probably need to do that better in future," Ryan said. "It's about having in place good preparedness measures, good communication systems between the different sectors of government, early decision-making and systematic implementation of what's been decided."

Dr. Margaret Chan, director of Hong Kong's Department of Health, said epidemiologists at the meeting concluded that the pattern of the SARS outbreaks is similar in different places.

The belief that SARS is spread almost exclusively by droplets from coughing and sneezing emerged clearly from the discussions, Chan said.

It is possible that the virus could be contracted through feces if it becomes so fine that it can be inhaled, the scientists concluded, but there is scant evidence that it can be spread by feces-contaminated hands touching mouths.

Questions remaining include whether people have caught the virus but did not get sick enough to be noticed and whether people can spread the bug before they develop symptoms.

Ryan said some evidence indicates that there are mild cases but no sign that those sufferers have spread the virus.

The same is true for those who have been quarantined and later developed SARS.

"We are reiterating that there is no sign of infection coming from people before they start developing symptoms," said Angus Nicoll, from Britain's Health Protection Agency. "There are one or two circumstances that need further investigation, but nobody was reporting that as a phenomenon."

(China Daily May 18, 2003)