GWEN IFILL: We get the latest now on SARS in Canada and elsewhere. It comes from the World Health Organization's point man on the disease, Dr. David Heymann.
Dr. Heymann, thank you for joining us again. Since last time we talked, the worldwide death toll is now at 744 for SARS. Tell us what's been going on.
DR. DAVID HEYMANN: Though the death toll has increased, we're seeing that SARS is actually coming under control in many, many of the outbreak sites. In Singapore, for example, we believe that by this weekend 20 days will have passed without a new case of SARS, which would mean that transmission has been interrupted in Singapore. So provided things go as they have been going, Singapore will have interrupted transmission this weekend. Hong Kong is down to less than five new cases each day, which is quite impressive from the number of cases that were occurring just two or three weeks ago. And Hong Kong, we believe, will soon also have controlled the outbreak.
That leaves the big question in China is how can China control this outbreak? Will they be able to do it, and will they continue with the high level commitment that they have at present? We believe they will.
GWEN IFILL: In Toronto, we are hearing that it's been returned to the watch list. What's happened there?
DR. DAVID HEYMANN: That's right. In Toronto, there have been a cluster of cases, eight cases that have been reported to WHO, and 26 persons who are suspect cases. These are people who are in a chain of transmission which we believe began in the hospital after a surgical procedure on the index, or the first case.
This case perhaps picked up his infection from some equipment or something in the environment in the hospital where the virus had continued to thrive and remain alive since the last known case, and as a result there are others infected now and we do have Canada back on the watch list.
GWEN IFILL: And there is now a quarantine in effect in Toronto involving at least one entire school, is that correct?
DR. DAVID HEYMANN: That's correct. There's been a suspect case in one of the schools. And as a precaution, they've put the students under a quarantine where they're remaining at home and making sure that they don't develop fevers.
GWEN IFILL: Now help us understand. In the areas of the world where the SARS epidemic is still growing but at a slower rate, what are they doing right, and in areas of the world like Ontario, Canada, where it had been thought they were in the clear and they are not, what are they doing wrong?
DR. DAVID HEYMANN: We had a meeting of epidemiologists, those people who study and try to contain the outbreaks from around the world here in Geneva about ten days ago. And at that meeting, there were discussions of why some countries have succeeded in containing the outbreak earlier, made great progress, while others hadn't.
And it seems this might be related to the sophistication of the equipment in the hospitals themselves. In hospitals where there are apparati which will nebulize patients or which are used for pulmonary treatment-- these are sophisticated equipment-- it seems that in these hospitals it may be that the virus is easier spread than in hospitals where this equipment doesn't exist, such as in Vietnam. So we're seeing that this might be a disease which is transmitted easier in better hospitals.
GWEN IFILL: And it's also a very sturdy virus. Is there any way to know whether Canada let down its guard too soon?
DR. DAVID HEYMANN: Well, it's not useful to go back and look whether Canada let down its guard. What's important is that they have a system still in place that could find a case when it occurred and due to contact tracing necessary to identify other cases or suspect cases, and they've also now put a whole series of students under observation. So it's very important to know that outbreak control is still working in Canada, and the system is still there to detect disease.
GWEN IFILL: We are also hearing today for the first time of the first SARS case in Russia right along the China border. What can you tell us about that?
DR. DAVID HEYMANN: Well, this has been a worry in Russia for quite a while. There had been reports of possible cases from all along the Chinese border. So this is nothing new. What's important is that in this area there be a good surveillance or detection system set up, and our regional office of WHO will be working with the Russian government to make sure that that does occur.
GWEN IFILL: And in China, on Mainland China, we've heard some reports of suspicions at least of animal-to-human transmission. What can you tell us about that?
DR. DAVID HEYMANN: Well, the Hong Kong University and the Guangdong Centers for Disease Control, which is based in Guangdong Province, have done some studies in markets. Now these are rather haphazard studies, they're not systematic studies, but they've taken some animals and they've looked in these animals to see if they could isolate the virus. And from a member of the cat family, the civet, they have been able to isolate the virus. They've also done some looking for antibodies, that is evidence of disease, in animal handlers and in the general population.
GWEN IFILL: And they have shut down the wild game market in China, Beijing as well.
DR. DAVID HEYMANN: That's correct. Throughout China, the government has shut down the wild game markets, and this is because the virus has been found in animals, but again it's not clear whether these animals are the ones who are transporting it to humans from nature or whether there are other animals involved in this transition chain.
GWEN IFILL: And finally, Dr. Heymann, we've heard a lot and reported a lot about SARS in the last several weeks. How, now that you've been watching this for a while, does this compare to other contagious epidemics, even the flu, in terms of the kind of damage it's done and the kind of precautions that people should be still taking around the world?
DR. DAVID HEYMANN: Well, in the last 30 years, there have only been two infectious diseases that have emerged from nature into human populations and been able to sustain their transmission from person to person. One of those was AIDS about 25 years ago, 23 years ago, and then the current SARS virus. Other viruses have come out of nature into humans-- many viruses, in fact, about 30-- but they haven't been able then to transmit from person to person. For example, the bird flu in Hong Kong in 1997, came from chickens to humans, but fortunately it didn't transmit from human to human very easily, and the epidemic was rapidly stopped.
GWEN IFILL: And this makes it a more difficult epidemic to cope with?
DR. DAVID HEYMANN: This makes it a very difficult epidemic. The SARS epidemic is one which is perpetuating itself. It passes from person to person by close contact, and the only way to stop this disease is to find all persons with the disease, isolate them, and make sure that their contacts do not become sick. So it's a very important job that we're doing with the world together, in great solidarity, trying to drive this disease back into nature so it didn't doesn't remain with us in the future.
GWEN IFILL: Dr. David Heymann, thank you again for joining us.
DR. DAVID HEYMANN: Thank you.