MARGARET WARNER: Now, we're joined from Geneva by Dr. David Heymann, Director for Communicable Diseases at the World Health Organization. Dr. Heymann, welcome, and thanks for being with us.
DR. DAVID HEYMANN: Good evening. Thank you.
MARGARET WARNER: This has been called a new disease. What does that mean and what are the implications of that for the world health system?
DR. DAVID HEYMANN: Two weeks ago when we first recognized the disease, we didn't know the cause, so it was a new disease; we didn't know the cause and we didn't know how it spread from person to person. And we did know very few things about it. We knew, for example, that it did affect health workers as the first target. The first people affected seemed to be those who were taking care of patients with the disease. And we also knew that this disease could spread because it had already spread to Canada.
MARGARET WARNER: So what more do you know now about the cause?
DR. DAVID HEYMANN: Well, now we know that the disease is caused by a virus. We're almost certain that it's a corona virus, which is a virus similar to the virus that causes the common cold. We believe this virus may be coming from some source in nature, possibly from an animal. It entered human beings and then began to spread in humans and now is spreading from person to person.
MARGARET WARNER: And in spreading from person to person, how close does the contact have to be between people? In other words, how infectious, if you can use that word about a virus, is this?
DR. DAVID HEYMANN: Remember that we only have three weeks' of information about this disease, but we believe that it's spread only by very close person-to-person contact, or by body secretions or other parts – other infectious material from a human, which might be in the environment, for example on a door knob, and if this virus is still fresh, just having come from an infected person, someone touching that door knob could infect their fingers and then if they touch eyes or nose or mouth could infect themselves with the virus. So it's very close and intimate contact that must be had with the virus.
MARGARET WARNER: Now some of the doctors in Hong Kong looking at this case where in one sort of housing area more than 200 people have gotten it and more than 100 on a single block are beginning to say, well, maybe it's also carried through the air or through the water system. What's your thought on that?
DR. DAVID HEYMANN: Well, this is a clustering disease which is occurring in the same location. Now there's no reason that it still is not by close contact with a human or with body secretions, and what may have happened is the virus has gotten into the environment and then through a system that might be common in all these apartments, such as their sewage system or water system, it might be communicating with those apartments and at the same time spreading the disease to people who live in those apartments.
MARGARET WARNER: Now what percentage of the people who get this eventually die, and what treatment is there to keep them from dying?
DR. DAVID HEYMANN: Well, the good news is that 90 percent of people, we believe, get better. They gradually by day seven seem to be better -- 4 percent of people who get infected, however, do die, and about 6 percent become very seriously ill and it takes quite a while for them to recover. So we're dealing with a disease which has a death rate of about 4 percent, which is reasonably high for an infectious disease, especially if it's occurring in health workers, who are the mainstay of our hospital system.
MARGARET WARNER: But I gather there's really no known treatment for it yet in terms of an antibiotic or something like that.
DR. DAVID HEYMANN: That's correct. We have 80 clinicians around the world, 80 doctors who are dealing with this disease who are linked to a WHO on a regular basis every other day, every three days, exchanging information about what they've used to treat the disease. From discussions with those doctors we understand that there are really no anti-viral drugs that are effective in curing the infection but that by maintaining a patient until his or her body can develop the antibodies to cure this disease, we can make sure that they do get better, so patients must be sustained in life until their body itself can fight off the infection. This sometimes requires a respirator.
MARGARET WARNER: So how worried are you that we're on the beginning of what could really spread into some sort of worldwide epidemic, and what are you doing to try to contain that from happening?
DR. DAVID HEYMANN: The reason two weeks ago that we made a global alert about this disease is because we wanted to be sure that health workers throughout the world were aware of this disease so that they could treat it with respect if they suspected the disease. At that time we gave a definition of what the disease looked like and where it originated, and we told people that health workers were at most risk. Since we've made that alert, more than 13 countries worldwide now have the disease. But in those countries which identified the virus or the disease, after we made the global alert, there has been only minimal spread; whereas in countries before the alert there's been considerable spread. Canada, for example, was a country that first had the disease before we made the global alert, and they've had a serious epidemic or outbreak among hospital workers.
MARGARET WARNER: So what can individuals do? For instance there have been some cases reported in the United States, though no deaths. What can individuals do in a preventive way?
DR. DAVID HEYMANN: What's important is that everyone understands what the disease looks like, its signs, its symptoms, and also that they realize that the disease can only be contracted by close contact with someone who has the disease. So if they develop a disease with a high fever, a dry cough, and have had exposure to somebody who had the same or had this disease called SARS, they should then notify their health worker preferably by telephone or by sending someone to that health worker and isolate themselves from other people so that they don't pass the disease on.
MARGARET WARNER: What does the response to this say about the ability of the world health system to respond to some other kind of new disease, some kind of bioterror attack of unknown origin?
DR. DAVID HEYMANN: What we've seem from this outbreak is a solidarity within the world which has been unknown in public health. There have been laboratories working together, 11 laboratories working together, sharing their data, to decide what's causing the disease. There have been epidemiologists, people who study the transmission patterns of the disease, working together by telephone, through teleconference in Geneva, learning what others are learning and learning how best to prevent the disease, and at the same time we have doctors working around the world linked into WHO and other doctors exchanging information on how to keep people alive with the disease. So we're seeing an unprecedented global response which is necessary for naturally occurring infectious diseases and would also be necessary should there be deliberate use of an infectious disease to cause harm.
MARGARET WARNER: Dr. David Heymann, thanks so much.
DR. DAVID HEYMANN: Thank you.