RESEARCHING SARS
May 20, 2003

Susan Dentzer looks at how scientific research is contributing to the struggle against SARS. The NewsHour Health Unit is funded by a grant from The Henry J. Kaiser Family Foundation.

 

Online NewsHour Special Report: Combating SARS May 19, 2003: Berkeley reacts to the administration's decision to turn away students from some SARS-affected regions. May 7, 2003: Singapore's prime minister discusses their fight against SARS May 7, 2003: Singapore's prime minister discusses their fight against SARS May 7, 2003: Update: China's rural areas not ready to fight SARS. May 5, 2003: Update: SARS sparks protest in China, WHO to help Taiwan battle disease. May 1, 2003: Leading WHO scientist Dr. David Heymann discusses the global impact of SARS. April 30, 2003: Betty Ann Bowser reports on how SARS' presence has affected Toronto's citizens. April 29, 2003: Update: WHO lifts SARS-related travel advisory for Toronto. April 29, 2003: How the U.S. health care system treated the country's first known SARS patient. April 28, 2003: Gwen Ifill and two experts examine the mounting number of SARS cases in China, and the disease's political, economic and medical fallout. April 28, 2003: Update: SARS continues to spread in China, but the outbreak of the disease appears to have peaked in some other regions. April 25, 2003: Spencer Michels reports on how San Francisco is reacting to the spread of SARS in Asia. April 18, 2003: Experts discuss the impact of SARS on financial markets. April 7, 2003: How is the U.S. Health care system responding to SARS? March 31, 2003: Dr. David Heymann, of the World Health Organization, discusses the fight against SARS. Browse the NewsHour's coverage of the health   News for Students: Health officials respond to mysterious illness.     Center for Disease Control and Prevention World Health Organization	RESEARCHER: Can you kind of scan those in? SUSAN DENTZER: Here at the National Institutes of Health in Bethesda, Maryland, researchers have been hard at work for weeks on potential vaccines for SARS. RESEARCHER: Did this just not match? SUSAN DENTZER: The work began in mid-March, just as global health authorities were issuing their first alerts about the SARS outbreak. The research is possible because of an unprecedented global effort to gather information about the SARS virus quickly. RESEARCHER: But then your next one up is... SUSAN DENTZER: Dr. Gary Nabel directs the vaccine research center. DR. GARY NABEL: We went from having a virus that caused disease in early March to the point where there actually was a growing virus in cell culture a month later, and then literally within a couple of weeks afterwards, the DNA sequence was becoming available. SUSAN DENTZER: Dr. Anthony Fauci heads the Allergy and Infectious Disease Institute. He says those initial steps have paved the way for a multiyear effort to develop the tools for battling SARS. DR. ANTHONY FAUCI: Now, when you have all that information, then that gives you a real jump start on things like making diagnostic tests, screening drugs, straining antiviral drugs, and taking the first crude steps toward making a vaccine.
	Researchers find the cause of SARS
	SUSAN DENTZER: The United States isn't the only place where such work is going on. Government and private labs around the world are also engaged. Still, many early discoveries have in fact been made here, especially at the Centers for Disease Control and Prevention in Atlanta. Dr. Pierre Rollin heads a CDC Section that helped to identify the SARS virus in late March. He and his colleagues did that by injecting samples taken from sick patients into a special cell culture to see what would result. DR. PIERRE ROLLIN: You can see the normal cell all around, and in the middle, this gap where the cell disappeared. And so that clearly is something going on, killing the cell. SUSAN DENTZER: Other CDC scientists then examined the virus under an electron microscope, and saw the telltale crown of so-called coronavirus. These are a family of viruses that cause disease in a range of animals, and about 30 percent of all common colds in humans. DR. LARRY ANDERSON: Ultimately, when we get the labs, we're going to know how many are actually SARS corona-positive and how many aren't. SUSAN DENTZER: Dr. Larry Anderson heads the CDC branch in charge of respiratory viruses. With the virus's identity in hand, his group immediately set to work decoding the microbe's genome. That was completed by early April. It showed that SARS was a whole new type of coronavirus, different from the two types already known to affect humans and a third type that sickens animals. DR. LARRY ANDERSON: SARS genetically looks like it would be sufficiently distinct to be a fourth cousin in this family of coronavirus.
	Stopping the virus that causes SARS
	SUSAN DENTZER: Having the virus's genetic sequence made it possible for CDC researchers to take other important steps. First came the development of several diagnostic tests to detect the virus in the body or to find antibodies suggesting its presence. Dr. James Hughes heads the National Center for Infectious Diseases at the CDC. DR. JAMES HUGHES: It's very important to have a diagnostic test for this previously unrecognized infection for a number of reasons. First and foremost right now, what we need is a test that we can use for public health purposes and for disease surveillance purposes so that we can identify suspect cases, classify them as "suspect," "probable," or "confirmed." SUSAN DENTZER: A second step was launching a cooperative multi-agency research effort to look for drugs that could be used to treat SARS patients. DR. JAMES HUGHES: There is an effort now in collaboration between CDC, Food and Drug Administration, the National Institutes of Health, and the Department of Defense to evaluate candidate antiviral drugs to try to see if there is a currently available drug or drugs that have activity against this virus. DR. ANTHONY FAUCI: We're in the process of screening a wide array of compounds that already exist on the shelf, some of which are approved drugs, some of which are drugs that have just been developed but went nowhere down blind alleys. You go and you determine if it has activity in the test tube against the SARS corona virus. If it does and it's a drug that's already developed, well, then you've hit the jackpot. You're lucky. SUSAN DENTZER: Fauci says the jackpot hasn't been hit yet. But the screening effort has shown preliminary evidence that one existing antiviral drug, known as interferon beta, blocks the SARS virus in cell cultures in a lab dish. And in the journal Science, researchers in Germany reported that still another experimental antiviral drug might be able to stop the virus from replicating in the body. Perhaps the most critical research now under way aims to develop a SARS vaccine. Without an effective vaccine, there's almost no deadly infectious disease that has ever been eradicated or rendered less of a threat to humanity. DR. ANTHONY FAUCI: I think ultimately we'll get it. And the reason I say that is that greater than 90 percent of people who get infected with the SARS virus, their own body's immune system is able to completely clear the virus from the body. It gives me hope that we can develop a vaccine, that we're going to be able to boost the body's immune system enough so that when it gets challenged with SARS, it can protect itself against that. SUSAN DENTZER: At NIH, researchers are testing two different vaccine approaches. They say it may take them six months or more to determine whether the strategies work. Animal and human testing would then follow. That means that in the best of all worlds, a vaccine may not be available and licensed for use in humans for two to three years. DR. GARY NABEL: History would suggest that it is possible to generate immunity to this virus, but there are some coronaviruses that are more challenging than others, and I think as we study this virus in the laboratory, we very quickly begin to understand how much it mutates, how much it's like the viruses that we could contain in the past. So we're in a situation where we're receiving a lot of new information in real time, and we have to be prepared to adjust in real time. SUSAN DENTZER: Researchers hope to develop those disease-fighting tools in time to prevent thousands more deaths from SARS.