The SARS Outbreak: 100 Days Later
Worst of the SARS Outbreak Is over, But What's Next?
3 Critical Steps in Containing SARS Remain
But there is still a lot of work ahead for researchers before they can say the threat of SARS is over.
As officials have learned over and over again, it only takes one missed case to set off a cascade of new SARS cases or to export the disease to a new region. According to the WHO, a single, highly infectious person has been known to set off a chain of transmission that has led to nearly 100 additional SARS infections.
Before an infectious disease can be considered eradicated, officials at the SARS conference said, three prerequisites must be met:
- An effective way to stop transmission of the infection, ideally a vaccine, must be developed.
- An easy-to-use diagnostic test must be created to screen for infection.
- Infection of humans must be shown as the only way the virus can survive. If the virus can live in animals as well, eradication may be much more difficult.
Although the virus that causes SARS has been identified and sequenced genetically, health officials say the development of an effective vaccine against the SARS virus will take at least a year.
Several diagnostic tests for SARS are currently being investigated, but none are able to produce fast, accurate results yet.
CDC Director Julie Gerberding, MD, says they have the technological understanding to create screening tests for the SARS virus, but the biology of the virus has made knowing when to test for the virus problematic. For example, some people with SARS do not show evidence of the SARS virus until they develop pneumonia, while the virus can be seen in others before they show symptoms, which makes knowing when to take a sample difficult.
"Our expectations are so high these days, but the fact that we have several tests already at this very early stage, just months after detecting the pathogen, and that we can use them to confirm that people have this infection is a very optimistic perspective," says Gerberding. "Ultimately I think we will be successful in developing a bedside diagnostic test for this coronavirus, and that will be a tremendous help to us here and also globally."