On the heels of a presidential call to spend billions to fight the long-standing AIDS epidemic, scientists say there may be some lessons in the lightning speed at which researchers identified and mapped the SARS virus.
"Time is not on our side, so I ask Congress to move forward with the speed this crisis requires," President Bush said of HIV/AIDS Tuesday, calling for Congress to spend $15 billion to fund AIDS education programs and buy drugs to treat its victims.
Scientists have not found vaccines for either HIV/AIDS or SARS, but the pace of research on the virus behind severe acute respiratory syndrome was unprecedented.
Within just eight days, researchers identified the virus behind SARS, and in seven weeks they had zeroed in on its genetic structure. By contrast, it took scientists three years to identify the human immunodeficiency virus, the pathogen behind AIDS, and nearly two more years to map its genome.
How did they do it? Scientists say it was a combination of advanced technology, vital collaboration and a little luck.
"It was really quite a lucky break," said Michael Lai, a professor at the University of Southern California in Los Angeles, who specializes in coronaviruses — the class of viruses that includes the SARS pathogen, as well as about 200 of the known pathogens behind the common cold.
SARS cases now appear to be declining, although the disease still poses a formidable threat. To date, more than 5,300 people have been infected with the virus in more than 20 countries and at least 355 have died from it.
Gaze at a coronavirus under a microscope and its name starts to make sense. The virus appears as an irregular sphere, topped by a "crown" — or in Latin, corona — of spikes, which are actually proteins.
Lai points out all other known viruses belonging to the coronavirus family have not grown in cell cultures. Instead, they require organ cultures to develop. Organ cultures must mimic the internal environment of an organ and are complicated to set up.
Getting a pathogen to grow in a cell culture is much easier and a much more common technique used by researchers in laboratories around the world — including those at the Centers for Disease Control in Atlanta and at Canada's National Microbiology Laboratory in Winnipeg, Manitoba, where researchers first managed to grow the SARS coronavirus from tissue samples taken from patients.
Four days after that breakthrough, Dutch scientists were able to conclusively show monkeys infected with the virus developed the disease. This was also unusual, Lai says, since coronaviruses don't normally develop in monkey cells.
"It was serendipity that the virus grew very well in these laboratory settings," said Sam Katz, a professor of infectious diseases at Duke University School of Medicine in Durham, N.C.
Katz points out HIV was notoriously difficult to grow in culture.
Good fortune aside, scientists say it's unlikely anyone would have been able to identify the SARS virus so quickly, if not for a deft collaboration effort led by the World Health Organization.