THURSDAY, May 22, 2003 (HealthDayNews) -- The emerging infection known as SARS first struck humans in China, but could the new virus have a more exotic origin?
A team of British and Indian scientists are proposing that the apparently novel coronavirus that causes SARS -- short for severe acute respiratory syndrome -- may have been born in outer space and hitched a ride to this planet on an icy comet passing near the Earth.
"Comets dump material all the time," says Chandra Wickramasinghe, an astronomer and director of the Cardiff Center for Astrobiology in Cardiff, U.K. "Ultimately, all viruses had a space origin and new viruses come from time to time to add to this flora that already exist."
Wickramasinghe is an advocate of "interstellar panspermia," the notion that organisms from space were the starter kit for life on Earth. He and his colleagues claim to have found that a ton of bacteria falls over the Earth every day -- or 20,000 bacteria per square meter -- though those results haven't been confirmed.
As a result, they suggest, microbial space invaders could be the source of plagues and pestilence here, including not just SARS but the flu pandemic of 1917-1919 and the mystery illness that struck Athens in 430 B.C., wiping out nearly a third of the population. "Many of the new diseases that come are strong candidates for this kind of entry onto the Earth," says Wickramasinghe, co-author of a letter proposing the cosmic-SARS theory in this week's issue of The Lancet.
New cases of SARS might continue to appear, the authors write ominously, "until the stratospheric supply of the causative agent becomes exhausted."
Lynn Rothschild, a space biologist at the NASA Ames Research Center, near Palo Alto, Calif., believes it's "absolutely plausible" that organisms from the cosmos seeded life on Earth. However, she says, the idea that SARS came from beyond the atmosphere is, well, spacy.
"It's just not credible," says Rothschild of the Cardiff group's theory. "To be a successful parasite you have to know your system. You can't just go in and invade and expect things to work. The Andromeda Strain, it's just not going to happen," says Rothschild, referring to Michael Crichton's breakthrough novel about an extraterrestrial virus that terrorizes Earth.
Dr. Baruch Blumberg, of Philadelphia's Fox Chase Cancer Center and the first director of NASA's astrobiology program -- which funds research into life beyond Earth and the effects of space on terrestrial organisms -- says the stellar origins of infectious diseases is a hypothesis that's "well worth testing." Yet he's not aware of any evidence to support or reject it.
On the other hand, says Blumberg, who shared the 1976 Nobel Prize in Physiology or Medicine for his work on the hepatitis B virus, ruling the theory in or out would be equally interesting scientifically. "Suppose life isn't found elsewhere. That's also pretty profound."
As of Wednesday afternoon the World Health Organization was reporting nearly 8,000 cases of SARS worldwide, including 666 deaths from the disease.
More information
For the latest on SARS, try the World Health Organization. For more on astrobiology, check out this Web site from NASA.
