Is SARS from outer space?
By Lauren Compton
LONDON, England (CNN) -- The SARS virus might have originated in outer space, according to a scientist in Britain.
In a letter to The Lancet medical journal, professor Chandra Wickramasinghe of Cardiff University suggests the virus was introduced to Earth on a comet or meteorite.
Comets are known to contain many organic chemicals as well as water.
But international scientists are still undecided about research from 1996 purporting to show ancient bacterial forms in a meteorite from Mars.
The professor and his team estimate a tonne of bacterial material falls to Earth from space each day.
To support his theory, the professor highlights the unique nature and sudden appearance of SARS in China.
He points to other mysterious modern epidemics like the Plague of Athens and the influenza pandemic of 1917-19 as also originating from the skies.
If the claim is true, travel alerts in China and Canada at the height of the SARS epidemic might not have been enough to stop the virus spreading.
Indeed, the professor warns it could still be circulating in the atmosphere, set to fall anywhere on Earth without warning.
"We should remain vigilant for the appearance of new foci (unconnected with infective contacts or with China) almost anywhere on the planet.
"New cases might continue to appear until the stratospheric supply of the caustic agent becomes exhausted," he said.
However, Professor Wickramasinghe admits there is no hard evidence for his theory, which has been ridiculed by some of his contemporaries.
"I think it is completely nuts," Dr. Anne Bridgen, a molecular virologist at the University of Ulster, told Reuters news agency.
"It has a lipid (fatty) coat on the outside and it would tend to dry out in an atmosphere such as space."
Professor Ian Jones, an expert in virology at the University of Reading in southern England, described the idea as bizarre.
And a spokesman for the World Health Organization told CNN though theoretically possible, there was no evidence to support such a claim.
"I find it hard to believe that it came from outer space. We won't be sending a WHO team to investigate."
Meanwhile, researchers in Hong Kong say they might have traced the SARS to civet cats, a delicacy eaten by some Chinese.
The claim came after a month-long investigation by Hong Kong and Chinese scientists tracking the source of the disease. (Full story)