As the threat of bird flu spreads around the world, the big question on the minds of scientists around the world is if -- and when --- the virus might mutate to allow it to be transmitted from birds to humans. VOA's Cathryn Curtis reports on what some scientists in the U.S. are predicting.
Bird flu has now been confirmed in more than 40 countries around the world, and health officials are scrambling to prevent the virus from spreading.
Nearly 200 people have been diagnosed with bird flu and more than half have died from it so far. They caught the virus from exposure to chickens and ducks and birds. The bird flu virus can't spread among humans... yet.
Dr. Robert Webster collects and studies samples of the virus in his Memphis, Tennessee lab. He says chances are good that the virus will mutate and jump from birds to humans. "[There are] about even odds at this time for the virus to learn how to transmit human to human."
If that happened, a deadly pandemic could quickly spread around the world.
Dr. Webster says we need to be prepared. "We can't accept the idea that 50 percent of the population could die. I think we have to face that possibility. I'm sorry if I'm making people a little frightened, but I feel it's my role."
Dr. Jeffrey Taubenberger, of the Armed Forces Institute of Pathology, says there is a frightening historic precedent from 1918. "The risk of the current bird flu is that this virus might be actually going down the same path as the 1918 virus."
Dr. Taubenberger led a team of researchers who decoded that virus. They determined it mutated from a bird flu, but they're not sure where or when that happened. He says today's bird flu virus, called H5N1, shows some similarities to the 1918 virus. He adds, "The H5 viruses, especially some of the more recent ones, share some of those mutations, suggesting that they might be acquiring some changes that would make them more easily adapted to humans. So that's a very worrisome situation for us."
No one knows how many mutations it would take for the virus to jump to humans, when it would happen, or the biggest question of all -- if it will happen.
Nonetheless, Dr. Anne Moscona spends her days searching for new types of anti-virals that would prevent and slow the spread of a human-transmitted bird flu and says there is a chance that the virus may not be able to jump to humans.
"It may not do it. There may just be too many changes. The virus may not be able to be a human virus,” but adds, “I don't think that once we have human to human transmission, it's going to be possible to contain it."
So the scientists work around the clock, hoping the virus doesn't mutate, but preparing for the worst.