The World Health Organization says its scientists are unaware of any virus that has dramatically changed its mode of transmission.
"For example, the H5N1 avian influenza virus... has probably circulated through many billions of birds for at least two decades. Its mode of transmission remains basically unchanged. Speculation that Ebola virus disease might mutate into a form that could easily spread among humans through the air is just that: speculation, unsubstantiated by any evidence."
Osterholm and other experts couldn't think of another virus that has made the transition from non-airborne to airborne in humans. They say the chances are relatively small that Ebola will make that jump. But as the virus spreads, they warned, the likelihood increases.
Every time a new person gets Ebola, the virus gets another chance to mutate and develop new capabilities. Osterholm calls it "genetic roulette."
"The roots of our Ebola fears", that book chronicles the 1989 outbreak of Ebola Reston, which was transmitted among monkeys by breathing. In 2012, Canadian researchers found that
Ebola Zaire, which is involved in the current outbreak, was passed from pigs to monkeys in the air.
Dr. James Le Duc, the director of the Galveston National Laboratory at the University of Texas, said the problem is that no one is keeping track of the mutations happening across West Africa, so no one really knows what the virus has become.
One group of researchers looked at how Ebola changed over a short period of time in just one area in Sierra Leone early on in the outbreak, before it was spreading as fast as it is now. They found more than 300 genetic changes in the virus.
"It's frightening to look at how much this virus mutated within just three weeks," said Dr. Pardis Sabeti, an associate professor at Harvard and senior associate member of the Broad Institute, where the research was done.
Even without becoming airborne, the virus has overwhelmed efforts to stop it.
Ebola airborne: A nightmare that could happen - CNN.com
