Mikel Livingston

mlivingston@jconline.com



Echoing an oft-repeated mantra these days concerning the spread of Ebola, a medical expert testified at a congressional hearing last month that it's "incredibly unlikely" the virus will mutate to become airborne.

"A virus that doesn't replicate, doesn't mutate," Dr. Anthony Fauci, of the National Institutes of Health, the federal government's top medical research agency, told members of the U.S. House Foreign Affairs subcommittee Sept. 17.

Not quite, countered a Purdue University medical researcher.

David Sanders, an associate professor of biological sciences, said that to discount the virus' potential to become airborne is dangerous.

"I don't want people to get worried right now, but for people to say there's zero chance is simply incorrect," Sanders said. "It's not something to be dismissed."

Infectious disease experts agree that evidence suggests the virus currently spreads through contact with bodily fluids and not through the air.

"Ebola virus disease is not an airborne infection," according to the World Health Organization. "Airborne spread among humans implies inhalation of an infectious dose of virus from a suspended cloud of small dried droplets. This mode of transmission has not been observed during extensive studies of the Ebola virus over several decades."

Sanders didn't dispute that stance. It's medically inaccurate and disingenuous, however, to dismiss research showing that Ebola could actually mutate to become airborne.

"I can't put a number on it, but I can tell you it's a non-zero number," Sanders said of the odds of Ebola spreading through the air. "The longer it persists, the more cases there are, the more likely it is."

The debate comes amidst what the Centers for Disease Control and Prevention has called the largest Ebola epidemic in history. In the past month, the virus has gripped three West African countries — Guinea, Liberia and Sierra Leone — resulting in more than 7,000 people diagnosed with Ebola, with nearly half of those succumbing to the disease.

The outbreak has sparked debate in the U.S. over the danger the virus poses to Americans. On Sept. 30, officials identified the first case of Ebola in the U.S. in a patient that had traveled into country from Liberia. Another patient was diagnosed with Ebola in Texas earlier this week.

Sanders said the confusion began with a New York Times Sept. 11 editorial, "What we're afraid to say about Ebola," by Michael T. Osterholm that recounted possible scenarios following the outbreak.

"The second possibility is one that virologists are loath to discuss openly but are definitely considering in private: that an Ebola virus could mutate to become transmissible through the air," Osterholm wrote.

In response to that article, Sanders said, government officials took a hard-line stance to assure the public Osterholm was off the mark. But the move seemed to have confused the public, with many unsure of whom to believe.

Sanders said there are no signs the virus is currently airborne, concurring with the CDC's stance. Rather, noted Sanders, it has the potential to be at some point down the line. Either way, Sanders urged the government to address all possible scenarios and not make it seem as if it's sweeping things under the carpet.

"The reaction to (Osterholm's article), which was said by prominent people, was no, it's not possible," Sanders said. "I believe we have to be truthful with the public."

In 2003, Sanders and a group of researchers from the University of Iowa found that the Zaire strain of Ebola has the potential to enter a person's airway, leading to infection.

Then there's the Reston strain of Ebola, a version Sanders said is closely related to the Zaire strain, which has already been known to be transmitted through the air among pigs.

So, bottom line, the longer the disease lasts and the wider it spreads, the closer it'll be to becoming airborne.

"The message is the longer the international community does not take action, the higher the probability," Sanders said. "If (the odds) were truly zero — like with HIV — then that wouldn't be the question."

The Associated Press contributed to this report.