Fact Check

Is Ebola Now Airborne?

Have the CDC and CIDREP admitted that Ebola is now airborne?

Published Oct. 9, 2014


Claim:   The CDC and CIDRAP have admitted that Ebola is now airborne.


Example:   [Collected via email, October 2014]

The CDC is forced to admit that Ebola is airborne.


Origins:   In the summer of 2014, rumors began to circulate in e-mail

and across a number of blogs that the Centers for Disease Control had admitted the Ebola virus had mutated and become airborne. Fears about Ebola and its mode of transmission escalated after the CDC confirmed a patient in Dallas tested positive for the disease in late September 2014. The patient, Thomas Eric Duncan, died on 8 October 2014.

On 6 October, CNN published an article about the possibility of Ebola mutating. The network quoted director of the Center for Infectious Disease Research and Policy at the University of Minnesota Dr. Michael Osterholm on the potential for airborne Ebola:

It's the single greatest concern I've ever had in my 40-year public health career. I can't imagine anything in my career — and this includes HIV — that would be more devastating to the world than a respiratory transmissible Ebola virus.

On 6 October 2014, the World Health Organization (WHO) released a situation assessment reiterating what scientists know thus far about how Ebola is transmitted. The WHO noted that no evidence to date supports the belief that Ebola is airborne and did not indicate in any fashion that rumors suggesting otherwise had any merit:

Ebola virus disease is not an airborne infection. 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.

Common sense and observation tell us that spread of the virus via coughing or sneezing is rare, if it happens at all. Epidemiological data emerging from the outbreak are not consistent with the pattern of spread seen with airborne viruses, like those that cause measles and chickenpox, or the airborne bacterium that causes tuberculosis.

Theoretically, wet and bigger droplets from a heavily infected individual, who has respiratory symptoms caused by other conditions or who vomits violently, could transmit the virus — over a short distance — to another nearby person.

This could happen when virus-laden heavy droplets are directly propelled, by coughing or sneezing (which does not mean airborne transmission) onto the mucus membranes or skin with cuts or abrasions of another person.

WHO is not aware of any studies that actually document this mode of transmission. On the contrary, good quality studies from previous Ebola outbreaks show that all cases were infected by direct close contact with symptomatic patients.

According to the WHO, no known leaps of a similar nature have occurred with viruses that affect humans:

Scientists are unaware of any virus that has dramatically changed its mode of transmission. For example, the H5N1 avian influenza virus, which has caused sporadic human cases since 1997, is now endemic in chickens and ducks in large parts of Asia.

That 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.

This kind of speculation is unfounded but understandable as health officials race to catch up with this fast-moving and rapidly evolving outbreak.

CDC Director Thomas Friedan addressed rumors of airborne Ebola during a phone call with reporters on 7 October. Friedan acknowledged concerns about such a development and said:

"The rate of change [with Ebola] is slower than most viruses, and most viruses don't change how they spread," he said. Frieden is unofficially spearheading the U.S. response to Ebola.

"That is not to say it's impossible that it could change [to become airborne]," he continued. "That would be the worst-case scenario. We would know that by looking at ... what is happening in Africa. That is why we have scientists from the CDC on the ground tracking that."

Speaking to Scientific American, infectious disease expert William Schaffner of Vanderbilt University dismissed speculation over airborne Ebola as an irrelevancy:

We have so many problems with Ebola, let's not make another one that, of course, is theoretically possible but is pretty way down on the list of likely issues.

In mid-October 2014 many social network users and web sites were citing a supposed report from Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota proclaiming researchers there had determined that "Ebola is now airborne." However, CIDRAP did not actually report that information:

Ebola anxiety spread rapidly on social media when inaccurate articles and tweets claimed that University of Minnesota infectious disease experts had determined the deadly virus has become airborne — a claim quickly shot down by the U.

A Twitter user with the name @UnivMinnNews, which uses the U logo but is not an official university account, spread the claim — citing an article in the alternative news site Inquisitr. That story cited a commentary posted on the website of the U's Center for Infectious Disease Control and Policy (CIDRAP).

The published commentary, however, doesn't make that claim, U officials pointed out. It only states that "people should understand the potential for a virus to become airborne." And while it was posted on the CIDRAP website, it was written by an unaffiliated researcher from Chicago.

"CIDRAP is not saying [Ebola] is airborne," spokeswoman Caroline Marin said. "There is always the possibility that diseases can mutate."

The commentary in question made tentative, speculative statements, such as "the Ebola virus has the potential to be transmitted via infectious aerosol particles" and "there is some experimental evidence that Ebola and other filoviruses can be transmitted by the aerosol route" (based on studies involving monkeys and intra-species transmission); it did not definitively state that "Ebola is now airborne" or offer proof that any humans have contracted Ebola through airborne transmission.

Last updated:   16 October 2014


    Cohen, Elizabeth.   "Ebola In The Air? A Nightmare That Could Happen."
    CNN   6 October 2014.

    Maron, Dina Fine.   "Fact or Fiction?: The Ebola Virus Will Go Airborne."

    Scientific American.   16 September 2014.

    Olson, Jeremy.   "University of Minnesota Knocks Down Claim of New Ebola Risks."

    [Minneapolis] Star Tribune.   16 October 2014.

    Viebeck, Elise.   "CDC: Airborne Ebola Possible But Unlikely."
    The Hill.   7 October 2014.

David Mikkelson founded the site now known as snopes.com back in 1994.