Study Finding It Nearly Impossible For Airline Passengers Wearing Masks To Catch COVID-19 Was Based On 'Bad Math'

A Garuda Indonesia Boeing 373-800 NG with a new face mask design as part of a campaign to promote the wearing of face masks amid the COVID-19 coronavirus, is parked at the airport in Tangerang on October 12, 2020.
A Garuda Indonesia Boeing 373-800 NG with a new face mask design as part of a campaign to promote the wearing of face masks amid the COVID-19 coronavirus, is parked at the airport in Tangerang on October 12, 2020.
Image: Photo by ADEK BERRY/AFP (Getty Images)

A study of COVID-19 infection rates on airplanes by the Department of Defense and United Airlines concluded that the risk of masked passengers being infected by the virus while flying was “virtually non-existent.” A lot of people thought that sounded fishy, and it turns out an infectious disease doctor who ran a similar study is one of those doubters.


The DoD/United study, announced last week, involved using sensors to detect particles expelled in the simulated coughs and breaths from a mannequin’s head. The DoD and United ran 300 tests in a little over six months on a United airplane. The airline and the International Air Transport Association gleefully presented their findings last week. From ABC:

“99.99% of those particles left the interior of the aircraft within six minutes,” United Airlines Chief Communication Officer Josh Earnest told ABC News. “It indicates that being on board an aircraft is the safest indoor public space, because of the unique configuration inside an aircraft that includes aggressive ventilation, lots of airflow.”

In late September, major U.S. airline CEOs said their employees were reporting lower rates of COVID-19 infection than the general public.

“At United, but also at our large competitors, our flight attendants have lower COVID infection rates than the general population, which is one of multiple data points that speaks to the safety on board airplanes,” United Airlines CEO Scott Kirby said during a Politico event.

Last week, the International Air Transport Association (IATA) released new research, saying the risk of contracting the virus on a plane appears to be “in the same category as being struck by lightning.”

Wow! Those rates are crazy low, man. The IATA also said its findings “align with the low numbers reported in a recently published, peer-reviewed study by Freedman and Wilder-Smith,” according to Reuters.

That was news to U.S. infectious diseases specialist David Freedman, who called the findings encouraging, but said the conclusions drawn by the IATA were based on “bad math.” Dr. Freeman told Reuters:

“They wanted me at that press conference to present the stuff, but honestly I objected to the title they had put on it,” the University of Alabama academic told Reuters.

“It was bad math. 1.2 billion passengers during 2020 is not a fair denominator because hardly anybody was tested. How do you know how many people really got infected?” he said. “The absence of evidence is not evidence of absence.”

The IATA claims that out of the 1.2 billion airline travelers, only 44 contracted COVID-19 on an airplane. I’m not an infectious disease specialist, but that does sound pretty suspect to me, just on its face. It’s a pretty ludicrous assumption to make. While the IATA told Reuters it never said the 44 out of 1.2 billion passengers figure was a “definitive and absolute number” governments are now being fed this faulty statistic in an attempt to get restrictions lifted:

IATA maintains that its calculation is a “relevant and credible” sign of low risk, a spokesman said in response to requests for comment from the organisation and its top medic Powell.

“We’ve not claimed it’s a definitive and absolute number.”

The head of British Airways directly invoked the 1-in-27 million ratio to press for a lifting of quarantines on Monday.

“We know public safety is key for the government, so it should be reassured by IATA’s new figures,” Chief Executive Sean Doyle told a UK aviation conference.


Well, at least the government will feel reassured.

Managing Editor of Jalopnik.


I mean, even if the IATA’s take on the study is wrong, I see nothing in this article which says the original study by United and the DOD was flawed in any way, which means they are likely correct in the high safely of airplanes due to extremely high air circulation. Just because the data as far as how many people are infected is not properly collected or reported doesn’t mean that the DOD study doesn’t seem to support that this is no more dangerous than going shopping.  I think your headline is at least as clickbaiting and incorrect as the IATA’s take on the original study is.