Is it safe to fly right now? As an airline industry beat reporter, I get that question often during these days of pandemic.
Some people just assume that airplanes are dangerous Covid-19 vectors. One relative told me recently that if I wanted to fly from Denver to Kentucky for a visit I'd be expected to quarantine upon arrival. Better, she said, to meet somewhere in-between via automobile.
Indeed, unease about flying is rampant these days. An early August Gallup poll found that 52% of American adults who flew at least once each year before the pandemic now say they would not be comfortable flying.
In one sense, such concerns are not baseless. There's no doubt that flying isn't as safe as just staying home. And I tell people that.
But just how dangerous is it? Not very, the existing data suggests.
In a study released Aug. 2, Arnold Barnett, an MIT statistics professor whose emphasis is health and safety, estimated that flyers have a 1-in-4,300 chance of catching Covid-19 on a full flight and a 1-in-7,700 chance of catching the virus when middle seats are blocked.
The analysis, which was released without formal peer review, used as its baseline a U.S. domestic flight of two hours in length during late June, when the virus was spiking across much of the country. It also assumed all passengers would be masked. Barnett estimated Covid-related mortality risks per flight at between 1 in 400,000 and 1 in 600,000.
Such death risks, he wrote, are "comparable to those arising from two hours of everyday activities during the pandemic."
Meanwhile, documented cases of transmission on planes are scant. As of the last week of August, IATA said it was aware of fewer than 20 such incidents involving less than 50 passengers.
Likely, the actual numbers are substantially higher, but measures to contact trace airline passengers have been far from comprehensive. For example, Reuters reported in late August that the Trump administration's push to require airlines to gather contract tracing data from arriving international passengers had stalled amid privacy concerns.
One peer-reviewed study that does address in-flight transmission looked at the aftermath of a March 9 flight between Frankfurt and Tel Aviv, which carried seven passengers who tested positive for Covid-19 immediately upon arrival.
The study's four authors determined that these seven individuals likely transmitted a total of two cases to other passengers, though even those transmissions may have occurred before or after the flight. The authors also noted that additional transmissions could have occurred, since they were unable to contact seven of the flight's 102 passengers.
"The airflow in the cabin from the ceiling to the floor and from the front to the rear may have been associated with a reduced transmission rate. It could be speculated that the rate may have been reduced further had the passengers worn masks," said the study, which was published in the journal Public Health.
These days, airline passengers around the world are mostly masked, except when eating or drinking. U.S. carriers have slowly come around to strictly enforcing mask mandates.
Airlines are also implementing enhanced cleaning protocols between flights. And as the German authors alluded to, their aircraft are equipped with hospital-grade air filters.
Still, flying involves plenty of touch points and often plenty of face-to-face interaction, including at airports. So, when people ask me if it's safe to fly, I say yes, but conditionally. It's not without risk, like so many activities these days. But that risk is far less acute than many imagine it to be.