(CNN) – If your Thanksgiving trip includes a flight, you could run into conflict: is it safe to sit elbow to elbow with strangers on a plane during the pandemic?
It’s hard not to feel at odds with vacation flights.
Airlines are offering travel deals this season, and many of us haven’t seen much, if any, extended family members this year. The latest science provides both reassurance that it is relatively safe to fly and warnings of what can go wrong.
First, the reassurance
Harvard researchers say more research needs to be done on air travel and the spread of coronavirus.
Daniel Slim / AFP / Getty Images
A Harvard University study published Tuesday used computer models to check airflow in aircraft cabins. The specialized ventilation systems on board filter out 99% of the viruses in the air. It was funded by airlines, aircraft manufacturers, and airports, but Harvard researchers insist it didn’t affect their findings.
Researchers at the university’s TH Chan School of Public Health found that although air is returned to the cabin, it goes through high quality filters first. And virus drops from one passenger are unlikely to infect another because the airflow is “downward”.
“This ventilation effectively counteracts the proximity that travelers are exposed to during the flight,” said their report.
However, the ventilation system alone is not effective. Harvard researchers described masks as a vital ingredient in travelers’ health and recognized the role of disinfecting and self-screening passengers for Covid-19 symptoms.
The “multi-layered approach with gate-to-gate ventilation reduces the risk of SARS-CoV-2 transmission on board aircraft among other routine activities during the pandemic such as grocery shopping or eating,” the study says.
The computer modeling at Harvard was in line with another recent study by the Department of Defense that used mannequins with surgical masks and particle detection devices on Boeing 767 and 777 jets. Thanks to the masks and efficient ventilation, the risk of transmission was low.
Harvard researchers described the wearing of masks as a crucial part of the safety of travelers in airplane cabins, but no longer called for a state mask mandate on board flights.
Anthony Wallace / AFP / Getty Images
What can go wrong?
On the other hand, a study published by Irish researchers shows what can go wrong on board even if precautionary measures are taken.
By tracing contracts, public health officials in Dublin and other cities linked 13 cases to a single passenger on a seven-hour international flight this summer. Less than every fifth seat was occupied. None of the travelers were known for not wearing a mask on the flight.
How did that spread?
“Aviation exposure opportunities include flight during overnight / pre-flight transfer or an unknown pre-flight detection,” the researchers wrote. A traveler could have picked up the virus from a family member. Two others stayed in airport lounges for several hours.
For others, “in-flight transmission was the only common exposure,” they concluded, noting that “four of the flight cases did not sit next to another positive case, made no contact in the transit lounge, and wore face masks” on the flight and would not be as tight Contacts apply. ”
The laboratories have classified the cases as originating from the same strain.
The Irish researchers recommended that authorities improve contact tracing, and Harvard scientists encouraged people to minimize mask removal – for example while eating or drinking – on the fly.
Harvard researchers are already turning to other parts of the travel experience when people gather without the aircraft’s ventilation system, such as airport lounges and security lines.