Ómicron more than double the risk of contagion on airplanes

Aircraft passengers are two or even three times more likely to contract COVID-19 during a flight since the appearance of the omicron variant, according to the world’s top airline medical adviser.

The new variant is highly communicable and has become dominant in a matter of weeks, accounting for more than 70% of all new cases in the United States alone.

While hospital-grade air filters on modern airliners make the risk of infection much lower in airplanes than in crowded places like shopping malls, omicron is spreading rapidly as more travelers plow through the heavens because of the end of the year holidays and family reunions.

Business class may be safer than economy class given the density of people, he said. David Powell, physician and medical advisor to the International Air Transport Association (THERE IT IS, for its acronym in English), which represents almost 300 operators worldwide. As before, passengers should avoid face-to-face contact and frequently touched surfaces, and people sitting close to each other should try not to remove their masks simultaneously during meals, he said.

Powell, former chief medical officer of Air New Zealand Ltd., spoke to Bloomberg News Tuesday about flying during the pandemic. Here’s an edited transcript.

What are the risks of infection during a flight?

Whatever the risk with delta, we would have to assume that the risk would be two to three times greater with omicron, as we have seen in other settings. Whatever that low risk, of which we are not certain, should be similarly increased in airplanes.

Would it be safer not to fly?

The best protection is to have a complete vaccination schedule and to get the booster shot. The protection that comes with using an extra mask or a special type of face shield or definitely not flying, frankly, is probably less than the benefit you would get from just having the booster shot.

There is a kind of rule of thumb that is beginning to appear, that essentially omicron loses the benefit of a dose of the vaccine. Thus, two doses against omicron have similar protection as one dose against delta. That hasn’t been confirmed by hard science, but it seems to have a rough correlation with what’s emerging in the studies.

Is it safe for healthy passengers if there is an omicron case on the plane?

It’s a closed space, but it’s a leaky box, and we pressurize it by putting a large flow of air at one end and then putting a blow off valve at the other end. So the passengers are in a very high airflow environment. It’s an enclosed space, but it doesn’t seem particularly risky to me, unlike an Irish pub with a fan in the corner, or a gym with lots of people screaming, moaning and sweating.

But any flight you take also involves airports, which are a little less controlled. So yes, there is a risk. What can be done? Vaccination, tests, use of masks, distancing. Are surgical masks better than cloth masks? Probably yes. On average, maybe 10-20%.

Most of the documented cases of spread on flights date back to March 2020, before we had tests, before we had masks, before we organized boarding procedures, before there was a high degree of awareness about not flying if you are not well.

How about leaving the middle seats empty in the rows?

It is incredibly attractive, intuitively. Provides greater physical distance between passengers. But we haven’t seen that really provide much benefit. But if there is a cross airflow from the aisle to the window, or from the window to the aisle, it would be a benefit to the person in the middle seat. It probably wouldn’t benefit the person in the seat next to you very much, because deflection is likely to occur without obstruction from the person in the middle.

What about the children on the flight?

The risk of young children contracting a serious illness from travel is low, just because the risk of COVID serious is very low for children. It is one of the unanswered questions with omicron. The risk is not so much for them. The risk is that they may be infected with a mild illness and not know it and potentially spread it during the journey. And that is a risk. Getting them to wear a mask is difficult. The smaller they are, the more difficult it is.