New CDC Study Promotes Blocked Middle Seats On Planes, But Doesn’t Say What Most Think It Says

You’re going to see a lot about a new CDC-released study that suggests blocking middle seats is important protection for air travel during the pandemic. However the coverage is going to be very misleading.

All that the new research tells us is that being a bit farther away from someone infected with the virus is probably better than being right next to them, which we already know.

However here’s a typical tweet from a CNN correspondent.

This Study Doesn’t Model Covid-19 Infection At All

The first and most important thing is that the study is very explicit that it is not modeling virus transmission at all, just exposure (“It is important to recognize that the current study addresses only exposure and not transmission”). So any reporting that suggests a reduction in the number of Covid-19 cases from blocked middle seats is using the research wrong.

Researchers used spray bottles in an airplane cabin mockup to disperse bacteriophage MS2, which is a single strand RNA virus similar to a norovirus. A five-row section of a Boeing 737 fuselage, and an 11-row mockup of a Boeing 767 cabin, were used. These didn’t have engines, so actual cabin filtration was replaced by “conditioned air in the laboratory.”

What The Study Actually Tries To Show

Aerosol dispersion was measured and the researchers developed a model for whether someone would be exposed in a the cabin. In other words, they built a model to see how much distance would matter for exposure if you were near someone who was a source of the virus.

Of course right now perhaps 1 in 200 Americans are actively infected with the Covid-19 virus. (Based on a rough estimate of the number of actual infections versus identified infections and an average length of time infected.) A majority of those won’t spread the virus to others.

So if there was someone actively infected on one out of every two or three flights – it’s not likely that many, because some infected people will be less likely to fly because of symptoms – then a “single passenger who was in the same row and two seats away from the SARS-COV-2 source, rather than in an adjacent middle seat” would see a “23% exposure reduction.”

In other words, a blocked middle seat might help those seated around the infected person a little bit, but the piece tells us nothing about how much this changes the risk of spreading the virus.

Mask Wearing Isn’t Accounted For In The Research

The study talks about the rate of cabin air refresh and use of HEPA filtration, but uses that to assume aerosols are limited to spreading several rows from an infected passenger. The study doesn’t measure the extent to which those measures are preventive of infection. And it doesn’t appear to take into account the downward direction of air flow.

It also doesn’t factor any role that masking plays in reducing virus exposure or infection, and doesn’t consider at all to what extent vaccination matters for whether blocking middle seats presents a public health good or not.

Anti-maskers will also find something to like in the study, which justifies their ignoring the role of masks because “masks are more effective at reducing fomite and droplet exposures than aerosol exposures.” If you’re promoting this study for blocking middle seats, you’re also arguing against the effectiveness of masks against aerosol transmission of a virus.

Transmission Can Happen, It Seems Rare, And Not A Big Issue For The Vaccinated

Covid-19 does seem to spread on planes, but is rare certainly compared to other indoor congregant settings. If you’re vaccinated this probably isn’t something to be worried about. But the study may cause you to want to buy an empty middle seat next to you for your next flight.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. All I know is I get my second shot next week and mid May I’ll be flying several times a month all summer…

  2. At this point, IMHO, they are making things up as they go along. Every other week it’s a new scare followed by another warning. Enough is enough

  3. Everyone needs to stop trying to understand the actual science and just listen to your media and bureaucratic overlords. Be SCARED! Stay SCARED! Stay home, do what you’re told, and don’t question anything! The good people at the government will keep you safe.

  4. The reality is Delta paid experts hundreds of thousands of dollars (perhaps millions!) to tell customers over the past year that sitting in a middle-seat or sitting next to someone in first-class was dangerous and unsafe. Who are we supposed to believe? It seems like many of the experts are on the take, kind of like the experts who once produced reports for big tobacco saying cigarettes weren’t harmful to a smoker’s health. The idea that sitting in a middle-seat on April 30 is dangerous and unsafe but perfectly safe on May 1 is absurd. Delta should have got creative and offered a middle-seat comfort package to customers who wanted the extra space. Heck, why not offer customers an entire row of seats for a certain extra percentage of the original airfare? Air New Zealand and other international airlines do this on some long-haul flights. They call it sky couch or whatever.

  5. So much garbage coming out of CNN. Easy to see through their BS never-ending fear agenda.

  6. While is support measure to reduce the spread (mask, distancing, hand washing and getting vaccinated), the CDC has been a complete failure with the air and cruise travel guidance. The really need stop releasing studies that make them sound like trump’s covid squad ( care to inject some bleach anyone).

  7. Over cautious is way better than careless on covid related policies. Even fully vaccinated person should continue taking all the precautions like before.

  8. I’m a bit surprised since people are flying so freely and so many ARE vaccinated that the industry is not lobbying for getting rid of masks. It seems the people not willing to fly these days ARE the anti-maskers. The airline industry gets them back and then the prices really spike. If AA, for example is not grounding any planes in May without blocking seats and leaving all the people still griping about masks, things will go crazy in the skies when all the people are “released” to fly when they don’t have to wear them. The CDC, for all its right and wrong–a bit of both, let’s face it–at some point will have to admit if we’re all sitting on a place with great filtration vaccinated (which most of us are if we’re going in a crowded space–because I am not nuts), we don’t need their help. And that 100-day mask challenge is almost over. It’s been well over a year. Israel is probably at herd immunity. We may not be there YET, but you keep saying we are close and I agree. Those skies will be crowded soon. Sort of a scary thought!

  9. @ Gary — I’m sure this new study will be used to justify the next $50 billion theft from the American taxpayers. Hell, call it infrastructure, and maybe the government can hand out $1 trillion to these crooks.

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