No, Flying After Vaccination Isn’t Like “Walking Into A Fire”

Michael Osterholm, who directs the Center for Infectious Disease Research and Policy at the University of Minnesota, offered a scare story about flying while vaccinated during the pandemic on NBC’s Meet The Press,

[T]he doctor said this about traveling after being vaccinated. And it’s terrifying: “Let me just give an example on the airplane flight. When you get vaccinated, it’s like buying a fireproof suit that works 90 to 95 percent of the time. But it doesn’t work all the time. So why want to walk into a big fire if you don’t have to? So what they are basically saying is, ‘Yes, if you are vaccinated you can start opening up a lot of things in your life that you couldn’t do before.’ But now, if you know you’re going to be walking into a fire, why do it?”

But that’s not what the effectiveness data means. When we talk about a vaccine that is 95% effective against symptoms (90% effective against asymptomatic cases, i.e.. being a carrier) that is in comparison to someone that is not vaccinated. It tells us the reduction in risk that follows vaccination.

One common misunderstanding is that 95% efficacy means that in the Pfizer clinical trial, 5% of vaccinated people got COVID. But that’s not true; the actual percentage of vaccinated people in the Pfizer (and Moderna) trials who got COVID-19 was about a hundred times less than that: 0.04%.

What the 95% actually means is that vaccinated people had a 95% lower risk of getting COVID-19 compared with the control group participants, who weren’t vaccinated. In other words, vaccinated people in the Pfizer clinical trial were 20 times less likely than the control group to get COVID-19.

Saying a vaccine is 95% effective doesn’t ‘fail 5% of the time’. Someone that takes a 95% effective vaccine should have a 95% lower likelihood of catching the virus than someone who is not vaccinated. And someone who isn’t vaccinated doesn’t have a 100% risk of getting it, either, even when exposed.

Since early in the pandemic we’ve known that most people who become infected do not spread the virus. Instead we get a small percentage of people that are infected responsible for a large number of infections through superspreader events. Living at home with someone that has Covid-19 gives you less than a 50% chance of getting it yourself.

Even if that wasn’t true, and there was a Covid-19 positive person on a flight, not everyone on board is at equal risk due to variation in proximity and immune response.

Over the weekend CNN ran a piece making a similar error, that a 90% effective vaccine “translated into reality, that means for every million fully vaccinated people who fly, some 100,000 could still become infected.”

With an average of 1.4 million people per day passing through airport security over the past week, that would imply 140,000 Covid-19 infections per day just from air travel in an entire country with a 7-day average of just shy of 70,000 reported cases. Put another way, if there are twice as many infections as cases, then every infection in the country would relate to air travel.

Yet air travel is an indoor congregant setting, it’s a safer one than most indoor dining in your home town because of HEPA air filtration and downward air flow. It’s possible to get Covid-19 on a plane, but it’s rare.

CNN edited the piece, and this false claim about air travel has been removed, with the following correction,

A previous version of this article incorrectly extrapolated vaccine efficacy and the probability of becoming infected with Covid-19 aboard airplanes. The risk is much lower than stated in the original version.

It’s easy to misunderstand what effectiveness data means for a vaccine. What the Pfizer and Moderna trials showed was that over a 3 month period, vaccinated people had a 0.04% chance of contracting Covid-19. You can extrapolate, then, to an extremely small chance on a given day.

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. The sooner the people understand that this is not about virus or anything related to it. Its about the power and the way to control things. Once politicians get a hangover they will never leave it.
    Its so funny how these so called science experts do not seem to conduct any research regarding ones mental health for a long closure. All the way from 2 year old child to a very old people are affected mentally by this and the longer we delay the longer we will feel the effects and the more numbers will be affected.

  2. I’ve been vaccinated and follow local requirements on mask, distancing etc but so damn tired of the medical “experts” (and I was in the medical industry for over 30 years) that are continuing to scare monger people. Sunday Fauci said he didn’t think dining in a restaurant was a good idea.

    Everything has risk people! It is all about risk tolerance and trade offs. Personally I have continued to travel (more car trips than flight until recently), visited casinos (was in Las Vegas last week) eaten in restaurants and lived my life. If people want to continue to hunker down go for it but most, especially after being vaccinated, won’t. Frankly if I couldn’t live the life I want I’ve perfectly fine getting COVID and dealing w whatever comes. Being afraid and not doing the things you love is no life IMHO.

  3. Having taught college level statistics for years I am not surprised. Most people don’t understand how to interpret data. That’s been well shown in this pandemic where folks do not understand that scientists don’t have hard and fast numbers and in fact revise their estimates, and sometimes their models, as new information is developed. But that is exactly how statistics-based research works. You have probability ranges, not absolutes, and do the best you can with what you’ve know when considering what is most likely to happen.

    So it’s easy for newspeople and politicians to extrapolate to worse case scenarios rather than consider higher probability events. The opposite also happens when people brush off results that they don’t want to hear, calling them “theories” and then are surprised by bad outcomes. And incidentally if you want to see a good example of how folks often don’t know how to handle numbers look at how many people take out loans without understanding compound interest. That’s one area where the schools have really fallen down. If any parents are reading this teach this to your kids before they buy cars or get credit cards.

  4. I’m about as liberal as they come and can’t phantom why so many seem to want to stay in this locked down state now that we have an effective vaccine. I can see if you have yet to receive the shot or have some medical reason. But as someone who’s been team mask the whole time I can’t wait to be able to burn them!

  5. I flew over half a dozen times last year, cross-country, followed safety protocols and got vaccinated starting in early February (I helped out at an AZ Pod, so you get vaccinated early) and was fully vaccinated by the end of February. Out of respect for others, I still wear and will continue to wear a face mask, wash hand more frequently and keep my distance. Once we hit herd immunity, then I will begin to return. . .slowly. . .to normal.

    If more people would just do what’s right and stop making this political, listening to washed up formerly rich reality TV presidents or racist hate group, we will get out of this and save thousands of lives. Ignorance, mis-information and selfishness is the true pandemic we need to conquer.

  6. The point is that if you have been vaccinated, it is quite safe to travel. And if you want to feel even more secure, just wear a mask. It won’t get any safer than that.

  7. I’ve disagreed with Gary about plenty over the years, but his takes about travel and life in general post-vaccination have been incredibly well reasoned.

    We can’t be locked in our houses forever, getting back into a more normal life after vaccination is appropriate for most folks level of risk tolerance.

  8. There are so many scientifically and mathematically incompetent people trying to write about COVID. They are often well meaning but spread nonsense.Thanks for the rational analysis. We need to get people vaccinated and let the vaccinated live normal lives, including travel.

  9. @ Gary — This is a great example of why I stopped watching TV after Satan moved from 1600 Pennsylvania Ave to Mar-a-Lago on January 20, 2021.

  10. Wait . . . Gary is disagreeing with CNN and NBC on something? I thought liberals are supposed to eat whatever trash they pitch?
    I appreciate the independent thought and agree with Gary!

  11. Can we also note how many orthopedic surgeons and urologists have suddenly become TV covid experts?

    in addition to the good words from BlackHill and drrichard, let’s also note that covid is still much more random than other diseases – perhaps it is the sheer number of people that is creating significant variability in everything from infectability to post infection syndromes – but far too many “experts” proclaim that they have the authoritative answer right now – and too many people want exactly that.

  12. With this virus that has never been experienced before (and now the variants) how can anyone expect the doctors and scientists or any “experts” to be 90 or 100% correct about everything? All we can do is try to be calm and listen to their suggestions. Anyone have a better idea?

  13. It has been nice to read so many responses where there is no name-calling and all (so far) agree and appreciate what Gary has shared. Myself included.

  14. @Juan – I think it’s fair to expect that if someone is going to go on tV and talk about what vaccine effectiveness data is, or write a piece for CNN on it, that they should know how effectiveness data is reporting and what it means. It’s math, so you don’t have to have prior experience with this virus to do that.

    There’s no question that it’s difficult to make predictions, especially about the future. But that’s not what’s at issue here. Since there’s so much bad information out there, including from supposed experts, about how to understand what’s reported on vaccine effectiveness it seemed like a discussion was warranted.

    …..your papers please.

  16. There is always risk. Having been vaccinated, I’m still wearing a mask. I just did 9 days in Las Vegas(house hunting). I constantly wear my mask, except while eating. I sanitized my hands, every time I saw a hand gel station. There is always a risk of something, anything happening.

    The real issue is that huge amount of the population who won’t get vaccinated. Until these people get vaccinated, Covid will reign. Because of this reason, any amount of infections, increases the chances that a new mutation will occur. With every mutation that occurs there is the risk that the current vaccines will not work. Until people understand that all their egotistical games will ultimately hurt everyone. We will then continue in this ebb and flow of infection, with no end in sight.

  17. Flown probably 150,000 miles since Jan 2020. 6 continents, 30+ countries.

    Non vaccinated (don’t plan to). Don’t wash hands more often, eat indoors at restaurants.
    Go to open air markets, eat with locals, eat street food.
    Rent cars, hotels every night.
    Busses, minibuses, taxi and ubers.

    No issues.

    What is the common theme?
    I don’t watch the news, I don’t listen to what the government mandates, and I live my life.
    I’m not scared, and I don’t live my life as a scared peasant under the foot of some benevolent government ruler.

    Maybe other people are waking up too.
    There is a life to be lived people. If you’re life is one you’re willing to put on hold – purely out of irrational fear – well, that’s just sad :/

  18. Thank you for this PSA.

    You badly need to do a blog entry that says “no, you’re not covered immediately after your first vaccine shot”. Way too many people think they are covered and throw caution to the wind (some ending up catching COVID!), when in reality the mRNA vaccines offer ZERO protection for the first 12-14 days after the first shot and it’s only after 2 weeks after the second shot that you get to 94-95% efficacy (similar curve exists for the J&J).

    Please, please, please do such a blog post PSA!

  19. @Gene I guess I missed it. So many good comments I guess I blocked it. Will go back and read again but disappointed.

  20. @garyleff
    “most people who become infected do not spread the virus”
    SO WHAT?
    How is it spreading? From the uninfected? From COVIDs version of Typhoid Mary?
    Come on, you’re better than this, aren’t you?
    With social distancing, perhaps an argument can be made that someone who “magically” gets infected isn’t infecting others because he/she isn’t near others, but, that said, the person in question managed to get COVID, so….

  21. @George… LOL… That entire post is pretty entertaining.
    Thank you for supplying some of my daily dose of humor.

  22. covid19 is a serious situation, and many people are still unvaccinated, in our country and around the world, so it’s not over yet. But if you are vaccinated by this point, go for it, do whatever you want. (I am not, yet, but will be in a month). The likelihood that you would get sick or spread the virus is bound to be incredibly low, as Gary explained. I am also exasperated by people who seem to have pandemic-related stockholm syndrome and are terrified to return to normal life.
    The reason for staying with the masks for a few more months is simple — to make unvaccinated people or people who can’t get vaccinated or couldn’t get a spot yet, not feel like outcasts, and therefore encourage those people to keep wearing masks, which is still important at the moment. But we will certainly stop eventually, in the summer or fall.
    While this might change with new mutations, at the moment they all respond adequately enough, to the vaccines we have. There is no reason to assume that the vaccine wouldn’t at least make us partially resistant/less susceptible to new variants (meaning, getting us less severely sick). Certainly these are not arguments for changing our behavior right now — except to get more people vaccinated, so that the virus has less and less “territory” to try out new mutations.

  23. “Since early in the pandemic we’ve known that most people who become infected do not spread the virus.”

    Correction: yes, we knew all that EARLY in the pandemic. Before all the variants that seem to be spreading around the world like wild fires, many of which are several times more transmittable than the original Wuhan virus. Plenty of things we thought we knew have turned into something we don’t.

    Other than that, I agree that traveling while fully vaccinated should be reasonably safe. At least, I really want to believe that ’cause damn…

  24. @George (and others). I get that you want to continue life as is, but I don’t understand why you are afraid to get vaccinated?

  25. @ Juan — if you read enough of George’s assinine posts, I think you’ll see his problem.

  26. @sunviking82

    It is outlets like CNN and people like Osterholm who are spreading ignorance, disinformation and fearmongering. It is scary to think that Osterholm, a professional epidemiologist, could be so mistaken about vaccine efficacy. Either he is ignorant or he is promoting a “noble lie” to try to get the public to behave the way he wants. Neither should be acceptable for a person in his position. I get the impression that you will swallow whatever your overlords feed you. Do you remember when Fauci said not to wear masks?

  27. @sunviking82 You really need to read Gary’s post again; he is completely right.

    @gus Very good logic, however, you are missing the power part of this. No way masks go away due to this.

    Two other scientific facts these so called “experts” always ignore. First, transmission from surfaces is exceedingly low; so what with the obsession on washing hands, etc? (Yes, good for other reasons, but not COVID) They lose credibility with me every time they say this. Second, single mask wearing really does little to protect the wearer… if for the benefit of others. So, folks can scream about masks all they want, but some simply won’t do it. So, why in the hell do we expect vaccinated folks to do it, the least likely to transmit?

    This virus will be endemic and we will get boosters each year. (mRNA vaccines are easy to update) The sooner we accept this and go on with life the better.

  28. What I don’t understand is, if the Gov’t and “experts” are so insistent on everyone getting vaccinated (which I’m for) why do they continue to wear masks and social distance outside when they have all had the vaccine? If you want to give people reason to doubt the effectiveness of the vaccine, they’re doing a good job.
    They should remove their masks and eat indoors and show everyone that once vaccinated you’re pretty much safe from this.

  29. A few points
    a) I have been Osterholm’s podcast listener since early 2020. He is an infectious disease epidemiologist and has been around since 1980s. He was involved in original SARS and MERS pandemics (and a few others). Just go back and listen to what he said back in March 2020 when everyone else was claiming that “this is not a big deal”. He was more accurate with his predictions than anyone else (other than his claim that we will not see vaccine for 2 years)
    b) Osterholm is not afraid to go against the grain. He got a lot of flack last spring when he said that there is no solid science behind cloth masking. Even now, he is highly skeptical about about it (other than N95, obviously)
    c) 95/5% math is sloppy. My guess is that he was trying to make the point and got carried away
    c2) vaccinated people get COVID (not 5%). Vaccinated people get hospitalized with COVID. This is just the fact. If not hospitalized, they may still develop long COVID. Don’t be dismissive about that. This is a nasty long term consequence that can be around for a long-long time
    d) Flying may be safer due to HEPA filter, but you don’t just teleport to the plane. What about TSA lines, jet bridge lines, people on the bus to the car rental, etc. Also, small regional jets do not have HEPA filters
    e) Not sure it matters anyway. People around me (work, neighbors, friends) gave up on the pandemic back in January and back to business as usu

  30. Hi Gary,

    Great columns and information you provide in a very fair and even handed manner.

    You gave a great data analysis of air travel and Covid in this article.

    The doctor you quote, if it is the same person in the link below, gave (IMHO) a very “non real world” view. He has very impressive credentials, but is not listed as being a physician.

    If we, as physicians, utilized his logic and interpretive approach of statistical data, nobody would ever get vaccinated, nobody would have open heart surgery, or myriad other medical or surgical treatments with medication/s, procedures, or surgery. I am a physician and we have a solemn duty to do what is best for the patient/s and to explain the known and possible complications and recommend a course of treatment that considers the whole patient and their needs and desires. True physicians don’t have the option of speaking from an office and not providing the necessary care for sick and injured people. That’s how and why many of us understand that we are but an instrument of a higher power.
    Scare tactics should never be part of the armamentarium of any medical professional, physician or otherwise.

  31. Live in fear if u want Bob. I choose to live life. I am vaccinated and follow the rules but I rarely watch the news anymore and these experts mean nothing to me. Use common sense! There are many ways to die in this world you can’t fully protect yourself so why worry trying.

  32. I think most of you are dead wrong, including Gary.

    Yes, life is full of risk. But FFS its not exponential like C-19 can be. Im reading so many flawed comparisons

    if you get hit by a bus, you arent going to spread that to your family
    if you get cancer you arent going to spread that to your family

    In neither case above will you potentially kill someone you don’t know, without even knowing it.

    Look I was Mr Travel, part of which were the 3+ weekend trips per year I treasured to Gary’s town since the early ’90s.

    Right now I couldn’t care less about that. I am far more invested in making sure my family and their friends don’t get caught up in c-19 and its unknown L-T effects – which is a huge part of the story yet to be written IMO.

    Andy Shuman one of the few not viewing through a completely selfish lens. He nails it:
    “… (that was) before all the variants that seem to be spreading around the world like wild fires, many of which are several times more transmittable than the original Wuhan virus. Plenty of things we thought we knew have turned into something we don’t … other than that, I agree that traveling while fully vaccinated should be reasonably safe. At least, I REALLY WANT TO BELIEVE THAT ….”

    In large part the AWG’s here believing what they want to believe, IMO. Gary, feel free to take my J seat to Qatar from now until the end of time. I’ve got way better things to do.

  33. Hepa filters on planes not designed for viruses, filters size minimum are about 3x too large and also time to refresh and filter total cabin volume is minimum of 3 minutes. So if any single passenger is infected and spreader, then filter capacity is only one breath per 3 minute period. Otherwise over capacity of filtration system design, unless all infected passengers holding breath for over three minute intervals in unison.
    Vaccine effectiveness is also limited by time and the current consensus estimates of three months is common with some speculating that this might stretch out to 6 months before a booster shot would be needed. From 3 to 6 months after first vaccine, there is an increasing likelihood of reinfection and spread , even if no symptoms reappear. That is optimistic hope of duration currently.

    Vaccinations with longer duration vaccines, more accurate rapid testing, and better compliance with mask wearing and distancing practices will all be needed in combination to stop the spread of the virus. Just doing some of these sometimes is unlikely to work, or be effective at any level or altitude. It’s not that complicated.

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