A Vaccine Alone Won’t Be Enough To Make Travel Normal Again

Many readers have said consistently throughout the pandemic that they will not travel until there is a vaccine. CNN recently interviewed several people taking this position. I think it’s the wrong paradigm for thinking about future travel both because a vaccine won’t be the cure all many people expect and because travel itself seems pretty safe, the issue is what you find at your destination.

We know a lot more about Covid-19 than we did three and four months ago. Much of what we think we know is still speculative. There’s learning which suggests real optimism, even as the virus spreads rapidly through much of the country (especially the southern portion). But the idea that we’re just hanging in for a vaccine, and once we have one everything goes back to normal, no longer holds up as we learn more about what vaccines against the novel coronavirus can do. At the same time it’s one part of a tool kit that will bring life and travel back to what it once was – and taken together likely even get us most of the way there in the first half of 2021.

Travel Is Safe Now, But You Can’t Do As Much As Before

Business travel isn’t returning this year because it isn’t just flying that needs to be safe (and large companies tend to take a very cautious view putting travelers on the road) but the destination needs to be also, and business travel involves a whole lot of coordination around the idea that travel is safe.

Offices need to be open, or else remote workers won’t be traveling to headquarters, and you can’t go visit a client that isn’t at their office or where their office isn’t accepting visitors. That’s even aside from large gatherings being inadvisable, so conventions and meetings aren’t coming back for awhile. Those get planned pretty far in advance, too.

Planes with HEPA air filtration seem pretty safe, there really haven’t been demonstrated cases of virus spread inflight. If airlines were really a spread vector we’d see a lot of spread that we simply don’t find. IATA acknowledges that a Vietnam Airlines London Heathrow – Hanoi flight probably spread the virus on March 1, but even there it could have happened in the gate area or on the jetway. Millions of people have flown since the start of the pandemic and we just haven’t found evidence of significant spread on airlines.

That doesn’t mean travel makes sense. You may fly somewhere the virus is spreading at a high rate, exposing yourself at the destination. Flying does involve being around more people, in the airport and to and from. And once you get there… will you be let in? It’s not just foreign countries that are limiting entry, several U.S. states are imposing quarantines on arriving travelers from several other states.

If you’re allowed to travel freely to your destination you may find the bars closed (if that’s your thing), restaurant dining options limited, service at your hotel limited, and sporting events and other activities closed too.

And what if you’re exposed to someone who catches the virus while you’re traveling, and you have to quarantine while you’re gone? Then you’re facing additional time away from home, inconvenience (even if you don’t get sick) and additional travel expenses.

Some people are driving long distances to avoid flying, I think that’s a mistake – that air travel is probably safer than driving still. We shouldn’t focus only on one type of risk to the exclusion of others.

Vaccines Aren’t A Silver Bullet

There’s no question we’ll have vaccines, because we already have vaccines. The question is how effective they’ll be and how safe?

That is why clinical trials are proceeding in the U.S. The mRNA approach is new, seems to generate antibodies to the virus, and hasn’t been causing unacceptable levels of side effects, but what happens at scale when used across a huge variety of races, ages, and people with background conditions? We have to find out before making these vaccines widely available.

The Chinese have a vaccination they’re giving to their military and now some state-owned companies too, though it’s probably the least effective among current world candidates. It’s an attenuated virus, and it may help a little and probably won’t have major side effects.

There’s an idea of ‘a vaccine’ as though it’s a binary event, we either have one or we don’t, and that’s the wrong mental model. We’ll likely have several iterations of vaccines, a first generation and then subsequent generations that are more effective.

An initial vaccine might be, say, 40% effective which would mirror last year’s performance of the flu vaccine (the FDA has said their target is 50% effective for approval, though they would consider an emergency use authorization below this threshold). And not everyone will take the vaccine, let’s say we have 50% adoption, just look at the number of people who won’t wear masks and ‘anti-vaxxers’ have been on the rise in recent years.

Vaccines are one tool in a rapidly expanding toolbox that will help fight the virus and bring us back to normalcy, but the introduction of a vaccine – call it winter 2021 – won’t bring everyone back out of the shadows. (This is a prediction, feel free to disagree, though my predictions from early in the pandemic have a pretty good track record so far.)

Even if we have a vaccine candidate determined before end of year, and beginning to be distributed early in 2021, it will take time for production and distribution to fully scale up, even though that’s starting now to some extent. It’ll initially be available to health care workers and politicians and the wealthy and well-connected. It’ll take time for the rest of us to get it. And once it does it’ll reduce spread but not eliminate it. Some vaccinated people will likely still get the virus.

20% Protection From A Vaccine May Be Enough, As Part Of A Portfolio Approach

If 50% of people take a 40% effective vaccine, call it 20% protection. That layers onto the percentage of the population that’s gotten Covid-19 and retains immunity, and the percentage of the population with pre-existing immunity.

This should be enough to keep the virus under control, and though there’s been a lot of media coverage about antibodies wearing off quickly after someone recovers from Covid-19 that doesn’t mean they lose immunity quickly as new research on t-cell mediated immunity suggests: it appears that some number of people already have t-cell mediated cross-immunity from other common cold coronaviruses, and t-cell memory of this virus should reactivate an immune response even after antibodies wane.

How robust these effects are remains speculative, of course – and how immunity will be impacted by future mutations of the virus, though this one seems to be mutating less than many expected – but this research is the best news we’ve had in awhile. Still, as immunity does wane, more people may become vulnerable to infection again in a cycle of maintaining herd immunity.

Fortunately there’s a lot of thinking that herd immunity, which isn’t really just an either-or proposition but about a slowing down of spread as there are fewer people vulnerable to infection, may be achieved or approximated at lower levels of infection than some early estimates had claimed, “20% – 60%” is a wide range but helps explain low infection in New York City even as re-opening continues there. (See this too.)

We’re also seeing new therapeutics – not just the ones that have been broadly covered, but others where trials are underway – and even without those in use yet we’re seeing improved patient outcomes (for instance prognosis for someone on a ventilator is much better than in March). As infections have spread and especially in nursing homes (as we’ve seen this week in Texas) that will mean more absolute numbers of case fatalities, but I’m optimistic that improvements in how patients are treated will mean shorter hospital stays (helping to reduce the strain on health care systems) and that the virus won’t be as deadly when people get it. There’s some evidence suggesting this now, but we’ll have to see whether it continues to hold (and the point is, it should get better in any case better drugs).

The upside here to a gradual return to normalcy as we layer on protections and improvements that allow us to live with the virus effectively is that it means improvements like aircraft and hotel cleaning regimens – which would have been desirable even before the pandemic – probably stick around awhile.

Things Will Get Better Here, But That Doesn’t Mean They’ll Be Better Everywhere

As poor a response, and as widespread as the virus is here in the U.S., it’s hard to imagine that things could become better and safer for travel in the United States before doing so in (some) other countries. But the one area that the U.S. seems to be doing well, along with the U.K. and Germany, is in its biomedical response.

Some combination of pre-existing protection, recent infection, therapeutics and vaccine may suppress the virus to where it’s manageable here in the U.S. and life goes back to something like normal by spring 2021. That doesn’t mean everything is up and running – many events will require long lead times to switch back on, the most vulnerable may still rationally shelter, and habits take time to break too.

If the vaccine comes here and to Europe and North Asia first, what does that mean about travel to parts of South and Central Asia, Latin America and Africa? Availability of the vaccine seems likely to be an issue at least initially.

If you’re considering trips to South America and to Africa, they may not have access yet or for awhile. And that means some activities on the ground may not be fully open, and that since a vaccine won’t be 100% prophylactic you may still become infected during travel. The advisability of medical evacuation insurance coverage may be greater and certainly more top of mind though do due diligence on the terms.

If you disagree with any of this – and there’s plenty here that remains speculative, and as Yogi Berra is said to have said “It’s tough to make predictions, especially about the future” – please say what precisely you think is wrong and offer your reason why so we can have a constructive dialogue about what the markers of going back to normal travel will look like.

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 InsideFlyer.com, 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. @Mak, you said “only a small percentage of non-elderly people are hospitalized”.

    That is factually inaccurate unless you have an extremely broad definition of “elderly”. Official stats in GA right now (where I live, so it’s the stat I know) is 9% of confirmed covid cases age 40-49 were hospitalized. 14% of 50-59. I’m 42, and I’m sorry, but I don’t consider myself elderly, nor do I consider a 9% hospitalization rate to be a “small percentage”. I also don’t think 50-59 is really “elderly” either, but at least the later part of that age band can be argued as the earliest of “elderly” ages.

    Thankfully the death rate has trended down as everyone expected, but I do worry that it will start to climb again as the lag kicks in and many of the current wave of hospitalizations turns into fatalities.

  2. a vaccine alone might not make travel normal; but it is going to most probably be part of whatever the new normal is. Even if there are few regional vaccines of some limited effectiveness and acceptance, it may be necessary to partake if you want to visit this or that part of the world.

    Good post gleff, sounds like you’ve done your “homework” on vaccines of late. what if the more we all learn the greater the uncertainty becomes; and that is the new normal?

    Maybe instead of cleaning/not cleaning tray tables : just do away with them entirely on comercial airplane seats. Dont really need them for food service these days, except long haul.

  3. Gary, it’s true that a vaccine is not a panacea, but your persistent assurances that air travel is safe are not. We might not “see a lot of spread” simply because tracking the origins of an infection is a) very difficult in the first place, b) our tracking capacity is a joke, or c) people decide to keep the history of their travels to themselves either out of embarrassment or for whatever other reasons. And yes, there have been studies that prove you can catch it on a plane — this one (https://www.medrxiv.org/content/10.1101/2020.03.28.20040097v1.full.pdf) follows a story of 12 people catching COVID-19 on one flight, and the trackers didn’t even manage to find everyone.

  4. @Andy Shuman – I’ve read the study and there’s nothing in there I can see that shows passengers getting Covid-19 inflight. I’ve highlighted the February 1 London Heathrow – Hanoi Vietnam Airlines flight that is the best demonstration of it, though even there we don’t know if infections happened inflight versus in the gate area or jetway.

  5. @David Moore – I don’t think there’s going to be one day specifically where before it protective measures stay in place and after that date they’re gone. My model at this point is that there are layers of protection that reduce risk, and there are varying levels of risk. I’m hopeful that we’re back to ‘normal’ with international travel a year from now, though I suspect there’ll still be some residual processes in place. And it probably does make sense for elderly people with comorbidities to take more cautions than before even aside from Covid.

  6. I very much enjoy your posts and usually find them filled with useful information.

    While I appreciate your obvious enthusiasm for travel and flying, your comments in your editorial are heavily colored by that enthusiasm.

    Your point about there not being evidence to point to flying being a potential cause of infection lacks these basic facts:
    1. There is currently little to no pre-flight Covid testing.
    2. There is currently little to no post-flight Covid testing.
    3. Both #1 & #2 are impractical due to our inability to develop an “instant” test.
    4. Based on #2, there is no way to know if someone who travels to another city becomes “Typhoid Mary” at the destination as there is very little tracing.
    5. While our knowledge of Covid is increasing, it is still very basic and we do not understand many aspects of its spread. Our current precautions are at best guesses based on what we think.

    The points I bring up are only part of the reason why traveling with risk levels similar to pre-Covid are a long way off, unfortunately. I wish it were not the case, as my wife and I have travel destinations that are on hold until there are squared away.

  7. I’m skeptical that there will ever be an effective vaccine for C19. It is a Coronavirus. Colds are also viruses and there is no cure nor is there a vaccine for the common cold. Therefore I do not expect to see a vaccine at least not an effective vaccine for the C19 anytime soon. O course I could be wrong and there might be a vaccine but I have no intention of taking it.

  8. @dale, I understand your pessimism, but it’s worth noting that both major SARS viruses and the very similar MERS virus mutate far less frequently than the corona viruses that cause many “common cold” infections. Also, not all common cold viruses are coronaviruses. There’s some reason to worry that immunity from a SARS-CoV2 vaccine will not be long-lasting like vaccines for polio or even tetanus, but if it’s good for at least 6 months to a year and that can be “renewed” with a booster, we can eliminate or reduce severity of a huge portion of infections.

    Conceptually, there is nothing that makes it impossible to create a vaccine for specific viruses that cause the common cold. There’s just not enough benefit to it to justify the cost, especially when there are so many virus types and strains.

  9. As a doctor, I find it difficult to respond to people without a medical background whose arguments are this weak.

    The fundamental problems are unchanged since January:

    1. There is no vaccine for prevention.
    2. There is no effective treatment (apart from a weakly effective remdesivir infusion which can only be given in hospital).
    3. It’s highly contagious.
    4. The true mortality rate has been 1-2% all along. Previously it was skewed upwards due to a lack of testing, now its skewed downwards by younger people transmitting it amongst themselves.

    Gary’s comments on air travel transmission are based on junk science. The US and UK have minimal contact tracing, so the data is pure fiction.

    The only valid data is from hotel quarantine in Australia and New Zealand. And significant numbers of people test negative at 3 days and positive at 10 days, which effectively shows that they either caught it at the airport or on the plane.

    The travel industry obviously claims that air travel is safe. The lesson of hotel quarantine Down Under is that people who didn’t have the virus when they started their journey test positive after it.

    I love travel. I’m a top tier frequent flyer with 2 airlines and my friends and family live in another country. But I’m not foolhardy enough to travel…..until there’s a vaccine.

  10. @DavidF you’re not even correct about the mortality rate, CDC says it’s 0.65% and even that may be slightly high (closer to 0.5%). And there are several solid treatments in late stage trials.

  11. Getting people to accept a hastily approved vaccine may turn out to be difficult. I am certainly not an anti-vaxer but I also will not be a guinea pig for something rushed. There have been numerous reports of successful trials published in inappropriate places with incomplete and misleading information simply to pump up a stock. Some of the authors have been writers with known ties to hedge funds and previous pump-dump involvement. In some cases insiders, including the “vaccine czar”, then sold a large quantity of shares. It will not surprise me if a vaccine gets a hasty emergency approval because it was stockpiled in advance and is in the financial interests of the right people.

    I will be glad to get a vaccine after it is proven over time and we have complete experience with its possible side effects and knowledge of how effective it is and for how long. I’ll let others be the guinea pigs for getting to that point.

    One of our largest problems in the US is a complete lack of trust in our “leaders” and institutions. This problem has roots going back to before covid and the depth of the problem, and reasons for it, are only becoming more clear now that we have a crisis.

  12. @ Gary. Fair post, especially the qualifier “Much of what we think we know is still speculative.” Unfortunate that the bureaucrats and politicians do not recognize this and continue to issue their edicts. Since flight crews are apparently not doing “one and done”, I surmise that either the Wuhan Virus is less lethal to healthy individuals than originally stated, mutated to a virus with symptoms similar to the flu, or that the MASKS, any mask, is extremely effective, which I personally doubt. Regardless, in the words of George Santayana, “Those who cannot remember the past are condemned to repeat it.” This knowledge is evidently sometimes missed in medical school.
    Reminds me of the joke . . . what is the lowest scoring graduate of medical school called . . . Doctor.

  13. @One Trippe – we’ve identified the mutations though and this virus seems to be mutating less than expected (other than the D/G mutation that seems to have made it more infectious), though one suggestion is that it’s been around longer than thought and already made significant mutations, this might also explain the low prevalence throughout much of Southeast Asia (that people may have some immunity from prior spread, and could also explain why 90% of Thai cases have been asymptomatic).

  14. The arrogance of people that have platforms has amazed me during this pandemic. When you get your MD, you can give us advice about health issues. Until then, please stick to your limited platform.

  15. Carolyn – it’s PhD research scientists who know the most on this subject actually, i’m just reporting on what they’re saying as far as Covid-19 goes, my only unique contribution here is the applicability to travel i don’t think i’m the one here being arrogant..

  16. @ Gary. Maybe the Thais are generally healthier when it comes to cardiopulmonary and diabetes related issues (which seems to be the major contributor to the Wuhan Virus fatalities) than many Americans. I haven’t noticed any healthy ACTIVE athletes or politicians recently dying WITH virus complications. Regardless, you make more sense that Steve Adler. There’s another politician with a faulty compass.

  17. As I have mentioned on this site before, I believe an effective vaccine isn’t going to happen. We can hide in our basement while the economy collapses or we can travel. I agree w/ Gary…..there is still no convincing evidence that the transmission rate on aircraft (or anywhere else for that matter) is something to worry about. Wear a mask if you think it helps (or the local regime mandates it), and get on with your life. If you are an older guy like me, better get in shape. If you can’t or won’t….two choices hunker down and order in…or get out and take your chances, no medical degree required!

  18. @PforL Mike: I hope you aren’t making financial wagers on the vaccine question because there are already at least 2 candidates that have demonstrated at least neutralizing antibody responses and 1 of those has also demonstrated a T-cell response in humans. The latter of those has also demonstrated immunity in resus monkeys.

    Obviously the length of immunity is still a question, but even 6 months would go a very long way toward protection and “herd immunity.”

  19. You need to investigate before advising: ” The advisability of medical evacuation insurance coverage may be greater and certainly more top of mind.” Many, if not all, of these companies will not evacuate a subscriber for COVID-19 related problems.

  20. Thank you for an excellent post gleff. I am amazed at the paucity of accurate information by some who have written responses.
    And I appreciate the thoughtfulness of others who have written, such as Walter who says “a vaccine alone might not make travel normal; but it is going to most probably be part of whatever the new normal is. Even if there are few regional vaccines of some limited effectiveness and acceptance, it may be necessary to partake if you want to visit this or that part of the world.” Also, I agree with Autolycus who says “I understand your pessimism, but it’s worth noting that both major SARS viruses and the very similar MERS virus mutate far less frequently than the corona viruses that cause many “common cold” infections. Also, not all common cold viruses are coronaviruses. There’s some reason to worry that immunity from a SARS-CoV2 vaccine will not be long-lasting like vaccines for polio or even tetanus, but if it’s good for at least 6 months to a year and that can be “renewed” with a booster, we can eliminate or reduce severity of a huge portion of infections. Conceptually, there is nothing that makes it impossible to create a vaccine for specific viruses that cause the common cold. There’s just not enough benefit to it to justify the cost, especially when there are so many virus types and strains.”
    Let’s look at a few facts:
    1. This is a corona virus, a single-strand RNA virus. These viruses are more likely to mutate that DNA viruses. But there are some portions that the virus needs to keep stable, such as the spike protein that binds to the human ACE2 receptor to allow it to invade the cell. So targeting this spike protein (as an antigen) makes a lot of sense. And, indeed, that is what is being done by many.
    2. There is nothing “magical” about this virus. It appears to be comparably transmissible to measles (which is the most contagious virus that we know of). But far less lethal than many other viruses, such as Marburg (fatality rate approaches 100%). The news media seems to be focused on scaring the living daylights out of the public (congratulations, you did it !!).
    3. It is completely normal for both B-cells and antibody concentrations to decrease over time (over a short time usually). For example, we likely all received either an injectable or oral polio vaccine when we were very young. Today, if I drew blood from each of the readers on this site, I would likely be unable to measure serum titers of antibody to poliomyelitis virus. And yet, we are all likely highly immune !! WHAT??? How can this be? Well, after an event (e.g., an infection, a dose of a vaccine), our bodies produce large quantities of plasma cells (most quickly), B-cells, and T-cells (certain types of T-cells) against the virus or antigen or whatever. But we don’t want to run around for the rest of our lives in a “hypervigilant state”, filled with billions and billions of cells and antibodies. So, our body allows most of these cells to die (a normal biological process called apoptosis), and antibodies to be cleared by the reticuloendothelial system. BUT (and here is the BIG exception), a few of the plasma cells and B-lymphocytes survive, and go and live as “Granma Moses cells” in our bone marrow or lymphatic tissue, and wait for a new exposure so that they can rapidly respond. Bottom line: falling levels of cells and antibodies is normal. The question that we don’t know YET is whether immunity persists in a small number of long-lived cells.
    We will SOON have additional therapies, such as antibodies to the virus. Those should be available first. And I predict that we will have at least one or two vaccines before year-end.
    Travel will be changed forever. But “change” doesn’t equal “lost”. We may just have to change some of our travel patterns and get on with our lives.
    Having seen a number of patients who are infected with the SARS-CoV-2 virus (have Covid-19), most are surviving. And likely travel will survive, too.

  21. Wow! you need to get back to hiding behind your sofa with a mask and shield on, sheesh, like lets live in fear of everything while we are at it .,you bought this plandemic hook line and sinker ,probably fight your way to the front of the microchip line when they mandate it.

  22. If vaccine will open up travel why can’t travel be opened up today ? There are a lot of people having antibodies already that doesn’t need a vaccine to get antibodies.

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