Was The World Too Slow To Embrace Travel Restrictions As A Way To Stop Covid-19?

The New York Times covers the complicated question of whether travel restrictions are good policy in a pandemic. The World Health Organization was strongly against them. Many countries adopted them. They seem to have helped in some places and not others.

Before the pandemic, a few studies had demonstrated that travel restrictions delayed, but did not stop, the spread of SARS, pandemic flu and Ebola. Most, however, were based on mathematical models. No one had collected real-world data. The effect of travel restrictions on the spread of the latest coronavirus is still not understood.

“Anyone who is truthful is going to tell you it’s a big fat ‘We don’t know,’” said Prof. Keiji Fukuda, a former senior World Health Organization official who teaches at the University of Hong Kong.

The U.S. ban on travel from China didn’t work. It turns out it came in time, even though the virus was already inside the country, because those cases petered out. But it was still ineffective. People flew to Vancouver and then entered the U.S. The CDC failed its screening and enforcement role.

The U.S. ban on travel from Europe came too late. It’s the European virus strain that entered New York and largely spread throughout the country. The virus that spread was already here when the ban was put into place.

We never had bans on travel from Iran, Qatar, and any number of other virus hot spots.

The virus has been contained (or at least was contained for awhile) mostly in small, remote countries. The question of why we haven’t seen tremendous spread in places like Thailand, Laos, and Cambodia is a real mystery (their ‘lockdowns’ and public health responses were far from equal, and 90% of Thai cases have been asymptomatic).

Once a virus is in a country and spreading within the community, travel bans don’t offer much protection. The U.S. maintains several bans, including China and Europe, but it’s not clear to what end. Incremental cases brought into the country don’t materially change the direction of spread here.

Keeping a virus out is very hard, ‘viruses are gonna virus’, if you ban passenger travel but still have cargo and the virus spreads via asymptomatic or presymptomatic individuals then cargo crew could bring it in. They could interact with customs or shipping authorities. If a country’s citizens are allowed to return even with quarantine, they could bring the virus in and how perfect is the quarantine? In Melbourne, Australia a quarantined passenger had sex with a guard who contracted the virus and spread it (The Australian state of Victoria practically went ‘full Wuhan’ in its response).

We’ve learned a tremendous amount about this virus in 8 months. The biomedical response has been incredible. But at the beginning we thought fomites and respiratory droplets were the main pathways of spread and aerosols were a non-issue, and that asymptomatic spread was a non-issue as well. Without the knowledge we have today it’s hard to go back and know the right responses then – and whether we could carry out those responses effectively.

The Northeast got the ‘first wave’ of the virus in the U.S. Florida, Texas, Arizona and a few other states were hit with a second wave. Some criticized states for opening up too early, in some sense they may have locked down too early – because there’s only so much lockdown people would stand for and it would have been better to lock down when spread was happening. But there wasn’t much testing at the beginning of the pandemic either and no one knew whether there was spread when lockdowns began.

The issue isn’t just foreign travel either by the way, the virus entered the U.S. but then spread from the Northeast. Perhaps the Europe ban came too late, but domestic travel bans would have worked.

What does it mean to work, though? Would we have been able to contain the virus? Or would we only have been able to delay spread? Delay of course mattered to prepare hospitals in case they faced the sort of overload that hit New York. It helped to give time to build stocks of PPE. And getting the virus later has been better than getting it at the beginning.

Back in February I mused that I might prefer to get it early, on the theory that I’d receive better treatment before hospitals becoming overcrowded. In hindsight I’d certainly have preferred a mild case, followed by perhaps a year of robust immune response (if not long-lasting antibodies) than limiting contacts for so long.

However what waiting has brought is much better patient outcomes – from treatment protocols to antivirals and steroids, it looks like beta interferon will help some patients, and soon we’ll have (an insufficient supply of) monoclonal antibodies as well. It’s better to have a bad Covid case now than back in March or April.

So would travel bans have helped? Could they have been executed effectively? Would they have been worthwhile? My own guess is they can be helpful in theory but they’re really hard to pull off – that at most, for most countries, they can delay spread. And in the case of Covid-19 delay is helpful but that’s not always the case (and it wasn’t something we could have known during the first couple months of the year, because we didn’t know what we didn’t know).

Ultimately the U.S. probably lacks the ability to lock down travel the way some island nations have.

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. I sincerely hope that the response to Covid-19 will be studied extensively without bias or interference from political or media institutions. In many ways it is the greatest social, psychological, epidemiological, governmental experiment in the history of mankind with more data points than anyone could process in a lifetime.

    This is unlikely to be the last time we confront a pandemic. Wouldn’t it be great to have real plan in place when the inevitable happens again? Are lockdowns effective? Maybe. Travel bans? Maybe. Cloth masks? Maybe. Yeah, that’s like saying Jesus was just a carpenter. But you gotta be open to that possibility.

    Adhering to the scientific method takes lots of time, data, and review. And a willingness to be proven wrong. To begin with a conclusion defeats the purpose. Do we as a society have the ability to admit we’re wrong regardless of the outcome of actual science and accept it as fact? Knowing that many still believe the world is flat.

  2. Correction- Do we as a society have ability to admit we’re wrong when confronted by actual science and accept it as fact.

  3. That last point is key. Small countries with limited access points (New Zealand, Singapore) have been the only place where travel restrictions have made a meaningful difference. Places such as the EU and USA have so many people going in and out from so many points that by the time you even had a hint that there was a problem, it was far too late for restrictions to help because the virus was already widely spreading.

  4. Same with masking. There was some limited, but not statistically significant studies from Asia that showed that wearing masks limited the spread in previous viruses so they weren’t prominently pushed. When people originally started wearing masks in United States I argued it was good, not because it’d likely prevent people getting it (as people wearing them intended), but that it’d stop those unknowingly carrying from spreading (and that really we all should) and was swiftly dismissed because ‘wearing a mask made you more likely to touch your face’ and that the officials were saying masks were not needed.

  5. Australia’s travel ban was initially just China, then expanded to cover the whole planet. Even citizens are restricted from entering the country (there is a waiting list of over 25,000 people) because the government insists on 14 day hotel quarantine for all travellers, and there just aren’t enough hotel rooms and security guards to implement it. They have just started to allow New Zealanders to visit us (not reciprocated).

    So we’ve avoided high numbers of cases and deaths (except for Victoria) but at the cost of nobody being allowed to enter or leave. It’s nice to be able to go to bars, restaurants etc. without worrying that you’ll inadvertently kill grandma next time you see her but it’s starting to get annoying that there’s no end in sight to the total ban on foreign travel. Though with greatly diminished cabin service on most airlines, flying isn’t that appealing yet.

  6. You can delay the spread of a virus but it’s very hard to stop it. With a place like the EU or US the boarders are very porous. Thousands enter illegally on a daily basis so even if you shut down every flight, car and ship the virus will continue to enter at a slower rate. You might be able to flatten the curve but it just makes the time line longer to work through it. I see people argue that we will have to stop travel or wear masks until there is a vaccine. Most have no idea that it can take 10 or more years for an effective vaccine. We have tried to fast track that but the FDA has now shut that down to normally slow levels.

  7. It’s not as if we didn’t have forewarning: SARS, Bird Flu, MERS and Swine Flu should have prompted a much stronger, faster response ( even though it’s acknowledged that some of the current vaccine progress has been fast-tracked as a consequence of those earlier threats).
    Unfortunately we tend to believe ‘it’s not gonna happen’ , or if it does, ‘not to me/us’, ie ‘the fire on the other side of the river’, as the Japanese saying goes.
    The WHO must take a lot of the blame: ‘no evidence that it’s airborne’, ‘no need for travel restrictions’, ‘masks aren’t helpful’, ‘no evidence of spread outside China’, ‘human to human transmission is not easy’. Clueless C***s.

  8. Gary – As a doctor, I can tell you it is obviously better to get Covid now than it was 6 months ago; we are more adept & knowledgeable about treatment. Mt. Sinai (Miami Beach) mortality & hospital length of stays declined markedly, some say by 50%. And more treatments will become available over the next few months.

  9. The answer is resoundingly yes. President Trump shut down travel by non citizens from China on January 31, 2020. Many people on travel blogs and Joe Biden himself criticized the move as excessive, xenophobic, and anti democratic. The ban was later extended to other Asian countries and finally to non citizens/residents from Europe in March. Even at this late point in March, most travel bloggers were criticizing the move. Travel bans were an effective way contain the virus but political pressure caused them to be issued to slow and they didn’t prevent citizens from returning before an accurate testing regiment was set up.

    It’s much easier to ban travel from certain countries or all countries than it is to lock down a country within. The former is certainly a fair option. The latter is an infringement on fundamental freedoms; the right of friends and family to visit each other on private property should not be up for debate nor should the ability for people to voluntarily and consensually engage in commerce. It’s not prudent to shut down a country over a virus in which 95% have no or mild symptoms, 99.87% of people don’t die, and vulnerable groups can isolate at home or in their nursing homes (if state governments like NY were competent) like they should during flu season. We missed our chance with travel bans from other countries. I blame those that denounced them in January, February, and March.

  10. @Terry – absolutely, something I have been writing for many months. IFR dropping, we know so much more than we did and better treatments on the way.

  11. Science is not exact. You propose a theory, test it, and if it fails, you go and study it further until the theory fits the circumstances of the event.
    I’m sure Trump did the best under the circumstances and I don’t suppose Biden could have done any better in handling the situation as superbly as our Commander in Chief did.

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