Does Travel Spread Covid?

A few days ago, I received a comment on my post about the Covid-19 Omicron variant that said people shouldn’t travel because travel spreads Covid. Yikes! Spreading Covid is bad, very bad.

Having a condition and age that makes me susceptible more than the average person to dying or being hospitalized if infected, I try very hard to avoid getting infected. If I’m not infected with Covid, I can’t spread it. I realize there are no guarantees about not getting it.

Those who have no degree in infectious diseases nor any professional training or experience in that field listen to the experts and try to understand and sort out what they are saying. The experts do their best but are hampered by science’s incomplete understanding of the SARS-CoV-2 virus and the disease it causes, Covid-19.

One thing that all of the experts agree on is people become infected with the virus and spread it through contact with other people. SARS-CoV-2 is emitted when an infected person talks, coughs, sneezes, or sings, mainly in droplets that can be propelled a short distance, and sometimes in smaller aerosol particles that can remain suspended and travel further. Another person can be infected if these particles reach their mouth or nose directly or via hands. It doesn’t matter if people are at home, one mile from home, 10 miles from home, 100 miles from home or 1,000 miles from home. What matters for spreading the virus is the amount of contact with people and the extent to which the risks of transmission are being mitigated during those contacts.

When it comes to analyzing travel’s affect on Covid spread there are millions of variables at play. To keep things simple, I think about it from this general standpoint: Do people have more contact with others when they travel than they do when they don’t travel, and are people mitigating their risks when they travel less than when they don’t travel? The answer: It depends.

Contact With People

Before I retired I definitely had more contact with people when I was not traveling. The vast majority of those contacts were indoors and related to work. At this point in life, I may have slightly more person-to-person contact when I travel. On the other hand, when traveling a larger proportion of my personal interactions are often outdoors compared to when I’m at home.

Last year in the United States, the Thanksgiving and Christmas holidays saw spikes in travel and spikes in Covid cases.  One might surmise that travel (the act of going from one place to another) was the cause of the increase in transmission.  In reality, I believe it was what people did when they got to their destinations — gathering indoors in large groups with insufficient risk mitigation — not traveling that caused the increase in infections.  Many large indoor holiday gatherings that contribute to spread are entirely local affairs that involve no travel.   

Risk Mitigation

Getting vaccinated and boosted with a good Covid-19 vaccine reduces, but doesn’t eliminate, the chance of contracting and spreading the virus. Vaccines also reduce the likelihood of becoming ill or dying if someone gets infected. Being vaccinated is a requirement for a lot of international travel. Unfortunately, there are no vaccine requirements for domestic air travel in the U.S..

Short of being vaccinated, wearing masks, social distancing and washing or sanitizing hands offer the best protection. Fever is one of the symptoms of Covid-19. In Thailand, many hotels, restaurants and malls also use temperature checks. The accuracy of some of these devices may be questionable. Still, they are better than having no temperature checks.

I’m privileged to say I’ve been vaccinated and boosted with the Pfizer-BioNTech vaccine. During my travel experiences, I’ve worn a mask, washed hands and socially distanced myself from others when possible more than I do when not traveling. That is partly due to heightened awareness on my part but mostly due to insistence on things like mask wearing, social distancing, and temperature checks, and the prevalence of hand sanitizer stations in the tourist dependent places I’ve visited. Where I live, many places don’t require masks indoors or in crowds outside and many that say they do don’t enforce the rule.

I recently visited Greece and Thailand. In Greece, the only indoor tourist attraction I visited was the Delphi Archeological Museum. Don’t even think about entering that facility without being fully vaccinated and having the certificate to prove it and wearing a mask at all times. In Bangkok everyone wears a mask even outdoors. Bars and nightclubs were closed. Restaurants could sell alcohol only until 21:00 (9 pm). Temperature checks were everywhere.

The only way to guarantee that travelers are not infected is to force all of them to quarantine for 10 to 14 days at their destination. Very few would travel domestically or internationally under those circumstances.

Air Travel

I make no claims about trains or other forms of travel, but air travel is very safe. All Boeing and Airbus commercial airliners and many regional jets are equipped with HEPA air filters comparable to those found in hospital operating rooms. These filters remove virtually all viruses and bacteria. Even the most difficult particles in the range of 0.1 to 0.3 micron are filtered out with an efficiency of 99.995%. Airplane ventilation systems recirculate the volume of air in the cabin every two to three minutes and mix recirculated filtered air with fresh are from outside the plane. Cabin air enters through vents near the ceiling and exits through through vents near the floor. The downward flow of air minimizes mixing of air between rows.

I recommend N95 or KN95 masks for flying. They have the best filters of any face masks. Both filter out at least 95% of particles such as viruses and bacteria. The N95 mask may be a tad easier to breathe through. I prefer the KN95 because many of them have straps that fit over the ears rather than having to put the straps behind the head like the N95 masks. Straps that go behind the head make putting on and taking off the mask a lot harder and may mess up your hair if that’s important.

Since the start of the pandemic, all airlines have instituted enhanced cleaning procedures. Some use enhanced cleaning between every flight. Others employ the new procedures daily. Masks are required for all passengers except when eating or drinking. Many airlines have eliminated most service for passengers in the economy cabin and cutback or modified service in premium cabins.

The safest I’ve felt in public in a long time was on a flight from Tokyo to Bangkok on November 2, 2021. In addition to the HEPA air filters and enhanced cleaning, all passengers wore masks 100% of the time when not eating or drinking;100% of the passengers had received a negative result on a RT-PCR test in the last 72 hours; 100% of the passengers would be retested in a few hours on arrival in Bangkok and any positive results would lead to contact tracing based on the seat assignments on the plane; 100% of the passengers completed a health questionnaire designed to identify Covid symptoms; and 100% of the passengers were fully vaccinated with approved vaccines. No other public environment, not even a hospital, offers that mush protection against Covid spread.

The definition of fully vaccinated needs to change, and I’ve said so before. When the experts announced that protection of the current vaccines wanes overtime and recommended booster shots, it seemed obvious. Effective vaccine protection has an expiration date.

That is not to say Covid cannot be transmitted on a flight. Whenever people are together there is a chance of Covid transmission. There have been documented cases of spread on commercial flights. For example, see here and here. However, with the mitigating factors on airplanes, the risk seems low as the American Medical Association article referenced above concluded. If Covid transmission was occurring with any regularity on planes, wouldn’t all of the flight attendants have it?

The Thailand Experiment

The entire world is going through a Covid-19 experiment. Lessons learned will inform responses to future pandemics. Thailand closed its borders to travelers for months allowing only those willing to quarantine in a hotel for as long as 14 days to enter. On November 1, 2021, Thailand opened to vaccinated travelers without quarantine as long as they tested negative on pre and post arrival RT-PCR tests. Will more visitors lead to more infections? That remains to be seen. So far infections are dropping while the number of visitors is increasing.

What Will It Take To Return To Normal?

Vaccines were touted as the way to the promised land of carefree pre-Covid life. It now seems impossible that many countries, including the United States, will ever reach herd immunity through vaccinations. Covid mutations continue to emerge that to various degrees evade the protection afforded by prior infection and existing vaccines. To this layman, it seems that life will only return to a form of pre-Covid normalcy when therapeutics are developed that prevent the vast majority of SARS-CoV-2 infections from becoming serious cases of Covid-19.

Final Thoughts

Does travel spread Covid? The way I look at it, no. Travel is no more of a spreader of Covid than what people do when they are not traveling. It is what people do, not where they do it, that spreads SARS-CoV-2 and its pesky mutations. Air travel is safe if people follow the procedures and practices designed to mitigate risk of transmission. The same can be said about activities at the travel destination.

Should we travel? Each person gets to decide if he or she is comfortable traveling and the method of travel they prefer.

Please add your thoughts about this subject in the comments. Thanks for your time and interest, and happy traveling, or not.😊