Is it safe to fly? Two scientists tell you what you need to know

Nov 18, 2020 / +

This post is part of TED’s “How to Be a Better Human” series, each of which contains a piece of helpful advice from people in the TED community; browse through all the posts here.

Editor’s note: An earlier version of this piece was published in June, but the coauthors have updated it to address the current situation and latest science. In addition, the US Centers for Disease Control just issued updated guidance for celebrating Thanksgiving, and it is recommending that people not travel for the holiday. 

Summer has come and gone, and the holidays are now upon us. While so many of us made choices to stay close to home this summer, some of us are anxious to see our loved ones after so much time apart.

As mothers and as an exposure scientist and infectious disease epidemiologist, we are thinking about this issue of travel and the safety of flying because the rate of COVID-19 transmission is continuing to increase across the US and much of the world. Since our original piece was published, there have been a few instances of outbreaks resulting from plane travel. Here is our current take.

Why the concern about flying? 

The primary concern with flying — or traveling by bus or train — is sitting within six feet of an infected person. Remember: Even asymptomatic and pre-symptomatic people people can transmit. Your risk of infection directly corresponds to your dose of exposure, which is determined by your duration of time exposed and the amount of virus-contaminated droplets in the air.

The problem with travel is it brings together people from many places and risk levels and puts them into a common space together where they share the same air, which is of particular concern when they’re within six feet of each other.

A secondary concern is contact with contaminated surfaces. When an infected person contaminates a shared armrest, airport restroom handle, seat tray or other item, the virus can survive for hours, although it does degrade over time. If you touch that surface and then touch your mouth or nose, you put yourself at risk of infection.

Before you book, think 

While there is no way to make air travel 100 percent safe, there are ways to make it safer. It’s important to think through the particulars for each trip.

One approach to your decision making is to use what occupational health experts call the hierarchy of controls. This approach does two things: It focuses on strategies to control exposures close to the source, and it minimizes how much you have to rely on individual human behavior to control exposure. It’s important to remember you may be infectious and everyone around you may also be infectious, since you are most infectious before your symptoms even appear. Remember: During air travel, it isn’t just your behavior that is important but the behavior of those around you as well.

The best way to control exposure is to eliminate the hazard. Since we can’t eliminate the new coronavirus, ask yourself if you can eliminate the trip. Think extra hard about traveling if you are older or have preexisting conditions or if you are going to visit someone in those categories.

Be sure and check the local COVID-19 rates in the region you are considering visiting, and minimize your travel to regions of high transmission. However, keep in mind on a plane that you’ll be exposed to people who come from anywhere and everywhere.

With the promising news about vaccine development for 2021, you might want to consider skipping holiday travel this year. With cases on the rise in much of the world, we all need to hunker down and do our part to reduce transmission as much as possible. Travel poses a risk not just of infection en route, but you could be exposed in one place and then bring the virus to your loved ones and your community where the rate of infection might be lower. (Of course, holiday travel associated with family and social gatherings — it is important to note that small social gatherings are thought to be one of the primary drivers of infection, so please follow guidelines if you are planning to attend or host one.)

If you decide that you are going to make the trip, think about ways to reduce the risk of exposure. Is it possible for you to drive? By now, both of us have successfully taken road trips with our children while practicing  precautionary measures like physical distancing, good hand hygiene, packing our own food, wearing masks, and following the safety guidance for hotels. Driving also allows you to have more control over your exposures rather than being buckled into a seat on an airplane.

You’ve decided to fly. Now what? 

Strategies to keep you safer while flying have increased, but these vary quite a bit by region, airport and airline and over time. Should you choose to fly, check out the different airlines’ policies for seating, boarding and cleaning. Some are minimizing capacity and spacing passengers by not using middle seats and having empty rows; however, most are loosening these restrictions or in the process of doing so.

Make sure that you are updated on when their policies could change. Some airlines are strict about requiring passengers to wear face masks, while others are less likely to enforce their use. Others are boarding passengers from the back of the plane. Nearly all airlines have now instated additional cleaning precautions and tested their ventilation efficiency, and some are screening people for fever prior to boarding. Federal and state guidance is constantly changing, so if you’re traveling out of state or out of the country, look up the most recent guidance, advice, policies, travel restrictions and quarantine restrictions from government agencies, airlines and airports.

Check out your airline to see whether it has engineering controls that are designed or put into practice to isolate hazards. These include ventilation systems, on-board barriers and electrostatic disinfectant sprays on flights. When the ventilation system on planes is operating, planes have a very high ratio of outside fresh air to recirculated air — about 10 times higher than most commercial buildings. Plus, most planes’ ventilation systems have HEPA filters. These are at least 99.9 percent effective at removing particles that are 0.3 microns in diameter and more efficient at removing both smaller and larger particles. However, not all planes or airlines have this equipment.

But keep in mind that it isn’t just what happens on the plane. One of us (Kacey) recently went to an airport, and what she saw did not resemble the videos of empty airports that have been shared. There was the good: She noted new UV disinfecting handrails on escalators, sanitation stations and individuals handing out face coverings. But there was also the bad: There were a lot of people (think close to pre-pandemic levels), and there was minimal distancing at security and check-in. And there was the ugly: Although she did not personally witness it, friends who’ve traveled have reported seeing individuals who refused to wear a mask despite requests from flight attendants.

In our original post, we suggested that people may want to take multiple shorter flights instead of longer duration flights. However, we’ve since realized that any benefit would most likely be countered by long wait times in airports. Of more importance is minimizing your travel duration and your number of contacts. So, try to take direct flights — even if you may need to rent a car for a one- to two-hour drive — to reduce the number of potentially infected people that you encounter.

When you book your flight, select a window seat if possible. If you consider the six-foot radius circle around you, having a wall on one side would directly reduce in half the number of people you are exposed to during the flight, not to mention all the people going up and down the aisle.

How to be safe from shuttle to seat

To minimize risk from going through security to boarding:

Bring hand wipes to disinfect your seat belt and your personal belongings, like your passport. If you cannot find hand wipes, bring a small washcloth soaked in a bleach solution in a ziplock bag. This will probably freak out airport security less than carrying a personal spray bottle, and viruses are not likely to grow on a cloth with a bleach solution. But remember: More bleach is not better and it can be unsafe. You need only one tablespoon in four cups of water to make an effective solution.

Bring plastic ziplock bags for personal items that others may handle, such as your ID. Bring extra bags so you can put these objects in a new bag after you have the chance to disinfect them.

Wash your hands or use hand sanitizer as often as you can and always after you touch surfaces. While soap and water are most effective, hand sanitizer is helpful after you wash to get any parts you may have missed.

Wait in the airport area as far away from others as possible. Wait until later to board the plane so you can minimize your wait time and your time spent in the jetway where ventilation is typically very poor.

Once you get to your window seat, stay put. Turn your face towards the window, and turn on your air vent fully. This may shower you with clean air and disperse any viral particles.

Wear a mask. New evidence demonstrates that even wearing a cloth face mask protects not only others but provides you with more protection than wearing nothing at all. If you are using a cloth face mask, opt for one that meets the latest recommendations — triple layers, with two layers of cotton and one filter-type layer made of something like polypropylene. Make sure that it fits you well, is comfortable, and has minimal air gaps. Avoid touching, adjusting or removing it during your travel. Respirators are 95 percent effective at filtering out the virus if used properly. KN95s are more comfortable than N95 respirators, which should be fit-tested before you use them.  But respirators are in short supply again for healthcare workers, so you should opt for a high-quality cloth covering unless you are in a high-risk category or you already have a respirator.

Do not wear masks with a valve, and avoid individuals who are wearing masks with a valve. While these masks are cooler and make it easier for people to breathe, the valves work like a chimney for your exhalations and defeat the purpose of wearing a mask to trap contaminated droplets and effectively protect others.

Do not eat on the plane, and minimize your drinking. It is difficult to maintain six feet of distance while eating without a mask on the plane. It is better to eat in the airport or, even better, before or after your trip.

Avoid using the lavatory on the plane as this increases the number of people you will be within six feet of. It is better for you to use the restroom in the airport. If you do need to use the restroom on the plane, wait until there is no line, go to the closest one, minimize the surfaces you touch, and wash and sanitize your hands well. Do not remove your face covering.

If there is someone seated near you that is refusing to wear a mask or eating without a mask or talking loudly, don’t try to argue or reason with them. That can increase your face-to-face contact and your exposure due to increased respiration rates during those moments. Instead, ask the flight attendant if you can move to another seat.

We don’t recommend the use of gloves. They can lead to a false sense of security, they’ve been associated with reduced hand hygiene practices, and they may even lead to greater contamination of your belongings like your phone, tickets and ID.

If it makes you feel better, you can consider wearing a face shield in case someone directly coughs or sneezes on you. But these are not a substitute for a face covering or a respirator and they do not provide adequate protection for an airborne virus.

Get TSA pre-check if possible. It streamlines the process through security and minimizes your time in what is typically one of the most crowded areas of the airport.

If you are thinking about flying with children, there are special considerations to keep in mind. Getting a young child to adhere to wearing a mask and maintaining good hygiene behavior at home is hard enough; it may be impossible to do so when flying. According to the CDC, children under 2 should not wear a mask (it is not considered safe for them to do so).

Every day, we are all faced with decisions about our own personal comfort with risk. Ultimately, the cost-benefit of each decision is personal. Just this weekend, my (Kacey’s) 15-year-old daughter flew home on a short direct flight from her grandparents. It was a difficult choice, and it was made due to unforeseen issues. We chose an airline that has a reputation for following strict protocols, we changed her destination city to one that had direct flights, we ensured she had a KN95 mask and hand sanitizer, and we greatly minimized her time in the airport terminal by having her check in online, minimizing her luggage, and choosing a departure airport that was small and has easy access to the gates. Since she’s returned, she is minimizing her contact with our family — but please know that one traveler in a family increases everyone’s risk in the household.

If you decide to travel, arm yourself with specific knowledge about your airport and airline and maximize your use of protective measures that you have control over and that can reduce your risk. Overall, we are less worried about the transmission risk on the airplane — as long as all mitigation strategies are in place. While transmission can happen on a flight, it appears to be relatively rare.

To us, traveling now — while COVID-19 cases are poised to be the highest we’ve seen in the US — seems a bit like deciding to drive during a blizzard. Sure, you might have great snow tires and all-weather gear in your car, but why risk it if you don’t have to? Spring is on its way in the form of multiple promising vaccines; you just need to wait.

This article is republished from The Conversation under a Creative Commons license.

Watch this TED@BCG Talk about developing a COVID-19 vaccine: 

Watch Kacey Ernst‘s TEDxTucson Talk about mosquitoes here:

The Conversation