Mask mandates were just about the only thing that made parents of kids under 5 — who are still ineligible for the COVID vaccine — feel safe enough to fly. But on April 18, the public transportation and airplane mask mandate was struck down. Since then, all major U.S. airlines have announced that they will no longer require masks at this point in the COVID-19 pandemic. Given this, should you cancel your travel plans and opt for a vacation closer to home?
“Every family is going to need to make their own assessment of potential risks and their comfort level with those risks,” says Sallie Permar, M.D., Ph.D., Chair of the Department of Pediatrics at Weill Cornell Medicine and a pediatric infectious disease specialist. This is what you need to consider when making your decision.
What is the risk of COVID transmission on planes?
Air circulation and filtration are generally very good on planes. In varying proportions, air on planes is either recycled through HEPA filters, which filter out nearly 100% of the coronavirus-sized particles that pass through them, or is pumped in from outside the plane. Air is completely replaced every few minutes (35 air changes per hour on a Boeing 777 compared to 20 per hour in an operating room).
Yet COVID transmission on planes undoubtedly occurs. One 2021 study used genetic testing to identify at least four instances of likely in-flight transmission from a pair of infected travelers that occurred despite pre-departure testing, use of masks by many passengers, and low plane occupancy (only 86 passengers on a plane that holds 340). A 2021 review of 18 published studies found a secondary attack rate between 0% and 8.2% — this is the percentage of people who tested positive after being on a plane with the original infected person out of everyone the researchers were able to trace. However, the researchers concluded that “published data do not permit any conclusive assessment of likelihood and extent” of transmission during air travel.
“Wherever people are together, there’s transmission,” says Annelies Wilder-Smith, M.D., Ph.D., a professor of Emerging Infectious Diseases at the London School of Hygiene and Tropical Medicine. “There are lots of examples where there was transmission on airplanes, but I think you have to put it in perspective compared to other modes of transportation.” Compared to cruise ships, for example, airplanes are much lower risk, she says.
Although the risk of catching COVID on a plane is comparatively low, a mask requirement would still be the safest option. The Harvard T.H. Chan School of Public Health report on COVID transmission on planes, often cited as support that air travel is low-risk, noted that, “face mask requirements are perhaps the most essential layer of a comprehensive set of measures to reduce transmission of COVID-19 throughout air travel.”
With masks or without, the part of air travel you really need to worry about is before you take to the sky. “The time when you are getting on and off the plane poses the highest risk,” says Wilder-Smith. Although planes’ ventilation systems are quite good, they may not actually be running until the plane takes off, she says. The airport itself also doesn’t have as good ventilation as a plane, so masking and distancing in the airport (as in any other indoor space) is helpful. If your child needs to eat or drink, such as on a long flight, doing so while in the air is the safest choice.
How likely is your child to get COVID or to have a severe outcome?
In the U.S., COVID is by no means uncommon in children: Kids have accounted for about 19% of all cases. Thankfully, severe outcomes remain relatively rare.
“Generally, children are less at risk for severe disease compared to older individuals,” Permar says. “However, we did see in these Omicron variant surges that we did have increased hospitalizations of young children. But still, overall there is a relatively low risk of that, less than 1%. That is something that parents should be aware of as they’re making decisions about their comfort level with risk during travel.”
The risk of contracting COVID — or of developing severe disease — is not the same for all children. Some factors may reduce your child’s risk. For example, Permar says, “we know that recent infection does provide some protection against a new infection.” In this case, “recent” is within the past 90 days, although Permar notes that this is only a general guide, especially since the virus is evolving fairly rapidly.
On one hand, children who are too young to mask may be at higher risk, since wearing a well-fitting mask, particularly a high-quality mask like an N95, provides some protection. On the other hand, children under six months may have some added protection if their mothers were vaccinated. “We know that if you are vaccinated, during pregnancy or before pregnancy, then you do pass those antibodies on to your babies, and those last at least through the first six months,” Permar says. “Research is still going on as to exactly how much protection that provides. But studies on maternal immunization have shown that it does help prevent hospitalizations in infants.”
Children under 18 in general may be more likely to experience severe outcomes if they have medical conditions such as diabetes or heart abnormalities. If your child has any type of chronic condition, Permar suggests discussing COVID risks with your pediatrician before hopping on a plane.
Like adults, children can end up with long COVID, even if initial symptoms are mild. However, how frequently this happens — and how severe symptoms generally are — is still a matter of debate. Reported persistence of at least one symptom varies widely — from 1.8% to 66% of children who get COVID. However, it’s difficult to compare data as different studies may measure different symptoms and have different definitions for what duration of symptoms counts as long COVID. Furthermore, many symptoms of long COVID — headache, fatigue, difficulty sleeping or concentrating — are also reported in children who did not have COVID. And in some cases, they could be related to the stress of living through a pandemic, rather that the virus itself.
If you do decide to travel, how can you reduce your child’s COVID risk?
As in any crowded indoor space, masking is an important part of risk reduction, even if the people around you aren’t wearing a mask. The type of mask you wear is important too, Permar says.
“If you’re taking a child on a plane, and you want to have the most protection for that child, it would be using a well-fitting KN95 or N95. Some of those are now available in child sizes,” she says. Surgical masks provide the second-best protection, followed by cloth masks, she adds. You can layer a cloth and surgical mask for added benefit.
Wilder-Smith says she believes mask-wearing should still be encouraged but that the removal of mask mandates on planes reflects general relaxing of restrictions across the U.S. and Europe. However, she says we may need to re-evaluate the safety of all activities, including air travel, in the fall and winter when there will likely be more viral circulation.