Editor’s Note: Khalid Usman is a partner with Oliver Wyman’s transportation and services practice and a former airline executive. Dr. Bruce Hamory, Oliver Wyman’s chief medical officer, was chief medical officer for Geisinger Health System and a professor of medicine at Penn State, where he specialized in infectious diseases and epidemiology. Andrew Buchanan is a vice president for Oliver Wyman’s transportation and services practice and a former airline executive. The opinions expressed in this commentary are their own.

Parts of the world may be facing new restrictions amid rising Covid-19 case numbers and the emergence of the Omicron variant, but the pent-up demand for air travel in the United States is unlikely to subside.

Despite the newest variant’s detection in at least 32 states so far, airlines and airports in the US are likely to see lots of full planes and crowds as we approach Christmas and the end of 2021.

Were it not for the Omicron variant, domestic air traffic this holiday season would probably have approached 2019 volumes for the first time since the start of the pandemic. But even after the variant’s emergence in the US, domestic airline capacity — a measure of seats available and the distance they’ll fly — stands at 94% for the Christmas season, the highest level attained in 2021. That’s based on our analysis of airline schedule data.

Some of the increased demand reflects recent availability of Covid vaccines for children ages 5 through 11, which makes it easier for families to travel, as well as the wider dissemination of booster shots for adults. Additionally, last month’s lifting of US travel restrictions on vaccinated visitors from 33 nations, including many European countries, provided another boost, according to data from the International Air Transport Association.

When no restrictions apply, the various data confirm travelers are willing to take trips for leisure, despite rising case counts and hospitalizations.

Take the situation after Covid’s Delta variant began to take off in the US. Even as new Covid cases surged in late August and the first half of September, the TSA traffic percentage (76.3%) that month — representing a year-over-year comparison with 2019 — was only marginally lower than the July percentage (80%) when there weren’t many cases. By our calculation, Covid only reduced the volume by around 3%.

Even with some nations closing their borders again because of the Omicron variant, and the US implementing tighter testing requirements for those entering the country, it’s likely that December holiday air travel will mirror the high numbers we saw at Thanksgiving. This year, slightly more than two million travelers on average passed daily through Transportation Security Administration checkpoints at the nation’s airports during the 10 busy days leading up to and following the holiday. That’s about 89% of 2019’s volumes.

The question the travel industry needs to be asking is how to live with an endemic infection that may have another several years — and who knows how many variants — to go before universal vaccination puts it to rest. Travel restrictions don’t tend to stop the spread, unless they are as extensive as China’s, where few foreigners can visit.

To keep passengers safe and help stop the spread, testing is the more reasonable option, but it too can curb demand. A few destinations in the Caribbean and Mexico have tried to mitigate the negative impact of testing by working closely with hotels and test providers to make travel-related testing less stressful for tourists. These programs include the ability to use in-home tests and the sale of health care packages that cover all testing needed during a visit.

No doubt, vaccination, masking, testing and spending time in places with good air flow are the best defenses against Covid, according to medical expert advice. And effective travel policy should rely on a combination of those to contain future outbreaks.

Omicron and Delta have shown us that the real key to keeping Covid and its variants at bay is to keep vigilant and resist the temptation to relax the rules just because the virus temporarily slips from the headlines. Covid isn’t going anywhere for a while, but we can put smart protections in place so that travelers will be able to.