Three carbon monoxide deaths at a resort in the Bahamas called attention to the dangers of the odorless gas. In the U.S., where it often takes multiple poisonings for hotels to install alarms, a debate about detector policies has been intensifying.He was not the first guest to fall ill in Room 205. Just when Pawel Markowski thought that nothing could shake him more than nearly losing his life to a carbon monoxide leak at a hotel in Catoosa, Okla., his lawyer sent him the Fire Department’s report.“We have previously responded to this exact room number two other times in the last two weeks,” Denus Benton, Catoosa’s fire chief, wrote.“I don’t know what these people were waiting for — someone to die?” said Mr. Markowski, 44, whom a colleague discovered “unresponsive” on the floor of his hotel room on March 16, according to medical reports.Incidents like Mr. Markowski’s rarely break through beyond the local news. But when, in May, a carbon monoxide leak killed three Americans at the luxurious Sandals Emerald Bay resort in the Bahamas, it generated hundreds of news stories and sparked conversations about the invisible, odorless gas.After the tragedy, Sandals announced that it would install carbon monoxide detectors in all its hotel rooms in the Caribbean. In doing so, the company inadvertently called attention to the fact that most resorts and hotels, the world over, do not place detectors in guest rooms.The company’s action also fed into a simmering debate about how to prevent carbon monoxide poisonings in hotels in the United States. Though smoke alarms are normally required in American hotel rooms, no state and few hotel brands require in-room carbon monoxide detectors, which can be purchased for as little as $30. Some firefighters, doctors, activists and lawmakers have been pushing hotels to install them in every room. The lodging industry says that is unnecessary and too expensive.Those who want stricter detector requirements say the frequency of incidents necessitates change. In the past year, in addition to Mr. Markowski’s almost-fatal stay at a Hampton Inn & Suites outside Tulsa, carbon monoxide leaks at six other U.S. hotels killed two and injured at least 35 other guests and employees, including 10 children. In most of these cases, there was no working detector on site, according to interviews with fire officials, front desk staff and local news reports.In the past 20 years, at least 1,090 people have been injured by carbon monoxide leaks in U.S. hotels, with 32 people — including 7 children — dying, according to the Jenkins Foundation, a nonprofit that tracks carbon monoxide incidents at hotels. A study published in the journal Preventive Medicine Reports last year suggested that these figures could be many times higher given that so few incidents are publicly reported.The International Fire Code, which guides state and corporate policies but does not carry the force of law, was updated in 2012 to say that hotels should either place carbon monoxide monitors in common areas or in guest rooms. But when the code was updated in 2015, the lodging industry successfully lobbied to remove that requirement, according to interviews with key stakeholders.Many states and brands do require carbon monoxide detectors in rooms with fireplaces and near fuel-burning appliances, such as hot water heaters, in compliance with the current International Fire Code and other building codes. But in more than a dozen states, this only applies to newer hotels. At least six states do not require detectors in hotels at all.Both Airbnb and VRBO, which have dealt with at least 10 carbon monoxide deaths in Brazil and Mexico over the past four years, urge hosts to install detectors near every sleeping area, but do not require them. Airbnb offers hosts free detectors, but in a 2018 study, public health researchers found that only 58 percent of hosts said they had installed them.The Sandals Emerald Bay resort recently had a carbon monoxide leak that killed three people and injured a fourth. Dimitrios Kambouris/Getty Images for Sandals“How many people need to die and be permanently brain injured for it to matter to them as an industry?” asked Kris Hauschildt, whose parents died from carbon monoxide poisoning in a hotel room in Boone, N.C., in 2013. It was only seven weeks later, after an 11-year-old boy died in the same room, that investigators identified a leak from a pool heater.Ms. Hauschildt created the Jenkins Foundation, in part, to track the poisonings at hotels, something no entity was previously doing. In 2021, her findings helped compel the National Fire Protection Association, a nonprofit group that establishes safety codes that set some state policies, to require detectors in both new hotels and old hotels.The lodging industry generally takes the position that poisonings are too rare to rationalize costly changes, like requiring detectors in every one of the country’s 5 million or so guest rooms. Proper maintenance and installing detectors near devices capable of emitting carbon monoxide should prevent virtually all poisonings, lobbyists representing major hotel chains have argued.“Few hotel guest rooms have fireplaces or fuel-fired appliances capable of producing carbon monoxide, so warning devices such as CO alarms are a secondary defense,” a spokeswoman for the American Hotel & Lodging Association, which represents Hilton, Hyatt, Marriott and many other hotel companies, said in an email. “The proper maintenance of fuel-fired appliances precludes the likelihood of an inadvertent carbon monoxide exposure.”Kris Hauschildt at her home in Kalama. Wash. She holds a photograph of her parents, who died of carbon monoxide poisoning while staying in a hotel in North Carolina. Kristina Barker for The New York TimesRoom 205 and the “great mimicker”Mr. Markowski, who lives in York, Pa., has been traveling to Catoosa almost every week since early 2019, when he became the general manager of a factory there. He chose the Hampton Inn & Suites, which is owned by Hilton, because it is about six miles from the factory.His first inkling that something was wrong came soon after he checked into Room 205 on the evening of March 14, when he struggled to fall asleep. But he dismissed it as just another bad night, just as he dismissed the feeling of being unusually tired the next day. It was only the next night, back in Room 205, that he could no longer deny there was something wrong.“I felt kind of drunk or something,” he said.He vaguely recalls descending to the lobby to ask if there might be something wrong with the room. It is not clear whether the front desk clerk knew that two other guests had recently called 911 from Room 205. One guest was throwing up and the other had chest pain, according to Mr. Benton, Catoosa’s fire chief.“They went to the hospital,” Mr. Benton said, referring to the two earlier guests. “The hospital turned them loose.”It’s common for hotel staff and doctors to miss the signs of carbon monoxide poisoning, experts say. This is partly because the symptoms — headache, dizziness, weakness, shortness of breath, nausea, vomiting, chest pain, confusion, blurred vision, tingling of the lips — could be caused by so many things.“That’s why they call it ‘the great mimicker,’” said Charon McNabb, a co-founder of the National Carbon Monoxide Awareness Association, a nonprofit based in Bloomfield Hills, Mich.Diagnostic confusion also seemed to have played a role in the Sandals case. The night before they were supposed to check out, two of the people who died, Robbie Phillips, 65, a travel adviser who was actually one of the top sellers for Sandals, and her husband, Michael, 68, visited a medical facility complaining of nausea and vomiting, according to local authorities. Donnis Chiarella, 65, who was staying on the other side of the wall, also visited a clinic, her son told ABC News. All returned to their adjoining beachfront villas, where the Phillipses and Ms. Chiarella’s husband, Vincent, 64, were found unresponsive the next morning according to local authorities. Later that day, all three were pronounced dead. Ms. Chiarella, who had to be hospitalized, was the lone survivor.Further complicating diagnosis is the fact that there often aren’t any major hints before the invisible, odorless gas renders someone too disoriented to take action, said Patrick Morrison, the chief of field services for the International Association of Fire Fighters, the largest union of firefighters and paramedics in the United States. He said his union supports requiring detectors in all hotel sleeping quarters for this reason.“If you cannot get out to fresh air, you’ll be overcome by it,” Mr. Morrison said. “That’s why people die in their sleep.”Mr. Markowski returned to his room, where at some point he recalls lying on the floor screaming.Fuel and a bird’s nestCarbon monoxide is released when a device burns a fuel such as gas, oil, propane, kerosene, wood or charcoal. The most common causes of carbon monoxide poisoning in hotels are boilers and heaters used to warm swimming pools and water for an entire wing, said Dr. Lindell K. Weaver, who specializes in carbon monoxide poisoning at Intermountain Healthcare in Salt Lake City. Gas dryers, fire places, portable gas-powered pool cleaning devices and portable generators are other sources of carbon monoxide leaks.If these devices are working properly — or, in the case of generators, if they are used in a safe location outside — they shouldn’t pose a danger. Carbon monoxide, in tiny amounts, will exit through the exhaust vent. Problems typically occur when the device malfunctions or the vent is blocked or broken. In Mr. Markowski’s case, fire reports identified a bird’s nest plugging the vents in the room with the hot water tanks.The gas can follow air currents through vents, tiny holes and even dry wall, sometimes ending up far away from the original source of the leak. In this case, the gas likely entered Room 205 through holes and crevasses in the floor, according to fire authorities.Filling a room with carbon monoxide causes an effect similar to removing oxygen from the air. That’s because when people breathe in carbon monoxide, it binds with hemoglobin in the blood, causing less oxygen to get transported to vital organs such as the brain and heart.A missed 7:30 meetingEarly on the morning of March 16, Jason Morgan, the plant manager at the factory, learned that his boss, Mr. Markowski, had failed to show up to a 7:30 a.m. meeting. Calling and texting did not elicit a response.Upon arriving at the hotel, Mr. Morgan spotted the Kia Soul Mr. Markowski always rented outside. After convincing the woman at the front desk to let him into the room, he found his boss curled up in a fetal position on the floor.“He couldn’t talk. He didn’t know where he was at,” he said.Fire fighters responding to Mr. Morgan’s call realized that this was their third call to Room 205 in recent weeks and pulled out a carbon monoxide detector. Most in-room alarms are calibrated to go off at levels at which people could be injured if they stay in the room — somewhere around 70 parts per million for more than an hour or 400 p.p.m. for more than four minutes, said Dr. Weaver. Mr. Markowski’s room was at 764 p.p.m., according to Fire Department reports. The water heater room registered at 1,500 p.p.m.At the hospital, doctors screened Mr. Markowski’s blood for the percentage of red blood cells bound with carbon monoxide — the level is affected by the severity of the leak to which a person has been exposed and the length of their exposure. A normal reading is around 2.5 percent; 50 percent is almost always fatal; people with heart disease or lung disease often die at around 35 percent, said Dr. Weaver. Mr. Markowski’s blood registered at 37.2 percent, according to medical reports. He said that doctors told him he was lucky to be alive.“I’m 44 years old and I’m in pretty good shape, so maybe that helped me,” he said.Among those who are poisoned, about 30 to 50 percent experience lasting effects including cognitive issues and heart damage, said Dr. Weaver, who travels with a portable carbon monoxide detector.Isolated incidents or a systemic problem?In Mr. Markowski’s case, in addition to the bird’s nest, two exhaust flues were found detached from the hot water tanks according to fire reports. In contradiction of safety codes in Oklahoma, there was no carbon monoxide alarm near the tanks according to a lawsuit that Mr. Markowski filed against both the hotel owner and Hilton Worldwide Holdings, the company that licenses its name and sets standards for around 2,200 franchise hotels.When contacted for comment, Hilton said that the Catoosa hotel was independently owned and operated and that questions should go to the hotel’s owner. Kalpesh Desai, the owner, said he could not comment because he was involved in active litigation. Josie Hill, a spokeswoman for Hilton, referred questions about carbon monoxide policies to the American Hotel & Lodging Association.The lodging association said that it encourages members to adhere to the International Fire Code, which urges installing detectors near fuel-burning devices.Thomas G. Daly, a consultant and former Hilton employee who has helped the lodging association lobby against stricter carbon monoxide rules, said detectors aren’t the issue. “If equipment isn’t maintained and there is leak, that’s human error,” he said.Requiring detectors in every room is “outrageously expensive,” he said, because it involves not only installing a detector every six years or so but also testing and upkeep. It’s also “the wrong place” to put monitors, Mr. Daly said, given that it’s smarter to catch leaks at the source.But others say that Mr. Markowski’s case is representative of a broken system where it often takes multiple poisoning incidents before leaks are identified and many people only survive because someone happens to come looking for them. It should be on lawmakers and hotel brands to ensure safety, they say.Mr. Desai’s hotel was built in 2010, before Oklahoma required detectors in hotels. The state later required them near fuel-burning devices, but there was no compliance mechanism. Mr. Benton said he didn’t think hotels were aware of the new rule — he didn’t even know of the requirement. Fewer than one-third of states have statutes that outline who is responsible for verifying that hotels have detectors.Regardless, the emphasis on fuel burning devices “is a real red herring,” said Gordon Johnson, a lawyer specializing in carbon monoxide cases. The issue, he said, “is not where the carbon dioxide is created, it’s where it escapes,” and that can be multiple floors or rooms away from the source.An array of portable carbon monoxide monitors, which range in cost from $20 to $200 and have different levels of sensitivity. Kristina Barker for The New York TimesLeslie Lienemann, a lawyer from Minnesota who, with her son, was poisoned by a carbon monoxide leak in a Warren, Mich., hotel in 2019, said the lodging industry’s cost argument is offensive. She and her son wound up in the emergency room because a plumber had incorrectly installed a water heater without an exhaust pipe at a Hawthorn Suites by Wyndham. There was no working detector anywhere at the hotel, according to court documents. They later learned that three years earlier a cleaning woman had stumbled on two guests in another room who’d passed out from a leak.“My son’s life is worth more than the $35 that you’d spend on a carbon monoxide detector,” said Ms. Lienemann, who is suing the company that owns the hotel and the plumbing company that installed the water heater.In a statement, Wyndham Hotels & Resorts said that the hotel is individually owned and operated and required to abide by local laws. Michigan requires carbon monoxide detectors in hotels built after 2009. The owner and the plumber did not respond to calls or emails.Soon after the incident, the hotel replaced the fire alarms in every guest room with combination fire alarm-carbon monoxide detectors that cost $31.99 each.During a deposition, a hotel manager who was not accused of any wrongdoing shared that not long after they were installed, one of the alarms revealed that a new pool heater vent, angled up too high, was releasing carbon monoxide into a guest’s open window.“It was detected, thank God,” said Bassam Mikhael, the manager.Kitty Bennett and Sheelagh McNeill contributed research.52 Places for a Changed WorldThe 2022 list highlights places around the globe where travelers can be part of the solution.Follow New York Times Travel on Instagram, Twitter and Facebook. And sign up for our weekly Travel Dispatch newsletter to receive expert tips on traveling smarter and inspiration for your next vacation. Dreaming up a future getaway or just armchair traveling? Check out our 52 Places for a Changed World for 2022.

The requirement to test for Covid before flying to the United States is hated by many travelers and the U.S. travel industry. But the government shows no sign of getting rid of it.As countries, including Canada and Britain, have lifted their Covid testing requirements for vaccinated visitors in recent months, some Americans are irate that they still have to show a negative test to board a flight back to the United States.Jason Miller, a 37-year-old software engineer who lives in Texas, is so frustrated with the rule that he recently sent letters to the White House and several lawmakers and began encouraging others to do the same. “I support the C.D.C., still wear a N95 mask when in crowds and when I travel,” he said. But, he no longer feels that the rule provides value, in large part because “the testing has not stopped variants from entering the country.”Other travelers have posted similar comments on social media, and a good portion of the travel industry in the United States has made clear it feels the same way.But they have gotten little satisfaction from the Biden administration and public health officials.On May 6, Jen Psaki, then the White House press secretary, said she was “not aware of a timeline” for ending the testing requirement and that the administration would base its decision on a Centers for Disease Control and Prevention recommendation. As to what, specifically, the C.D.C. is using to determine whether testing is still necessary, an agency spokeswoman offered the vague explanation that it “is looking at different indicators” and “evaluating all guidance and orders based on the latest science and state of the pandemic.”The obligatory test has not just created logistical hassles, it has fundamentally shifted the experience of traveling internationally, travelers say.“It was always in the forefront of my mind,” said Danielle Bradbury, 42, who recently spent 12 days in Israel for her job developing medical devices while her husband cared for their two children back in Boston. “Every time I left the hotel, I asked myself, how much risk of not being able to get home am I putting myself in?”Why was testing started in the first place?In January 2021, when the C.D.C. first instituted the rule that all U.S.-bound travelers 2 years and older had to show a negative test or proof of recovery before boarding a flight, the United States joined a sea of countries experimenting with different ways to slow the virus’s spread across borders. A statement from the State Department announcing the requirement played up the difficulty in getting a test abroad, suggesting that the rule also aimed to discourage Americans from traveling internationally. At that point fewer than 10 percent of Americans were vaccinated and case counts were rising, hitting a record of more than 300,000 new cases on Jan. 8.Testing was not the first travel limitation the United States had deployed. In the winter of 2020, President Trump banned visitors from China, much of Europe, Brazil and Iran. When President Biden took office he layered the testing requirement on top of the travel bans. (He also expanded the ban to India.)In late 2021, the United States pivoted away from country-specific bans and doubled down on testing, shortening the window from within three days of travel to one day, even for vaccinated Americans. By then it had become clear that vaccinated people could also spread the coronavirus. (Most unvaccinated visitors from abroad were prohibited from entering the country, even with testing.)How effective has the policy been?It depends how you define success, said Jeremy Goldhaber-Fiebert, a professor of health policy at Stanford University. If success was reducing the number of infected people who flew to the United States, he said, the testing requirement achieved that.“It certainly prevented people who tested positive from getting on planes and it almost certainly prevented some amount of transmission on aircraft and in airports,” he said.The exact number of infected people who were prevented from boarding planes is unknown, however, because no one tracks whether a passenger cancels a flight because of Covid. Most of the evidence is anecdotal; lots of people have stories about testing positive before flying home.If success means keeping new variants out of the country, then it failed, said Dr. William Omrice, the chair of lab medicine and pathology at the Mayo Clinic.“The reality is that none of these measures have prevented the rapid global spread of any variant of concern,” he said.But if success was not preventing the arrival of new variants, but instead delaying their arrival so that hospitals and authorities could be more prepared, then it may have worked. Mark Jit, a professor of vaccine epidemiology at the London School of Hygiene and Tropical Medicine, who has studied the effectiveness of travel requirements, said that this is what testing does well.“Testing can prevent the peak from being reached so quickly,” he said.Still, once a variant is already widespread in a country, he found, a travel test has little effect.Why are many countries getting rid of testing requirements now?Explanations from authorities include readiness to enter a new phase of the pandemic, high vaccination rates and a determination that new variants are manageable.“The current variant is making people less ill and the number of people being admitted to intensive care is limited,” the Netherlands government said in a typical statement in March, as it ended travel testing, among other Covid-related recommendations.What’s the argument for getting rid of the U.S. requirement?The primary argument is that it’s not doing enough good to rationalize the hassle.Dr. Tom Frieden, who was the C.D.C. director during the Ebola outbreak of 2014, was among those who made this point. “Between super-effective vaccinations that we have and Paxlovid, which is a super-effective treatment, Omicron is less deadly than flu most years and we don’t require people to test for flu before they get on a plane,” he said. “If a more dangerous variant emerges,” he noted, “that’s a very different situation.”Others argue that it doesn’t make sense to inconvenience so many people for a system that’s full of holes. Antigen tests — one option for travelers to the United States — are notoriously unreliable in the early stage of infection, said Anne Wyllie, a microbiologist at the Yale School of Public Health. For this reason she called the requirement “hygiene theater.”The testing requirement is not just annoying for travelers, it’s economically damaging, according to the U.S. Travel Association, a trade group. In a recent letter to Dr. Ashish K. Jha, the White House Covid coordinator, signed by more than 260 businesses, including airlines, cruise operators, casinos, tourism boards, Disney Parks and a zoo, the group said “the economic costs associated with maintaining the measure are significant.”“Given the slow economic recovery of the business and international travel sectors, and in light of medical advancements and the improved public health metrics in the U.S., we encourage you to immediately remove the inbound testing requirement for vaccinated air travelers,” the group wrote.A survey commissioned by the group found that 46 percent of international travelers would be more likely to visit the United States without the requirement. A similar survey by the Points Guy, a site that specializes in traveling with credit card points and miles, found that more than half of its participating readers would be more likely to travel abroad without the requirement.What’s the argument for keeping the policy?Meegan Zickus, who runs a Facebook group for people with weakened immune systems, said that testing has become more important since the mask requirement went away. Without a testing requirement, most travelers are not going to bother to test or stay home, even if they suspect that they are infected, she said.“Judging by the past two years, the only way to protect others is some type of enforced testing,” she said, because “the moral compass points directly to self.”Dr. Seema Yasmin, a public health doctor and the director of the Stanford Health Communication Initiative, echoed this point. “I would say that it can give a high level of reassurance when 75 percent of people are not wearing a mask and might even be coughing and sneezing loudly,” Dr. Yasmin said.(Though airplane ventilation systems appear to significantly mitigate spread of the coronavirus, research suggests that people sitting within a few rows still pose a risk to one another.)“Some testing is better than none,” said Nathaniel Hafer, a molecular biologist at the UMass medical school.Many countries also use testing to incentivize vaccination by waiving the requirement for vaccinated people, said Meghan Benton, a research director at the Migration Policy Institute, which tracks travel requirements. The United States encourages vaccination in its own way by prohibiting most unvaccinated visitors from abroad from entering.Could a lawsuit end testing the way it did the mask mandate?Given that there are currently at least four pending lawsuits that challenge the international testing requirement, some wonder whether it might be struck down by a judge’s decision, as the requirement to wear a mask on airplanes and other forms of transport was in April.Lawrence O. Gostin, a professor of global health law at Georgetown Law, does not think so. The C.D.C. can require testing from visitors entering the country from abroad because of the Public Health Service Act, which was explicitly created to prevent the introduction of dangerous infectious diseases in the United States, he said.The rule, he said, “would be exceedingly difficult to successfully challenge in the courts, even for the most conservative judges.”52 Places for a Changed WorldThe 2022 list highlights places around the globe where travelers can be part of the solution.Follow New York Times Travel on Instagram, Twitter and Facebook. And sign up for our weekly Travel Dispatch newsletter to receive expert tips on traveling smarter and inspiration for your next vacation. Dreaming up a future getaway or just armchair traveling? Check out our 52 Places for a Changed World for 2022.

The requirement to test for Covid before flying to the United States is hated by many travelers and the U.S. travel industry. But the government shows no sign of getting rid of it.As countries, including Canada and Britain, have lifted their Covid testing requirements for vaccinated visitors in recent months, some Americans are irate that they still have to show a negative test to board a flight back to the United States.Jason Miller, a 37-year-old software engineer who lives in Texas, is so frustrated with the rule that he recently sent letters to the White House and several lawmakers and began encouraging others to do the same. “I support the C.D.C., still wear a N95 mask when in crowds and when I travel,” he said. But, he no longer feels that the rule provides value, in large part because “the testing has not stopped variants from entering the country.”Other travelers have posted similar comments on social media, and a good portion of the travel industry in the United States has made clear it feels the same way.But they have gotten little satisfaction from the Biden administration and public health officials.On May 6, Jen Psaki, then the White House press secretary, said she was “not aware of a timeline” for ending the testing requirement and that the administration would base its decision on a Centers for Disease Control and Prevention recommendation. As to what, specifically, the C.D.C. is using to determine whether testing is still necessary, an agency spokeswoman offered the vague explanation that it “is looking at different indicators” and “evaluating all guidance and orders based on the latest science and state of the pandemic.”The obligatory test has not just created logistical hassles, it has fundamentally shifted the experience of traveling internationally, travelers say.“It was always in the forefront of my mind,” said Danielle Bradbury, 42, who recently spent 12 days in Israel for her job developing medical devices while her husband cared for their two children back in Boston. “Every time I left the hotel, I asked myself, how much risk of not being able to get home am I putting myself in?”Why was testing started in the first place?In January 2021, when the C.D.C. first instituted the rule that all U.S.-bound travelers 2 years and older had to show a negative test or proof of recovery before boarding a flight, the United States joined a sea of countries experimenting with different ways to slow the virus’s spread across borders. A statement from the State Department announcing the requirement played up the difficulty in getting a test abroad, suggesting that the rule also aimed to discourage Americans from traveling internationally. At that point fewer than 10 percent of Americans were vaccinated and case counts were rising, hitting a record of more than 300,000 new cases on Jan. 8.Testing was not the first travel limitation the United States had deployed. In the winter of 2020, President Trump banned visitors from China, much of Europe, Brazil and Iran. When President Biden took office he layered the testing requirement on top of the travel bans. (He also expanded the ban to India.)In late 2021, the United States pivoted away from country-specific bans and doubled down on testing, shortening the window from within three days of travel to one day, even for vaccinated Americans. By then it had become clear that vaccinated people could also spread the coronavirus. (Most unvaccinated visitors from abroad were prohibited from entering the country, even with testing.)How effective has the policy been?It depends how you define success, said Jeremy Goldhaber-Fiebert, a professor of health policy at Stanford University. If success was reducing the number of infected people who flew to the United States, he said, the testing requirement achieved that.“It certainly prevented people who tested positive from getting on planes and it almost certainly prevented some amount of transmission on aircraft and in airports,” he said.The exact number of infected people who were prevented from boarding planes is unknown, however, because no one tracks whether a passenger cancels a flight because of Covid. Most of the evidence is anecdotal; lots of people have stories about testing positive before flying home.If success means keeping new variants out of the country, then it failed, said Dr. William Omrice, the chair of lab medicine and pathology at the Mayo Clinic.“The reality is that none of these measures have prevented the rapid global spread of any variant of concern,” he said.But if success was not preventing the arrival of new variants, but instead delaying their arrival so that hospitals and authorities could be more prepared, then it may have worked. Mark Jit, a professor of vaccine epidemiology at the London School of Hygiene and Tropical Medicine, who has studied the effectiveness of travel requirements, said that this is what testing does well.“Testing can prevent the peak from being reached so quickly,” he said.Still, once a variant is already widespread in a country, he found, a travel test has little effect.Why are many countries getting rid of testing requirements now?Explanations from authorities include readiness to enter a new phase of the pandemic, high vaccination rates and a determination that new variants are manageable.“The current variant is making people less ill and the number of people being admitted to intensive care is limited,” the Netherlands government said in a typical statement in March, as it ended travel testing, among other Covid-related recommendations.What’s the argument for getting rid of the U.S. requirement?The primary argument is that it’s not doing enough good to rationalize the hassle.Dr. Tom Frieden, who was the C.D.C. director during the Ebola outbreak of 2014, was among those who made this point. “Between super-effective vaccinations that we have and Paxlovid, which is a super-effective treatment, Omicron is less deadly than flu most years and we don’t require people to test for flu before they get on a plane,” he said. “If a more dangerous variant emerges,” he noted, “that’s a very different situation.”Others argue that it doesn’t make sense to inconvenience so many people for a system that’s full of holes. Antigen tests — one option for travelers to the United States — are notoriously unreliable in the early stage of infection, said Anne Wyllie, a microbiologist at the Yale School of Public Health. For this reason she called the requirement “hygiene theater.”The testing requirement is not just annoying for travelers, it’s economically damaging, according to the U.S. Travel Association, a trade group. In a recent letter to Dr. Ashish K. Jha, the White House Covid coordinator, signed by more than 260 businesses, including airlines, cruise operators, casinos, tourism boards, Disney Parks and a zoo, the group said “the economic costs associated with maintaining the measure are significant.”Travel Trends That Will Define 2022Card 1 of 7Looking ahead.

Despite pressure from airlines and industry groups, the Biden administration extended the requirement to wear masks while traveling on public transportation through May 3.Despite great pressure from airlines, the hospitality industry and Republican lawmakers to lift the rule requiring masks on planes and other public transportation, the Centers for Disease Control and Prevention extended the federal transportation mask requirement for two weeks on Wednesday, five days before it was set to expire. The mask mandate now expires May 3, if it is not extended yet again.Dr. Ashish K. Jha, the new White House Covid response coordinator, said in an interview that the additional time will allow the C.D.C. to assess whether BA.2, a subvariant of the coronavirus, is going to become a “ripple or a wave” in the United States. The C.D.C. will use that information to determine whether the mandate should be extended further, he said.“If the infection numbers are relatively low, as they are right now, then I think it’s reasonable to remove mask mandates,” he said, emphasizing that it’s a C.D.C. decision.In a statement announcing the extension of the divisive rule, the C.D.C. said BA.2 now makes up more than 85 percent of new U.S. virus cases.“Since early April, there have been increases in the 7-day moving average of cases in the U.S.,” the agency said. “In order to assess the potential impact the rise of cases has on severe disease, including hospitalizations and deaths, and health care system capacity, the C.D.C. order will remain in place at this time.”In recent days, new U.S. cases have started ticking up again. As of Tuesday, the nation was reporting more than 31,000 new cases a day on average, 8 percent more than two weeks earlier, according to a New York Times database, though the case counts have not approached the peak seen in the winter Omicron surge. Reported cases may be an undercount of the virus’s true spread to some degree, since access to at-home tests has increased and the results of such tests are often not officially reported.It’s not yet clear how severe the impact of these cases will be, Dr. Jha said, noting that BA.2 has caused far more hospitalizations and deaths in the United Kingdom than it has in Israel, two countries where it appeared earlier than in the United States and where it spread widely.“So the question is which path is America going to follow; will it follow the U.K. path or the Israeli path?” he asked.In recent months, airlines and the hospitality industry have been lobbying the White House to overturn both the mask rule and the requirement to test before returning to the United States from abroad. In one of the most recent letters, dated April 8, Airlines for America, an industry group representing eight airlines; the U.S. Travel Association, a trade group representing more than 1,000 public and private organizations catering to business and leisure travelers; the U.S. Chamber of Commerce, the nation’s largest business lobbying group; and the American Hotel and Lodging Association, which represents thousands of hotels, sent a letter to Dr. Jha, arguing that what they see as unnecessary measures were hurting the country economically.“While the public health benefits of these policies have greatly diminished, the economic costs associated with maintaining these measures are significant,” they wrote.On Wednesday, shortly before the C.D.C. announcement, Airlines for America sent yet another letter to Dr. Walensky, the C.D.C. director, pushing for a detailed explanation of why masks are still necessary on planes.“It is very difficult to understand why masks are still required on airplanes, but not needed in crowded bars and restaurants; in packed sports arenas; in schools full of children; or at large indoor political gatherings,” Nicholas E. Calio, the president of the group, wrote.But airlines are unlike virtually all other indoor settings, said David Freedman, the president-elect of the American Society of Tropical Medicine and Hygiene, because you can’t easily leave.“The difference with other indoor settings is that on an airplane you are trapped until the end of the flight or until everyone disembarks,” he said.Dr. Jha made a similar point.“If that person sitting next to you is coughing and clearly infected, you can’t get up and move,” he said, adding, “even if they have the best ventilation, you will not be fully protected.”Opponents of the mask mandate often point to the advanced ventilation systems on airplanes, saying they practically eliminate the risk of transmission.“It’s low, but there is no zero risk situation on an airplane,” said Dr. Aisha Khatib, the chair of a group focused on responsible travel for the International Society of Travel Medicine, adding that the risk goes up in a surge situation and while getting on and off planes if the ventilation system is not on. “Masks will definitely decrease your risk of transmission,” she said.Canada, where Dr. Khatib lives, is grappling with similar situation, she said. Masks are still required on airplanes and in airports there, but as an expiration date approaches for Canada’s mask mandate, cases have been rising in some parts of the country.By many accounts, enforcement has been one of the most challenging aspects of the mask mandate in the United States, with many passengers verbally and even physically assaulting flight attendants who reminded them to cover their nose and mouth. In 2021, more than 4,000 mask-related incidents were reported to the Federal Aviation Administration.Ahead of the decision, major unions representing flight attendants and Transportation Security Administration employees, two groups that have to deal with enforcing the rule, declined to take a stance.“Whatever the agency puts in place, we have to comply with it,” said Hydrick Thomas, the president of the union that represents T.S.A. employees, on Tuesday. He added that he believes that masks protect his employees, their families and “the flying public.”The extension provoked applause from some travelers and commuters, with some arguing that it should remain in place even longer.“The C.D.C. is extending the mask mandate for public transport for two weeks,” Dr. Lucky Tran, a scientist and activist who was one of the organizers of the March for Science in 2017, wrote on Twitter. “That’s not enough. Millions rely on public transportation every day to get to work or access essential services. While we are in a pandemic, we need mask mandates to keep society open and accessible to all.”Ari Fleischer, a media consultant who served as a White House spokesman for President George W. Bush, was among the many who took an opposite stance on the same platform.“This is absurd,” he wrote on Twitter on Wednesday. “Either there is a public health threat requiring all citizens to wear masks everywhere, or there’s not.”Follow New York Times Travel on Instagram, Twitter and Facebook. And sign up for our weekly Travel Dispatch newsletter to receive expert tips on traveling smarter and inspiration for your next vacation. Dreaming up a future getaway or just armchair traveling? Check out our 52 Places for a Changed World for 2022.

Should mask rules on planes be lifted? Several British airlines have just suspended the requirement, but in the United States, the mandate, to be reviewed next month, remains. Here’s a look at where things stand.Air travel has been one of the last holdouts for strict pandemic mask requirements. In the United States, for example, the mask mandate — which was recently extended to April 18, when it comes up for review again — is still enforced. Over the last year, 922 of those who didn’t wear masks received fines from the Transportation Security Administration, according to a report by the Government Accountability Office.But there are hints that the tide may be turning: Within the past few weeks, Danish airports and London’s Heathrow Airport have lifted their mask requirements, as have several major British airlines.Some airline employees in England rejoiced at their reclaimed freedom from enforcing mask rules at 30,000 feet. “First flight done without a mask and it was an absolute dream,” a woman, who identified herself as a flight attendant from Yorkshire, England, on her social media accounts, recently wrote on Twitter, alongside a photo of her fully visible smile. In the United States, the International Air Transport Association, which represents nearly 300 airlines, and the U.S. Travel Association, an industry group, have been lobbying the White House not to extend the mandate further, saying it’s difficult to rationalize mask rules in the sky, given that authorities have already lifted them in other indoor locations. Republican lawmakers, who recently sued the Centers for Disease Control and Prevention to end the mask mandate for air travel, call the rule “arbitrary.” But some travel health experts and passengers say airplane cabins and airports should take a more careful approach.“It was very unsettling,” said Rebecca Kift, 37, a clinical biochemist from Leeds, England, who had no idea that the British airline TUI Airways Limited had lifted its mask requirement until she boarded her flight to Manchester from Spain’s Gran Canaria island last Monday. Because her mother is being treated for cancer, she has spent months avoiding crowded indoor situations. But there she was with four hours ahead of her in a cabin full of unmasked flight attendants and mostly unmasked passengers. “I don’t think it’s fair,” she said.Here is a look at the confusing state of mask wear in the sky.What just happened in England?Unlike the United States, England never instituted a governmental mask mandate for air travel. Nonetheless, most British airlines and airports began requiring masks in June 2020, when Britain started mandating masks on other forms of transport.Over the past couple of weeks, as parts of Britain have lifted other types of travel and mask requirements, some airports and airlines have suspended their mask rules, among them, London’s Heathrow Airport, British Airways and Virgin Atlantic. Both airlines said wearing a mask was a “personal choice,” and clarified that the shift only applies while flying to or from destinations where there are no mask requirements, such as England and Barbados.They are not the first airlines to permit bare faces. Two additional British airlines, Jet2 and TUI Airway, had previously dropped their mask requirements, and passengers began flying without face coverings throughout Scandinavia last October.What determines if you have to wear a mask on a particular route?If the departure and destination countries have different restrictions, the country with the stricter rule sets the policy in the sky. Individuals flying between England and Northern Ireland on TUI Airways, for example, would not have to wear a mask, but individuals flying between England and the United States on that same airline would have to wear one.Beyond England, Northern Ireland, Norway and Barbados, destinations that do not currently have mask requirements in the air include Mexico, St. Lucia, the Bahamas and Jamaica. The United States, Scotland, Italy and China are among the many countries that continue to require masks on planes.Airport rules may be stricter than plane rules on a given route, meaning a traveler might have to put on a mask upon arrival. Airports in Norway, Denmark and England have been outliers in lifting mask requirements, according to the Airports Council International, a trade organization representing nearly 2,000 airports.When can I stop flying with a mask in the United States?Maybe on April 19, if — and that’s a big if — the White House does not extend the federal mask mandate further. Even flight attendants are divided on whether the mandate should be extended again, with some saying that the mask rule is not worth it, given the problems enforcing it, while others argue that the rule is critical to keeping medically vulnerable travelers safe.Should Covid case counts affect mask mandates?It depends on whom you ask.Across the world, case count numbers vary. In recent weeks, case numbers have dipped to their lowest level since June in the United States. Canada is also down to its lowest number of cases since December. But in many other places, cases are rising. As England moved away from airport and airline mask mandates on March 16, case counts hit their highest point in nearly a month. Meanwhile, a highly transmissible subvariant known as BA.2 is pummeling some parts of Asia and Europe. And on Sunday, Dr. Anthony S. Fauci, the Biden Administration’s top adviser on the pandemic, predicted that the United States would eventually see a similar “uptick” of BA.2 cases.“Covid is not over,” said Leonard Marcus, the director of Harvard’s Aviation Public Health Initiative, which produced a report that some airline executives have used to rationalize ending mask requirements. Dr. Marcus said that it’s too soon for him to have an opinion on whether BA.2 merits an extension of the federal mask mandate. But once lifted, he said, a mask mandate will be difficult to reinstate.Some proponents of ending mask mandates argue that so long as vaccines are preventing serious disease, case counts are irrelevant, because most international travelers are vaccinated.In a statement announcing the end of its mask requirement last week, Heathrow Airport embodied this line of thinking, mentioning “the strong protection provided by vaccination programs around the world” and an embrace of a “move towards learning to live with Covid longer term.”But proponents of mask mandates also point out that not everyone on a plane can count on vaccines protecting them and the people they live with from severe Covid infections.Don’t advanced air filtration systems on airplanes provide enough protection?The advanced filtration systems on many planes refresh the air every two to three minutes. Therefore the risk of being infected should be lower than in other packed indoor settings, many of which no longer require masks, airlines have argued. (It should also be lower than in the airport or on crowded bridges to a plane, where you cannot count on great ventilation systems, according to Dr. David Freedman, the president-elect of the American Society of Tropical Medicine & Hygiene.)Travel testing requirements have also made an already low-risk environment for transmission safer.But if you’re sitting close to a contagious person, you could still end up breathing in recently emitted virus before it makes it into the air filtration system, some researchers have pointed out. “There is some evidence that passengers within two rows of an index case are at higher risk,” said Patricia Schlagenhauf, a professor of travel medicine at the University of Zürich.Is masking on airplanes really effective?Yes, travel experts say. While the consensus among researchers who focus on this area has been that air travel is quite safe, there are examples of coronavirus transmission on planes; most occurred before mandatory mask policies arrived, said Dr. Aisha Khatib, the chair of a group focused on responsible travel for the International Society of Travel Medicine.“It may be argued that the most effective mitigation measure to date has been mandatory masking in-flight,” said Dr. Khatib.Dr. Freedman echoed this point. Once the mandate goes, he said, “I’m still going to wear my N95 the whole flight.”Some airlines and airports that have lifted mask mandates have also emphasized masks’ value. Emma Gilthorpe, Heathrow’s chief operating officer, said that even without the requirement she still would “recommend wearing them.”Should I wear one if I’m sniffling or tested positive?The C.D.C. continues to advise people to quarantine for five days if they test positive, regardless of symptoms. But, inevitably, some people who test positive will still get on a plane. To reduce the risk of transmission, they should wear a good mask.In East Asia, long before the pandemic, wearing a mask in public if a person had a cold or flu was standard etiquette, noted Emma Teng, a professor of Asian Civilization at Massachusetts Institute of Technology, who had studied the history of masks.Dr. Teng believes that the pandemic could have a lasting effect on how Americans approach masks. “I think it’s been relatively normalized for people to wear masks in public settings if they are feeling under the weather,” she said.What about babies and toddlers?Parents of children under 5 have expressed mixed feelings about the mask mandate in the United States. The coronavirus vaccine is currently only available to children over 5, giving many parents anxiety about placing their little one, who may be too young to wear a mask, amid so many unmasked travelers. On the flip side, many parents consider the current rule, which requires children as young as 2 to wear a mask, unreasonable.“Under 3 is absolutely unrealistic to do the entire time,” said Amanda Pendarvis Lacy, 31, who got kicked off a plane with her then 2-year-old son in September after he repeatedly pulled down his mask. She’s not sure where she stands on a mask mandate for adults, but “I’d be relieved if he didn’t have to wear it,” she said.Follow New York Times Travel on Instagram, Twitter and Facebook. And sign up for our weekly Travel Dispatch newsletter to receive expert tips on traveling smarter and inspiration for your next vacation. Dreaming up a future getaway or just armchair traveling? Check out our 52 Places list for 2022.

The requirements for entering foreign countries during the pandemic can be confusing and ever-changing, especially when it comes to boosters. Here’s what to expect.John Henretta had been looking forward to his June hiking trip to Switzerland for months.Recently he noticed something surprising: Starting in February, travelers would need to show that they’d gotten their last shot within 270 days of entering Switzerland.Mr. Henretta, who is 75 and lives in Gainesville, Fla., calculated forward from when he got his booster in September. That seemed to mean that any time after June 22, he would no longer be considered fully vaccinated. According to the Swiss consulate in Atlanta, Americans must be fully vaccinated to enter the country, which suggested that he would be prohibited from entering the country in late June when his tour began. Could that really be, he wondered?The answer is yes. But arriving at that conclusion was not easy, given that a number of government and airline sites seemed to contradict one another.“You have to be considered fully vaccinated,” said Divine Bonga, the head of Switzerland’s media team for tourism from North America. If American or Canadian tourists got their booster or second shot more than 270 days before their arrival — a situation that will become more common in late summer and fall — “you cannot enter the country,” she said, adding that the rules could change again before then.Mr. Henretta said he thought he was doing the smart thing by getting his booster when he did. “The real irony is that I made the earliest approved appointment and then it comes back to bite me,” he said.Switzerland is an outlier in limiting boosted visitors in this way. But other governments have also begun to put time limits on how long a visitor is considered fully vaccinated with just one or two doses.Mr. Henretta’s situation offers a particularly thorny illustration of just how confusing and changeable vaccination rules are becoming. Here is a look at how some of these new requirements are playing out across the world.Do other countries put a time limit on vaccinations and boosters?Yes, but most still allow visitors into the country.Malta, for example, puts a time limit on shots. Those who have received two doses must have gotten their last shot within three months. Boosters expire after nine months. But unlike the situation in Switzerland, it’s still possible for travelers with a timed-out vaccine to enter. Those individuals are treated as if they are unvaccinated, meaning that they must present a negative P.C.R. test result and quarantine at a designated facility for 14 days after arrival.Similarly, in Bulgaria, vaccination certificates are considered valid from the 15th to the 270th day after the last dose, with no apparent exception for boosters. But because unvaccinated people may enter, those who have timed out must simply show a negative Covid-19 test result to enter.Israel’s policy is currently the closest to Switzerland’s, but it is likely to change yet again. A second or third shot is only valid for six months, so under those rules someone who got their booster in December wouldn’t be able to enter come June or July unless a fourth shot became available. But according to Tourist Israel, a tour provider which closely tracks the rules, the country is expected to waive time limits on boosters in March. (Exceptions are currently made for people who can show a certificate of recovery from Covid.)How do other types of vaccine expiration dates affect travelers?In some cases — for example, in France and Estonia — there are time limits on the validity of full vaccinations without a booster (nine months for France and a year for Estonia). Because these countries prohibit tourists from the United States and some other countries from visiting if they are not fully vaccinated, that means that a traveler who got their second Moderna shot before May 17 can’t enter France unless they first get a booster. Having a booster makes things easier when it comes to timing constraints since these places treat boosters as a sort of expiration-free additional dose.Ireland and the Czech Republic treat anyone who got their second dose more than nine months ago as if they are unvaccinated. Croatia takes the same approach, but makes it more than a year. But their governments do not prohibit unvaccinated American tourists from entering. A traveler who got their second Moderna shot before May 17 could take a test or get a booster to enter these countries.Are there any countries that require being boosted for entry?Not currently.Austria, for example, does not consider someone fully vaccinated unless they’ve had the booster. But travelers who do not meet that requirement can still enter the country by obtaining a negative result from a P.C.R. test.Why do countries impose these time limits?One reason, Ms. Bonga said, is to encourage people to get boosters.There is also some evidence that coronavirus vaccines stop providing as much protection as time goes on.What if different entities and sites are giving me conflicting information?This may happen. Getting the answer to Mr. Henretta’s query about traveling to Switzerland, for example, was far from straightforward. The fact that the last shot of a vaccine timed out after 270 days was clear, but some sources could not agree on whether unvaccinated Americans could enter the country or not. A representative for the country’s information line for travelers suggested that they could; in that case, Mr. Henretta could simply provide a negative test result. Swiss International Air Lines initially offered the same answer on its site and by email. But the State Secretariat for Migration, two representatives from the Swiss tourism office, and the official Swiss entry tool took a different position: Unvaccinated and partially vaccinated American tourists could not enter. Eventually, a representative from Swiss International Air Lines clarified that although unvaccinated visitors from some countries can enter with a test, unvaccinated Americans cannot because the United States is currently classified as a high-risk country.In the end, almost everyone was finally in agreement: Mr. Henretta could not take his long booked flight unless a fourth shot becomes available or the rules change, which happen fairly frequently.Typically airlines are the best entities to verify requirements with, given that their employees are responsible for deciding who meets entry requirements. (The New York Times also keeps guidelines for American travelers going abroad, which includes links to government sites that can be reviewed.)So what should early booster adopters do if they’ve already planned trips in the summer or fall?Keep checking the rules for their destinations, as they change frequently.In the case of Switzerland, there is a chance the country will change its policy before late June, when early booster adopters begin to find that their last shot is considered too old. In Mr. Henretta’s case, he considered moving up his flight so that he’d arrive several days before his group hiking tour began. But this made him nervous because, as of last week, Switzerland still required proof of vaccination — using the same dating system — to enter a wide range of establishments including restaurants. (In an announcement this week, Switzerland said it has lifted most of its Covid-related restrictions, including vaccination requirements at restaurants, but the entry requirements for Americans and other third country nationals have not changed.)“It’s their country, they can do what they want,” he said of the approach to boosters. But it no longer seemed like the ideal destination for him. Instead he decided he’d apply his deposit toward a hiking tour in another country.Paige McClanahan contributed reporting from Samoëns, France.Follow New York Times Travel on Instagram, Twitter and Facebook. And sign up for our weekly Travel Dispatch newsletter to receive expert tips on traveling smarter and inspiration for your next vacation. Dreaming up a future getaway or just armchair traveling? Check out our 52 Places list for 2022.

The requirements for entering foreign countries during the pandemic can be confusing and ever-changing, especially when it comes to boosters. Here’s what to expect.John Henretta had been looking forward to his June hiking trip to Switzerland for months.Recently he noticed something surprising: Starting in February, travelers would need to show that they’d gotten their last shot within 270 days of entering Switzerland.Mr. Henretta, who is 75 and lives in Gainesville, Fla., calculated forward from when he got his booster in September. That seemed to mean that any time after June 22, he would no longer be considered fully vaccinated. According to the Swiss consulate in Atlanta, Americans must be fully vaccinated to enter the country, which suggested that he would be prohibited from entering the country in late June when his tour began. Could that really be, he wondered?The answer is yes. But arriving at that conclusion was not easy, given that a number of government and airline sites seemed to contradict one another.“You have to be considered fully vaccinated,” said Divine Bonga, the head of Switzerland’s media team for tourism from North America. If American or Canadian tourists got their booster or second shot more than 270 days before their arrival — a situation that will become more common in late summer and fall — “you cannot enter the country,” she said, adding that the rules could change again before then.Mr. Henretta said he thought he was doing the smart thing by getting his booster when he did. “The real irony is that I made the earliest approved appointment and then it comes back to bite me,” he said.Switzerland is an outlier in limiting boosted visitors in this way. But other governments have also begun to put time limits on how long a visitor is considered fully vaccinated with just one or two doses.Mr. Henretta’s situation offers a particularly thorny illustration of just how confusing and changeable vaccination rules are becoming. Here is a look at how some of these new requirements are playing out across the world.Do other countries put a time limit on vaccinations and boosters?Yes, but most still allow visitors into the country.Malta, for example, puts a time limit on shots. Those who have received two doses must have gotten their last shot within three months. Boosters expire after nine months. But unlike the situation in Switzerland, it’s still possible for travelers with a timed-out vaccine to enter. Those individuals are treated as if they are unvaccinated, meaning that they must present a negative P.C.R. test result and quarantine at a designated facility for 14 days after arrival.Similarly, in Bulgaria, vaccination certificates are considered valid from the 15th to the 270th day after the last dose, with no apparent exception for boosters. But because unvaccinated people may enter, those who have timed out must simply show a negative Covid-19 test result to enter.Israel’s policy is currently the closest to Switzerland’s, but it is likely to change yet again. A second or third shot is only valid for six months, so under those rules someone who got their booster in December wouldn’t be able to enter come June or July unless a fourth shot became available. But according to Tourist Israel, a tour provider which closely tracks the rules, the country is expected to waive time limits on boosters in March. (Exceptions are currently made for people who can show a certificate of recovery from Covid.)How do other types of vaccine expiration dates affect travelers?In some cases — for example, in France and Estonia — there are time limits on the validity of full vaccinations without a booster (nine months for France and a year for Estonia). Because these countries prohibit tourists from the United States and some other countries from visiting if they are not fully vaccinated, that means that a traveler who got their second Moderna shot before May 17 can’t enter France unless they first get a booster. Having a booster makes things easier when it comes to timing constraints since these places treat boosters as a sort of expiration-free additional dose.Ireland and the Czech Republic treat anyone who got their second dose more than nine months ago as if they are unvaccinated. Croatia takes the same approach, but makes it more than a year. But their governments do not prohibit unvaccinated American tourists from entering. A traveler who got their second Moderna shot before May 17 could take a test or get a booster to enter these countries.Are there any countries that require being boosted for entry?Not currently.Austria, for example, does not consider someone fully vaccinated unless they’ve had the booster. But travelers who do not meet that requirement can still enter the country by obtaining a negative result from a P.C.R. test.The Coronavirus Pandemic: Key Things to KnowCard 1 of 3The virus in the U.S.

Even as the variant surges, the seasonal travel rush seems unstoppable, but there are steps you can take to travel more responsibly and mitigate the health risks for yourself — and others.Taylor Allen wanted to be a responsible traveler, but she was finding it difficult.Late last week at least seven people Ms. Allen knew in Brooklyn posted on Instagram that they’d tested positive for the coronavirus. She had not seen any of them in person. But after developing an intense headache and runny nose on Friday, she canceled her Saturday morning flight to Jacksonville, Fla., where she was planning to see her parents and grandparents.Two at-home tests — one Friday and one Saturday — came back negative. But Ms. Allen, 22, who is fully vaccinated but not yet boosted, wanted more official assurance before she rebooked her trip. On Sunday evening, long after her scheduled appointment at an urgent care clinic in Crown Heights, an employee told her and the 30 or so other people waiting for tests in the bitter cold that they’d have to come back at 8 a.m.“I really don’t want to put anyone in danger,” said Ms. Allen, who left the clinic with plans to return again the next day.Even as the number of coronavirus cases is skyrocketing in some parts of the country, largely driven by the Omicron variant, the holiday travel rush appears unstoppable. On Friday, Los Angeles International Airport reported its busiest day since early 2020, and on Sunday, 2.1 million people passed through airports in the United States, nearly twice as many as at this time last year.For those who are determined to keep their travel plans, figuring out how to do so responsibly has never been more confusing. Part of the problem is that testing has been hard to obtain in a timely way, particularly in hard-hit cities like New York. Another key challenge is that many people plan to stay in a house with fully vaccinated friends and family. Now, they are learning that vaccination is far from a guarantee that they won’t infect one another. So what can travelers do?1. Get a boosterOnly one in six Americans have received a booster, according to the Centers for Disease Control and Prevention. Fully vaccinated individuals without a booster are at least twice as likely to test positive as those who received a booster.If you plan to travel over the coming weeks and months, and you’re already fully vaccinated, one of the best ways to be a responsible traveler is to get a booster, said Jeffrey Kahn, the director of the Johns Hopkins Berman Institute of Bioethics.In terms of timing, the data show that the optimal immune response comes about two weeks after the booster, according to Dr. Wafaa El-Sadr, a professor of epidemiology and medicine at the Columbia University Mailman School of Public Health in New York. But many will see some protection within a few days, other experts noted, so getting a third shot today could still benefit those traveling over the holidays.2. Consider the worst-case scenarioWhen deciding what’s responsible in terms of holiday travel, Kelly Hills, a co-founder of Rogue Bioethics, a consulting firm in Boston, advises thinking about “moral injury” and asking whether you are mentally prepared for the consequences if you infect a vulnerable person.That doesn’t have to translate into canceling plans, but it may encourage you to wear an N95 instead of a homemade mask on a plane or to take a test even though it’s a hassle. If you are indoors, unmasked around many people in the days leading up to the trip, you may also want to pay extra to book a separate house or motel room, rather than staying with family or friends.“‘I don’t want to be a spreader’— that should be the motto today,” said Leonard J. Marcus, the co-director of the National Preparedness Leadership Initiative at Harvard University and the director of an initiative focused on public health on flights.Dr. Marcus said that though he’s not aware of any data suggesting children are likely to become infected on planes, he advises parents not to fly with unvaccinated children — if possible — until more is known about Omicron.“If it were my grandchildren, I would postpone,” he said. In general, if someone is wearing a proper mask on a plane, the risk of being infected should be low because the ventilation system is so good, he said.Dr. Anthony Fauci, the nation’s top infectious disease official, told CNBC that he feels safe having his adult children fly to see him over the holidays. He also noted that they are vaccinated.Experts advise getting tested as close to the day of a gathering as possible. If an at-home test is positive, double-check the results with a more accurate P.C.R. test. Above, getting tested in Manhattan.Carlo Allegri/Reuters3. Test as close to the gathering as possibleTesting in many parts of the country is challenging right now.“On a one to 10 scale of hard, it’s a 10,” said Mary Mathurin, 51, outside a testing site in Brooklyn on Sunday evening. As she waited for her name to be called, her cellphone emitted hold music from a call with another facility that had yet to send her P.C.R. results from several days earlier. After around 70 minutes, the call dropped. A few minutes later, a patient care assistant at the Brooklyn site told her the site could not accommodate her. She was supposed to fly to St. Lucia the next morning and was unsure what she was going to do.Many pharmacies and online retailers have sold out of at-home tests. The White House is planning to make 500 million free at-home tests available, but that won’t happen until January. For those who do manage to get a kit, use it as close to your departure date as possible, several experts said.The Coronavirus Pandemic: Key Things to KnowCard 1 of 4The Omicron variant.

In the midst of the holiday season, the Omicron variant has many considering the prospects of getting stuck while traveling. Here’s what you need to know.Millions of Americans are expected to travel over Christmas and New Year’s, with some booking sites, such as Hopper, predicting that even international travel will approach prepandemic levels. As travelers try to decide whether to commit to their plans, many are grappling with the question: What if I test positive even though I’m vaccinated, and get stuck somewhere far from home?It’s not an outrageous question. In 2019, more than 5 million people flew into the United States over the holiday period, according to Customs and Border Protection data. Every person age 2 and up who is returning to the United States from abroad by air — including vaccinated American citizens — has to take a coronavirus test within a day of their flight home. Even if the numbers of those traveling hover far below 2019 levels, some people will have to cancel their flights to the United States because they tested positive.Of course, for people who become severely sick with Covid, the immediate concerns go far beyond getting stuck. Over the past week, an average of 7,052 people around the world — including nearly 1,300 people in the United States — died each day from the coronavirus. For vaccinated people, the implications are generally less dire. Worrying about your inability to board a flight can feel self-indulgent when I.C.U.s in many places are overwhelmed. But from a planning perspective, the consequences are not insignificant.What are the odds of testing positive if you’re vaccinated?Alas, this was difficult to answer even before the Omicron variant popped up in November. While research once put the odds of the average vaccinated American contracting Covid at around one in 5,000 per day, that figure is likely to increase as Omicron spreads. Though much is still unknown about the variant, early indications suggest that it infects vaccinated people at higher rates than previous variants. One small study found that the majority of the 43 people first identified with Omicron in the United States were fully vaccinated when they tested positive. There have been some early indications that the variant might cause milder disease than other variants and scientists expect that it’s less likely to become severe in vaccinated people.Boosters should decrease a vaccinated person’s odds of becoming infected with multiple variants. Early data suggests that booster shots for the Moderna and the Pfizer-BioNTech vaccines offer substantial protection against Omicron, Dr. Anthony S. Fauci, President Biden’s top medical adviser, said Wednesday. Booster shots start having an effect in many people in just a few days, meaning that it’s not too late to reap the benefits even if you’re traveling soon, said Dr. Aaron Milstone, a professor of pediatric infectious disease at Johns Hopkins University School of Medicine, who is studying the immune response to booster doses. Even stronger protection is likely to kick in 10 to 14 days after the shot, he and other experts noted, so the sooner you get one, the better.If I test positive while traveling within the United States, will I have to stay put?When driving across a state border, no one is going to ask you to flash negative test results. Neither states, airlines, airports or most other forms of transportation require negative coronavirus tests from domestic travelers with a few exceptions: Hawaii and the U.S. Virgin Islands. If you do end up testing positive — perhaps because a private gathering requires a test — the responsible course of action would be to isolate yourself from others because you are contagious, said Dr. Emily E. Volk, the president of the College of American Pathologists, an organization of physicians who perform biopsies and diagnose disease.“It’s the morally and ethically correct thing to do,” she said.But in most of America it’s up to the individual to decide how to proceed. The Centers for Disease Control and Prevention advises isolating for at least 10 days after testing positive, even if a person never develops symptoms. In a recent article for The Atlantic magazine, the writer Katharine J. Wu argues that this recommendation is outdated and that vaccinated people should be able to test out of isolation sooner. Dr. David Freedman, the president-elect of the American Society of Tropical Medicine and Hygiene, made a similar point in a recent interview: Once you’ve tested negative, you should feel OK about traveling again, he said.Either way, for better or worse, these are just recommendations. Some employers, educational institutions, states and counties have additional isolation policies, but few locations actively enforce quarantine. Depending on where you tested positive, you might get a call from a contact tracer. Or you might not.So what happens if you test positive while traveling internationally?A crucial step while planning any trip is to familiarize yourself with the points at which you will have to take a test and what would happen if you or someone you were traveling with tested positive, including the length and type of quarantine. In some destinations, the only concrete consequence of a positive test is that you can’t board a flight. In other destinations, health officials might require you to stay in a government hospital for more than 10 days.Pack as if you’re going to get stuck, advised Amy Eckhardt, the owner of World View Adventures, a travel agency based in Buffalo, N.Y. That might mean bringing two additional weeks of medication and your work laptop.Ms. Eckhardt has yet to have a client test positive while abroad, but she’s learned from her own experience. To celebrate her 40th birthday, she spent about a month and a half in Mexico last winter before she had the opportunity to get vaccinated. For the final leg of her trip, she picked a resort in Costa Mujeres that offered free on-site testing and covered the costs of food and lodging during quarantine, if required.When her results came back positive on Jan. 31, she said, hotel employees asked her to put on a “biohazard orange” wristband and to move from her oceanfront room to a basement room in “the quarantine section.” Because she was the hotel’s first guest to test positive, the staff was still figuring out how to handle such situations. Her resort stationed a guard outside her door, and initially she had to move to a new room across the hall every three days, while people in hazmat-like suits and goggles sanitized the room and placed new towels in the bathroom. Fortunately, she never developed any serious symptoms and her primary obstacle was boredom, which she countered by posting detailed updates about the iguana on her patio and other humorous observations in a private Facebook group for travel agents. After completing her 10 days of quarantine, she tested negative and flew back to the United States.How long does it take to test negative?Someone infected with Covid will typically test positive for five to eight days, said Dr. Freedman of the American Society of Tropical Medicine and Hygiene.In rare cases someone might test positive for as long as six weeks, even though the individual is no longer contagious, he said. There is a way to get around this in some cases. Many countries and airlines will accept a certificate of recovery from a doctor or health official in lieu of a test. Erika Richter, a spokeswoman for the American Society of Travel Advisors, a trade organization, urged people to review the C.D.C.’s highly specific requirements for that certificate.The Coronavirus Pandemic: Key Things to KnowCard 1 of 4U.S. surpasses 800,000 deaths.

Most people have become used to making health-risk assessments during the pandemic, but that doesn’t make the decision about whether to travel or cancel easier — especially with a new variant circulating.To cancel or not to cancel. That is the question that travelers are grappling with as the Omicron variant scuttles around the world, reminding people that the pandemic roller-coaster ride is far from over. What’s different this time around is that the holiday travel season is right around the corner, and tourism, in general, has finally started to rebound.Whether the variant, which has been identified in at least 20 countries, is more severe or more transmissible than other forms of the coronavirus will likely remain unknown for at least two weeks. The United States is among the countries that believe that it is a serious enough threat to merit new rules. Soon after researchers in South Africa discovered it, President Biden suspended incoming U.S. travel from eight African nations. On Tuesday, the Centers for Disease Control and Prevention said that the United States would tighten testing requirements, requiring all travelers entering the United States — including returning Americans — to provide negative tests taken within one day of departure instead of the three days now permitted for vaccinated travelers.Though most people are by now experienced with making high-stakes health-risk assessments in the face of incomplete information, that doesn’t make the decision about whether to travel or not easy.Omicron variant pls don’t ruin my 2022 travel plans.— mabintou (@mabintou) November 30, 2021
Courtney Niebrzydowsk, an international travel risk analyst at the University of Denver, said she urges people to ask themselves two primary questions when they consider traveling: 1. Can this travel be postponed? and 2. How flexible can you be?She also urges people to think through all the scenarios that could emerge if they travel — like testing positive, facing a canceled return flight or learning last minute that their destination country has expanded its quarantine requirement — and map out detailed contingency plans, including costs, missed obligations and how to approach health care. Often, she said, after going through this exercise, people have “less appetite for travel.”The C.D.C. advises against international travel until a person is fully vaccinated. The World Health Organization recommends that people who are not fully vaccinated, have not previously been infected, are 60 years or older or have comorbidities such as heart disease, cancer and diabetes should postpone travel to areas with community transmission.Jessica Herzstein, a physician who advises organizations on how to manage the coronavirus and other health risks, including those associated with travel, said that she discourages anyone who is unvaccinated or immune-compromised from traveling. She also advises travelers going to destinations with a particularly high prevalence of cases to consider canceling. For those planning to travel, Dr. Herzstein strongly advises booster shots for those eligible and to take along a supply of at-home rapid antigen tests.David Freedman, the president-elect of the American Society of Tropical Medicine and Hygiene, said that the type of mask one wears while traveling is particularly important. Dr. Freedman discourages people from wearing cloth or homemade masks; N95 or KN95 masks are preferable, he said.It is difficult to assess how likely it is that a traveler will encounter an infected individual while flying to their destination. This is a particularly important to consider when traveling with children too young to be vaccinated or to wear a mask. Domestic flights in the United States do not require testing or proof of vaccination. Some countries and airlines require both. Others don’t.Creating a shorter window for testing — as the United States recently did for everyone flying into the country from abroad, regardless of nationality — makes sense, Dr. Freedman said. Testing three days before a flight can miss those who are incubating the virus and could be contagious and test positive by the time they board their plane. He said that a flight with a P.C.R. test requirement is also lower risk than a flight requiring an antigen test. But, he added, there is potentially more risk of transmission in airports than on planes, with their advanced air filtration systems. So much is out of even a meticulous planner’s control.Part of the challenge that many people are struggling with is how to weigh the other variables — like the mental health benefits of celebrating Christmas with family, or the professional benefits that might come from interacting with co-workers face-to-face. It’s easier for governmentsto define “essential travel” than for individuals, said Ms. Niebrzydowsk, the travel risk analyst.The Coronavirus Pandemic: Key Things to KnowCard 1 of 4The Omicron variant.