TOKYO -- Compared with the United States and Europe, countries in East Asia have been held up as success stories in the battle against the coronavirus pandemic.
But in Japan, South Korea and Hong Kong, governments are reimposing restrictions this week, as public complacency, policy blunders and colder weather fuel a new surge in virus cases.
Japan is scaling back a contentious subsidy program designed to encourage domestic tourism and dining out, after it became clear the enticements were helping to fuel a third wave that has resulted in record new infections.
In Seoul, officials ordered bars and nightclubs to close and limited dine-in service at cafes and restaurants this week, after an earlier easing of restrictions allowed the virus to roar back.
Hong Kong also closed bars and nightclubs, days after officials postponed the launch of a travel bubble with Singapore -- a highly anticipated experiment that was set to herald a reopening of quarantine-free travel in Asia -- after the virus found gaps in the territory's defenses to stage a comeback.
The numbers of new infections there are a fraction of those in the West, with Japan recently reporting more than 2,000 new cases a day, South Korea more than 300 a day, and Hong Kong recording 73 new confirmed cases Monday -- compared with more than 150,000 a day in the United States.
Yet the infection rates are still high enough to ring alarm bells, especially given the high proportion of elderly people in places like Japan, as winter approaches, and doors and windows close against the chill.
Pandemic fatigue is a key ingredient, experts say. After many months of restrictions and with cases seemingly under control for a while, people have become tired of the rules, bored with staying at home and complacent about the risks.
"Our control measures rely on voluntary behavior change," said Hitoshi Oshitani, a professor at Tohoku University's Graduate School of Medicine who is a member of the government's coronavirus advisory team. "And it's getting more difficult to persuade people to change behavior. Even though the number of cases is much, much higher than in March or April, people are quite relaxed."
Kang Do-tae, South Korea's vice health minister, warned Tuesday of a "triple bind" of asymptomatic patients, transmission among young people, and colder weather in which the virus thrives because of increased indoor activity.
"The unforeseen development of the third wave forewarns an even harsher and harder winter," Kang said at a meeting.
Tokyo Gov. Yuriko Koike also raised concerns Tuesday.
"It is clear that the movement of people is having an impact on this increase in cases," she said at a news conference. "And we are seeing these situations where in times of eating out, the virus does spread. This is then brought home into the household, where perhaps there are elderly members of the family who have lower immunity."
In South Korea, which won praise for effectively tamping down the first major epidemic outside China, officials have continued to fight small but persistent outbreaks.
Believing it had a second wave under control, the government eased social distancing rules last month. Over the past two weeks, however, more than 60 infection clusters emerged across the country, including at schools, military bases and churches.
"Infections from the first and second waves left lingering transmission risks across the South Korean society, which caught fire as social distancing rules were lifted without proper preparations," said Kim Yoon, a professor at Seoul National University's College of Medicine, warning the outbreaks could overwhelm South Korea's contact-tracing regime.
"Unlike previous outbreaks which stemmed from few big clusters, the third wave consists of dozens of small clusters that are harder for contact tracers to track," he added.
In the United Kingdom, British authorities gave the green light Tuesday to holiday reunions, relaxing restrictions on social mixing over Christmas and offering arriving international travelers a way to cut short quarantine if they test negative for covid-19.
The U.K. government and administrations in Scotland, Wales and Northern Ireland struck a deal that will ease limits on travel and socializing over the festive period so that friends and families can get together.
Over the five days between Dec. 23 and 27, up to three households can form a "Christmas bubble," and members can move freely between them. Those traveling to and from Northern Ireland will be permitted to travel for an additional day either side.
People are currently barred from visiting members of other households in much of the U.K., and there are limits on travel to high-infection areas.
Cabinet minister Michael Gove said the agreement "will offer hope for families and friends who have made many sacrifices over this difficult year."
Information for this article was contributed by Simon Denyer, Akiko Kashwagi, Min Joo Kim, Theodora Yu and Shibani Mahtani of The Washington Post; and by Pan Pylas and Jill Lawless of The Associated Press.