The duration of the disruption is unclear and will depend on how dangerous Omicron is and how resistant it is to vaccines, scientists and economists say.

Australia, Canada and the UK have sought to relax entry rules as companies demand workers to meet rising demand following the easing of Covid-19 restrictions, while the Germany is wondering if it should attract more immigrants.

In the Middle East, governments are loosening the rules that bind migrant workers to a single employer. Japan is also relaxing the restrictions.

Omicron disrupted some of those plans. On November 29, Australia postponed for two weeks plans to reopen its international border to skilled workers and fully vaccinated students. Japan has closed its border to non-resident aliens, although an immigration official said it was too early to say whether the variant would affect its broader goal of welcoming more foreigners.

Falling birth rates have left many wealthy countries with a shrinking working-age population, and the pandemic has exposed their growing dependence on foreign labor.

The Organization for Economic Co-operation and Development said the number of migrants arriving in its 38 member countries fell by nearly a third in 2020 from 2019 to 3.7 million, the largest drop since the records began in 2003.

The United States issued approximately 164,000 immigrant visas in 2020, down 64% from 2019. Although higher this year, the numbers are 21% lower than in 2019.

The number of new permanent residents fell by about half in Canada last year.

An expected rebound in migration this year and next is now overshadowed by Omicron. Labor migration from several large Asian countries, which provide a significant share of the world’s foreign workers, is well below pre-pandemic levels.

As of September of this year, the Philippines has sent 539,000 workers overseas, which is expected to be higher than 2020, but far from the 2.2 million in 2019.

For Leah Santiago-Mandalano, a 39-year-old mother of two from the Philippines, a dealer job in Morocco ended when Covid-19 closed the casino in early 2020.

Since returning home to a suburb of Manila last September, Ms Santiago-Mandalano has sold beauty products but has struggled to support her family. She applied for international jobs, but says few are available as many casinos are still closed. “I’m quite frustrated, but what can I do? ” she said. “I have to fight to survive.

In Australia, Fitch Ratings predicts that potential gross domestic product will fall 2.1% per year in the coming years, due to slower growth in the working-age population. Singapore’s population had shrunk by nearly 5% to 5.5 million at the end of June compared to 2019.

Slowing migration has intensified labor shortages around the world. Government programs to prevent layoffs have also limited the workforce reshuffle between struggling and booming industries, while some workers who dropped out of the workforce during the pandemic have yet to return.

Recruitment firm ManpowerGroup surveyed 45,000 employers in 43 countries about their hiring plans for the fourth quarter and found that 69% of them were having difficulty filling their positions.

In Germany, businesses are struggling to fill more than a million vacant jobs, as a sharp drop in net immigration has exacerbated shortages resulting from a rapidly aging workforce. German officials say the country needs some 400,000 skilled foreign-born workers every year.

“No customer says they have the right number and quality of employees,” said Gunther Schmitz, bank manager for corporate clients outside of Frankfurt. “It’s amazing how it goes at all skill levels, from cleaning staff to engineers. “

Germany’s new government plans to streamline immigration rules to attract skilled workers from abroad.

The Government of Canada plans to admit a record 401,000 new permanent residents this year, about 60,000 more than before the pandemic, and plans to increase that number over the next two years.

“Canada needs immigration to create jobs and drive our economic recovery,” Immigration Minister Sean Fraser said in a recent emailed message to the Wall Street Journal.

In Japan, where the working-age population has been declining since 1995, the pandemic has overturned plans to attract more foreign workers to labor-scarce sectors such as elderly care and construction. by freeing migrants from strict rules prohibiting new arrivals from bringing their families or extending their stay.

In 2019, the country set a goal of bringing in 345,000 foreign workers over the next five years. But so far only 40,000 have arrived. As labor shortages spread to sectors such as agriculture and food manufacturing, the government is considering relaxing the rules more broadly.

In the UK, pandemic worker shortages were magnified by Brexit, which ended the automatic right of citizens of European Union countries to live and work in the country.

The number of EU nationals residing in the UK fell by 217,000 in 2020 compared to 2019, to 3.5 million, according to official estimates. Job vacancies peaked at 1.2 million this fall.

Earlier this year, officials tightened immigration rules, including looking at potential arrivals based on expected earnings and fluency in English. But they are now issuing thousands of additional visas to quickly fill labor shortages, including 5,000 three-month visas for foreign truck drivers and 5,500 for the food industry to ensure a sufficient number. poultry houses be available to process Christmas turkeys.

Afia Akram has struggled to find staff to expand her samosa-making business in Birmingham, England, as the supply of workers she normally hires in Central and Eastern Europe has dried up. She hasn’t been able to find native-born workers comparable to wages she can afford.

“Covid has masked the problem with Brexit,” which was already shrinking foreign labor, she said.

In the United States, where a record 11 million jobs were vacant in October, finding a political solution to the migrant labor shortage has been more difficult.

A policy change in 2016 made it more difficult for companies to get workers back to the country on H-2B visas, designed for temporary non-farm workers.

Judith Ogden, owner of Ogden’s Design and Plantings Inc., a home landscaping company in St. James, NY, used to bring in the same workers from overseas year after year. Now she has to participate in a government lottery to get visas for them. She only got the workers she was looking for this year in July, three months after she needed them.

“I’ve lost clients because people don’t have the patience to wait, it’s horrible, horrible,” she said. “The sad thing is if I had my employees my business would grow exponentially. “

Ms. Ogden tried to find premises to fill the positions. She even asked her congressman to put a sign in her office. She offered about $ 18 an hour, plus overtime. Nobody took a job.

Congress has raised the H-2B visa cap this year, to a total of 66,000 for fiscal 2022, but that remains well below demand. The number of H-1B visas is also falling behind demand, but there is little movement for a large-scale immigration overhaul in Congress.

—Kim Mackrael, Miho Inada, Alice Uribe, and Tom Fairless contributed to this article.

Write to Jason Douglas at [email protected], Ian Lovett at [email protected] and Jon Emont at [email protected]