By Josh Mitchell

A rise in coronavirus infections is threatening to further slow the U.S. jobs recovery, which has lost momentum in recent months.

The number of Americans who filed initial jobless claims, a proxy for layoffs, fell earlier this month to the lowest level since March, when the pandemic shut down much of the country's business activity. Economists expect a report out Thursday from the Labor Department to show claims fell slightly last week. That's the good news.

The bad news: Claims remain exceptionally high by historical standards, and the decline has been slowing. Two weeks ago, 787,000 Americans filed initial claims, more than twice the weekly average in early March. Anecdotal evidence -- companies big and small announcing plans to lay off more workers as the pandemic persists -- suggests the labor market recovery will be protracted.

More than half the economists responding to a Wall Street Journal survey this month said they didn't expect the country to claw back until 2023 or later all the jobs lost as a result of coronavirus-related shutdowns.

The biggest threat right now is a rise in infections. The average number of new coronavirus cases reported daily over the past week reached a new peak of 68,767 on Monday. States and cities could impose new restrictions on businesses in response, as European countries have done. Consumers could also hunker down again, cutting back on travel, eating out and shopping.

"The easy gains have been had so far," said Brett Ryan, senior U.S. economist at Deutsche Bank. "We don't think that you're going to see the draconian shutdowns that you had at the beginning of the pandemic. It's going to be much more localized, but that alone keeps firms cautious."

Employers have been increasing their payrolls for months after severe staffing cuts in the spring. They shed 22.2 million jobs in March and April, during the worst of the shutdowns, and have added 11.4 million since then as restrictions eased.

But the monthly job gains have slowed since June. Employers added 661,000 jobs in September, less than half the 1.5 million added in August. The unemployment rate -- 7.9% in September -- remains more than twice as high as in February, when it tied a 50-year low of 3.5%.

The strong job growth over the summer largely reflected businesses such as restaurants and hospitals staffing back up quickly after being shut down for weeks.

Many businesses continue to operate below capacity. Many restaurants, for example, have been serving diners only outside or at half-capacity indoors to space out tables to comply with social-distancing rules.

The labor market faces at least two other threats. One is cold weather. Businesses moving indoors during the winter could risk further spread of the virus, which could prompt additional shutdowns.

The second is the expiration of enhanced unemployment benefits that the Trump administration had put in place this summer to boost the amount workers receive for unemployment compensation. When those run out, consumers might cut spending, which could prompt businesses to lay off workers.

Failed efforts by Congress and the White House to pass a new federal relief package "will likely result in more small business closures and state and local layoffs in the fourth quarter," David Kelly, chief global strategist of JPMorgan Funds, said in a note to clients this week.

"Most important, there continue to be wide swaths of the U.S. economy which simply cannot get back to normal in a worsening pandemic," Mr. Kelly said, "including travel, leisure, entertainment, restaurants and bricks-and-mortar retailing."

Write to Josh Mitchell at joshua.mitchell@wsj.com

(END) Dow Jones Newswires

10-29-20 0544ET