(Reuters) – Amazon.com Inc on Thursday informed staff at its U.S. warehouses and logistics sites that they must report being fully vaccinated by March 18 if they wish to receive paid leave due to COVID-19.

The company also said fully vaccinated operations staff could work without a face covering starting on Friday as local regulations allow, according to a message to workers that Amazon shared with Reuters.

The online retailer attributed its policy updates to a recent decline in coronavirus cases across the United States, increasing rates of vaccination, and guidance from its medical experts and public health authorities.

“This is a positive sign we can return to the path to normal operations,” the company’s message said.

Amazon’s COVID-19 protocols have faced scrutiny throughout the pandemic, as safety measures taken by the company have been met with criticism by some workers that it was not doing enough to protect them.

The company’s status as America’s second-biggest private employer, behind Walmart, has added significance to its policies. Amazon had a full and part-time headcount greater than 1.6 million worldwide as of Dec. 31.

The retailer’s paid leave change does not regard workers who have received a religious or medical accommodation, its message said. Unvaccinated employees without such accommodation can take unpaid time off for a week of COVID isolation, it said.

(Reporting by Jeffrey Dastin in Palo Alto, California; Editing by Chris Reese, Diane Craft and Sandra Maler)