McDonald’s Corp will inspect all its U.S. restaurants to ensure compliance with safety standards as coronavirus cases surge again and “COVID fatigue” sets in, according to an internal note seen by Reuters on Friday.

“It is apparent we are entering what many predicted would be the most difficult period of the pandemic,” said the note, from McDonald’s Chief Field Officer Charlie Strong and two U.S. franchisees who lead internal relations with the corporation.

The so-called “safety reaffirmation visits” were developed jointly with franchisees, the note said, and should be concluded by Dec. 31. The company may conduct follow-up visits where necessary.

Company-owned stores will also be examined, McDonald’s said.

The pandemic prompted widespread changes in how restaurants conduct business, with many relying more on drive-thru, carry-out and delivery.

U.S. sales at most restaurants plunged in April as coronavirus restrictions became widespread. Most big chains, including McDonald’s, have seen steady recovery since then.

McDonald’s owners were also urged in the note to ensure that drive-thrus contain equipment that allows customers to use credit cards without having to hand them to cashiers, and that staff inside are separated by protective panels when social distancing is not possible.

In a separate blog post on Friday, McDonald’s USA President Joe Erlinger said the burger chain would soon convene industry roundtables to share key lessons learned.

“McDonald’s success – just like the success of Walmart, Apple, Starbucks, or any other U.S.-based business – depends on all of us getting back to some version of normal as quickly as possible,” he wrote.