Delta Air Lines on Thursday said it will begin testing employees for COVID-19 and its antibodies, starting at its hub at Minneapolis-St. Paul International Airport.

The airline, which is the dominant carrier at MSP, is working with Mayo Clinic and Quest Diagnostics Inc. on the testing regime. The tests are part of a bigger effort to keep its people, planes and facilities free of the virus.

In a memo to employees Thursday, Delta Chief Executive Ed Bastian said the testing will begin at MSP next week, then roll out to Atlanta, where the company is based, Detroit and New York, cities where it also operates hubs.

Through May, the rate of COVID-19 infection among Delta’s employees who deal with the public has been five times lower than the national average, he said.

Delta also has started an internal unit called the Global Cleanliness team, which will be responsible for new “standards and policies to ensure a consistently safe and sanitized customer and employee experience,” Bastian said in the memo.

Such measures are also designed to encourage the flying public to return. But at the same time, Delta is taking steps that show it expects air travel to be diminished for some time to come.

This week, it offered incentive packages — including cash, health benefits, travel passes and career services — to encourage employees to leave the airline for good.

Delta, which employs about 9,000 people in the Twin Cities and a few hundred more elsewhere in the state, has not said precisely how many of its 90,000 employees it aims to trim with the incentives.

Bastian said executives hoped the incentives — which he described as a “once-in-a-career” offer in cash and retiree benefits — would appeal to enough people that Delta would not have to resort to involuntary furloughs.

“The last thing we expected this year was to be encouraging people to depart — 2020 was intended to be a year of growth,” Bastian wrote. “But it’s clear that the impact of the pandemic will be lengthy, and that Delta will need to be a smaller airline over the next few years.”

Since the coronavirus outbreak began to constrain air travel, Delta has reduced its flight schedule by more than 80% and parked more than two-thirds of its 900 planes. It also announced the early retirement of its MD-88, MD-90 and Boeing 777 aircraft, or 94 planes in all.

Analysts estimate that Delta has reduced its daily cash burn rate to about $40 million from $50 million in early May. Even so, the airline also has announced that it will need to renegotiate its debt agreements to avoid a default next year.

Separately, Bastian told employees that Delta has joined other businesses in Minnesota by calling for state lawmakers to pass a police reform bill “focused on preventing unacceptable police behavior and ensuring that perpetrators of racist actions are held accountable.”

Delta is also pressing lawmakers in its home state of Georgia to pass hate-crimes legislation. The state is one of five in the country without a law offering extra protection against hate crimes.

And Bastian’s note said the company itself “must remain safe and welcoming for all Delta people” even beyond its airports and planes.

“We will not tolerate racist, bigoted or hateful acts or statements in our workspaces or directed at our people,” Bastian said. “This includes racial and other bigoted, hateful and offensive comments on social media by Delta people, which hurts our culture and our people.”