One hundred American Airlines flight attendants have tested positive for coronavirus, according to their union, the Association of Professional Flight Attendants.
The union says the airline has agreed to start providing face masks for frontline team members.
More than 27,000 union members will have the option to wear a mask while working.
The masks are planned to be distributed this week, officials said.
American Airlines refused to comment on how many employees had tested positive for COVID-19.
The union says only about one in four of its flight attendants will be flying in May, due to major cuts in the airline's schedule.