(Reuters) - American Airlines has told pilots they should take a COVID-19 vaccine on their own time while preparing a broader voluntary program for employee vaccinations at airports around the country. Vaccines could be ready for Chicago-based staff as soon as mid-February, though American is not requiring them, said Jennifer Saddy, managing director of absence management who is part of the team leading American’s vaccine efforts. A memo to American’s pilots called the decision to take the vaccines “personal.” “As such, if you elect to take the vaccine you should schedule it on your days off and so that it does not impact your ability to be in place and operate your scheduled flying given the 48-hour requirement,” American’s managing director of line operations, Chip Long, and managing director of flight operations, John Dudley, said in the memo, reviewed by Reuters. The Federal Aviation Administration has said pilots and controllers must not fly or conduct safety-related duties for 48 hours after receiving a COVID-19 vaccine. Asked about the memo, American Airlines said it is working on plans to provide the vaccine to pilots and other employees as it becomes available in different states but does not plan to require them unless they are mandated by certain countries for entry. The Allied Pilots Association representing American’s pilots did not immediately comment. A spokesman for the union representing its flight attendants said it expects direction from the company about vaccines next week. Private U.S. companies have the right under the law to require employees to get vaccinated against COVID-19, but are unlikely to do so because of the risks of legal and cultural backlash, experts have said. Inoculation against the disease caused by the coronavirus is considered key to safely reopening large parts of the U.S. economy. Some companies are offering incentives to workers to get a vaccine when it is available. Retailer Dollar General Corp , for example, is offering frontline workers a bonus worth four hours of pay. Air travel has been particularly hard hit by the pandemic. Delta Air Lines has not decided whether to require the vaccine for its employees. “That’s going to be more of a government discussion with the regulatory authorities than an individual airline’s decision,” Chief Executive Ed Bastian told Reuters. United Airlines said its vaccine plans are still a work in progress. Strict rules putting healthcare workers first in line have slowed the rollout in the United States, which varies by state. The United States on Tuesday expanded COVID-19 testing requirements for nearly all people entering the country from abroad, including citizens, but does not require tests for domestic flights and has not issued guidance on vaccines for travel. American is still working out details for its vaccine plans but will likely offer shots to employees by appointment or on a walk-in basis at its medical clinics at airport hubs, in partnership with its health provider Premise, Saddy said. JetBlue Airways, based in New York which is now offering the vaccine to airline employees, said some of its workers were receiving it.