DALLAS (AP) — Southwest Airlines has become the latest U.S. airline to say that it will require its employees to be vaccinated against COVID-19. The Dallas-based company said its workers must be fully vaccinated by Dec. 8 in order to continue working at the airline. Employees can seek approval to skip the shots due to medical or religious reasons. Southwest said it has to mandate vaccines because of new rules from the Biden administration that companies with federal contracts must have a vaccinated staff. Southwest’s work for the government includes flying the military in emergencies and carrying mail for the U.S. Postal Service. Southwest has 54,000 employees.