How could she be allowed to board an airplane after treating a patient who just died of Ebola?

Update:

Statement from Frontier Airlines:

“At approximately 1:00 a.m. MT on October 15, Frontier was notified by the CDC that a customer traveling on Frontier Airlines flight 1143 Cleveland to Dallas/Fort Worth on Oct. 13 has since tested positive for the Ebola virus. The flight landed in Dallas/Fort Worth at 8:16 p.m. local and remained overnight at the airport having completed its flying for the day at which point the aircraft received a thorough cleaning per our normal procedures which is consistent with CDC guidelines prior to returning to service the next day. It was also cleaned again in Cleveland last night. Previously the customer had traveled from Dallas Fort Worth to Cleveland on Frontier flight 1142 on October 10.