The bat in question flew into the cabin of a Delta Airlines flight from Madison, Wisconsin, to Atlanta that had 50 passengers and three crew members aboard, the Centers for Disease Control and Prevention said in report.

When the bat flew into the airplane lavatory, a passenger closed the door, trapping it, CDC veterinarian Danielle Buttke told Reuters. The pilots then returned to Madison and passengers disembarked.

Maintenance crew members tried to capture the bat so it could be tested for rabies, but it flew out of the lavatory when the door was opened and then out the airplane's cabin door. It eventually left the airport terminal through automatic doors, Buttke said.

Because the bat had not been tested for rabies, the CDC interviewed 45 of the passengers and all three crew members. None had any physical contact with the bat or exposure to its saliva, the CDC said. Five passengers were never located for interviews.

"I would say there is no evidence (of rabies exposure)," Buttke said. But he added, "I don't think we can be certain."

She said that most of the passengers were "very good natured" about the incident.

"As a whole, I was very impressed with everyone's behavior and how calm they were," Buttke said, saying the flight's delay and possibly missed connections might have caused more passenger ire.

In 2010, about 6 percent of bats captured for testing were infected with rabies, the CDC said. A bat seen active during daylight or in an area bats are not normally found, such as an aircraft cabin, should be tested for rabies as a precaution.

(Editing By Cynthia Johnston and Philip Barbara)

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