(AP) -- Health officials say a bat on a flight from Wisconsin to Atlanta last week has sparked a national search for passengers to protect them against possible rabies.

Officials don't know if the bat had rabies. It escaped. But they want to alert passengers of the risk just in case. The Centers for Disease Control and Prevention says it is trying to reach all 50 people who flew on Delta flight 5121, which departed from Madison, Wis., to Atlanta at 6:45 a.m. on Aug. 5.

If the animal was rabid, people could catch rabies from a bite or exposure to the bat's saliva.

CDC officials asked anyone on the flight to call 1-866-613-2683. The airline didn't retain the records for all the passengers.

The jet was in the air when the winged animal emerged and a passenger shot a video. Operators of the flight said it could have been a bird. But CDC says its rabies expert believes from the video that it was a bat.

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