Swine Flu Carrying Littrell -- Airborne Toxic Event

Pigs don't fly -- but yesterday one Backstreet Boy just infected with the swine flu did.

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After being quarantined in his NY hotel with the virus since Sunday, Brian Littrell finally got the A.O.K. to travel back to L.A. -- and though he said his doc cleared him for human interaction, our pap wasn't taking him up on any proposed mouth-to-mouth contact.