Dr. Gupta -- You Give Me Fever

Our cameraman lathered on the hand sanitizer before talking to former swine flu patient Dr. Sanjay Gupta -- but according to the good doc, pouring on the Purell wouldn't totally keep the pig virus at bay anyway.

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In Malibu last night, Gupta gave us the 411 on H1N1 and celeb infectee Brian Littrell, saying dude probably wasn't contagious yesterday when he flew in from NY -- because the Backstreet Boy told The Gup his fever has passed when he went airborne.

FYI -- our photog who shot Littrell at LAX is now sick with flu-like symptoms. No word on how the guy who shot this footage is feeling ... yet.