Avoid touching the three grimiest surfaces found on planes and in airports

If you'll be among the 24 million people expected to be in an airport and on a plane this Thanksgiving holiday period, Charles Gerba, the University of Arizona microbiology professor known as "Dr. Germ," has some important travel advice for you: Pack light and carry hand sanitizer.

Gerba, whose travel souvenirs often include test swabs from airplane lavatories, has identified the three germiest spots on airplanes -- toilets, tray tables and the latches on overhead bins.

He's found the norovirus, the influenza virus, diarrhea and MRSA on airplane tray tables, which he says are rarely disinfected. The latches on overhead bins also get "lots of touching, but no cleaning."