When you're in the womb, you're in a sterile environment. When you enter the birth canal and the world, you're not. Very quickly, you have, living on the surface of your body, trillions of bacteria, literally trillion.
Paul A. OffitPhysicians who care for adults generally don't think about vaccines as much as pediatricians do, and adults think of vaccines as a kid thing.
Paul A. OffitIf you've had a cough that lasted weeks, a cough that just doesn't seem to go away, chances are it was pertussis.
Paul A. Offit