Every year in the U.S. about 20 to 25 children die from pertussis, most are young babies who have not been fully immunized. There are several things that you can do to help protect your baby from pertussis. Babies get a vaccine to protect them from pertussis when they are 2 months, 4 months, and 6 months of age. They get an additional dose at 15 to 18 months.