When I was 16 I found out that somewhere along the line, my vaccinations I'd gotten when younger had a weak dose of the pertussis vaccine. A few people in my age group ended up getting it, including me.
For parents who are considering not vaccinating their kids: Get them vaccinated, you stupid fucks. Whooping cough fucking sucks. I coughed HARD for 3 months straight and was unable to breathe for several seconds after a coughing fit. That could get scary. I actually coughed so hard that I ended up breaking a rib. If that bitch Jenny McCarthy had been around at the time I would have pulled my rib right out of my side and stabbed her to death with the broken end.