If a teenager contracts Pertussis, does this mean they were not properly immunized?
Not necessarily. Vaccine-induced immunity to Pertussis is believed to persist for about 10 years following the last dose. So even if a child receives all 5 doses of Pertussis vaccine on schedule, he or she may still be susceptible as a teenager. The need for “booster” doses of Pertussis vaccine for adolescents or adults is currently being studied.
