Scientists debate why the number of whooping cough cases is up, and whether the effectiveness of a vaccine introduced within the last two decades is to blame.
Questions Raised About Pertussis Reemergence
Questions Raised About Pertussis Reemergence
Scientists debate why the number of whooping cough cases is up, and whether the effectiveness of a vaccine introduced within the last two decades is to blame.
Scientists debate why the number of whooping cough cases is up, and whether the effectiveness of a vaccine introduced within the last two decades is to blame.
Herd immunity, or the protection of individuals who are not vaccinated due to generally high vaccination rates within a population, does not currently exist in many pockets of the US.