title: Pertussis cases in Pennsylvania on increase.
mesh_terms: D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D010414:Pennsylvania; D010567:Pertussis Vaccine; D014917:Whooping Cough / Q000453:epidemiology* / Q000517:prevention & control
chemical_list: D010567:Pertussis Vaccine