RT Journal Article SR Electronic T1 In Reply: Pertussis Immunization JF Pediatrics JO Pediatrics FD American Academy of Pediatrics SP 638 OP 639 VO 83 IS 4 A1 CHERRY, JAMES D. YR 1989 UL http://pediatrics.aappublications.org/content/83/4/638.2.abstract AB Dr Emerson suggested that the report ignored the distinction between infection and illness when we suggested that adult booster doses would reduce transmission of Bordetella pertussis in adults and could help in the eradication of pertussis in our population. In supporting his suggestion, Dr Emerson has underestimated the number of pertussis cases presently occurring in adults in the United States, has used an unimpressive reference to indicate that adult doses of tetanus and diphtheria toxoids are unnecessary, and has inappropriately questioned the herd immunity concept (the immunization of children at school entry and of adults) in the protection of young children from pertussis.