In the pre-
vaccine era, there was little information about clinical
pertussis in adults, although deaths were noted. Today Bordetella pertussis
infection in adults is noted to cause a full spectrum of clinical manifestations. If single serum serologic diagnosis becomes routine, the finding of adult cases would increase dramatically. Reported adult
pertussis was rare in the pre-
vaccine era and it has been increasing markedly in the present era. In the present
vaccine era, data on adult
pertussis and B.
pertussis infection have been gathered by studying prolonged
cough illnesses, serologic studies determining recent
infections and prospective rate of illness studies. These studies suggest that approximately 15% of prolonged
cough illnesses are due to B.
pertussis infections; the yearly rate of
infection is approximately 6% and the yearly rate of B.
pertussis infection with clinical manifestations is >500/100,000. The duration of protection following natural
infection or vaccination is relatively short. Therefore, unless new and better
pertussis vaccines are developed, lifelong
vaccine-induced immunity is not possible.