Japan's experience in pertussis epidemiology and vaccination in the past thirty years.

The experience in Japan that pertussis was controlled by the nation-wide regular vaccination and that the reincrease of case notification occurred recently after the decrease of vaccine acceptance rate upholds the view that pertussis vaccine produced under the national control system is fully protective. Though the recent decrease of the vaccine acceptance rate was due to the public reaction to rather imbalaanced arguments concerning the vaccine risk, it is also true that a more potent and less toxic component vaccine is urgently needed at this moment.