Protective efficacy of the Takeda acellular pertussis vaccine combined with diphtheria and tetanus toxoids following household exposure of Japanese children
E. A. Mortimer Jr, M. Kimura, J. D. Cherry, H. Kuno-Sakai, M. G. Stout, C. L. Dekker, R. Hayashi, Y. Miyamoto, J. V. Scott, T. Aoyama and al. et
Department of Epidemiology, Case Western Reserve University, Cleveland, Ohio.
The clinical efficacy of an acellular pertussis vaccine containing
lymphocytosis-promoting factor, filamentous hemagglutinin, agglutinogens,
and the 69-kd outer membrane protein, combined with diphtheria and tetanus
toxoids and adsorbed onto an aluminum salt, was assessed in a household
contact study. The occurrence of pertussis 7 to 30 days following home
exposure among 62 previously vaccinated children was compared with that
among 62 unvaccinated children similarly exposed. Classic whooping cough
was diagnosed in 43 unimmunized children, and 1 vaccinated child
experienced a 5-week illness that was probably pertussis (efficacy, 98%;
95% confidence interval, 84% to 99%). A few children in each group incurred
respiratory illnesses that may have represented mild, atypical pertussis;
including these as probable pertussis, vaccine efficacy was 81% (95%
confidence interval, 64% to 90%). It is concluded that prior immunization
with this four-component pertussis vaccine combined with diphtheria and
tetanus toxoids is highly efficacious in preventing pertussis.
