Diphtheria, tetanus, and pertussis vaccine. A comparison of the immune response and adverse reactions to conventional and acellular pertussis components
K. M. Edwards, E. Lawrence and P. F. Wright
Although the conventional Bordetella pertussis vaccine, which consists of
killed whole organisms, has been shown to be effective in preventing
disease, it has been associated with transient local and systemic reactions
and may produce encephalopathy, though rarely. A new acellular pertussis
vaccine containing partially purified protein antigens, filamentous
hemagglutinin, and lymphocytosis-promoting factor hemagglutinin has been
developed for use in Japan. We compared the immunogenicity and
reactogenicity of conventional and acellular pertussis vaccine. Forty
children aged 4 to 6 years and 40 children aged 18 to 24 months, all
previously immunized at appropriate times with conventional diphtheria and
tetanus toxoids and pertussis vaccine, were enrolled. We randomly assigned
children to receive either conventional pertussis vaccine or acellular
pertussis vaccine in a double-blind fashion. The diphtheria and tetanus
components in both preparations were identical. Equivalent rises in
pertussis agglutinin titers and antibodies to filamentous hemagglutinin and
lymphocytosis-promoting factor hemagglutinin were measured in both vaccine
groups at both ages that we studied. However, reaction rates to the two
vaccines in both age groups were strikingly different. Acellular pertussis
vaccine was significantly less reactogenic for fever, pain, fretfulness,
abnormal gait, and local reactions at the vaccine administration site. If
studies in progressively younger children confirm its reduced
reactogenicity and equal immunogenicity, and if large-scale trials indicate
its efficacy, the acellular pertussis vaccine may be a more appropriate
candidate than the current vaccine.
