Immunologic and Epidemiologic Experience of Vaccination With a Monocomponent Pertussis Toxoid Vaccine

Abstract

ABSTRACT. Pertussis re-emerged in Sweden with a cumulative incidence of about 60% during the first 10 years of life, when the locally produced cellular vaccine lost its efficacy around 1970 and general vaccination was discontinued in 1979. The epidemiology, clinical features, and immunology of pertussis and a monocomponent pertussis toxoid vaccine were studied in Gö teborg, Sweden.After phase 1 and 2 studies, a randomized, doubleblind, placebo-controlled trial of pertussis toxoid (PTox), compounded with diphtheria and tetanus toxoids, was administered to 3450 children according to the Swedish schedule at 3, 5, and 12 months of age. After a mean follow-up of 18 months, the efficacy was 71% overall and 75% in household contacts, respectively. A statistically significant correlation was found between the level of PTox-induced antibodies and protection against pertussis. As observed with cellular and with multicomponent acellular vaccines, PTox reduced the severity of disease and the percent of children with positive cultures. Furthermore, vaccination reduced the transmission of Bordetella pertussis to household contacts in the vaccinees compared with the controls who received only diphtheria and tetanus toxoids. Patients with culture-verified Bordetella parapertussis infection reacted with antibodies to pertactin and to filamentous hemagglutinin but not to pertussis toxin, and some subsequently developed pertussis. The antibody responses of patients with pertussis to the surface polysaccharides of B pertussis and to B parapertussis were cross-reactive serologically. Serosurveys showed that only antibodies to pertussis toxin were related to the occurrence of pertussis in the general population: antibodies to filamentous hemagglutinin and pertactin were probably stimulated by antigens of other bacteria as well as Bordetellae.Mass vaccination of Gö teborg children born in the 1990s was started in 1995. In February 1999, about 55% had been vaccinated and both B pertussis and pertussis decreased significantly in individuals of all ages (herd immunity). Similar to diphtheria, PTox-induced immunity to pertussis occurs both on an individual and community basis.The apparent greater efficacy of multicomponent acellular pertussis vaccines compared with monocomponent PTox was proposed to be an artifact created when the diagnosis of pertussis was made by the serologic criteria of the World Health Organization only. Our conclusion is that PTox is both an essential and alone sufficient antigen in acellular pertussis vaccines. Pediatrics 2001; 108(6). URL: http://www.pediatrics.org/cgi/content/full/ 108/6/e115; pertussis, pertussis toxoid, vaccine.

Pertussis toxin inhibits neutrophil recruitment to delay antibody-mediated clearance of Bordetella pertussis

“…Other studies have recognized that PTx is one of the critical components necessary for higher efficacy of acellular pertussis vaccines (34,60). Although antibody titer to pertactin positively correlates with the resistance to diagnosed disease symptoms, addition of pertactin or filamentous hemagglutinin to PTx increases the efficacy of acellular pertussis vaccines (15,33).…”

Pertussis: increasing disease as a consequence of reducing transmission

“…Estimates for individual efficacy of pertussis vaccines are around 70-80% and induced protection is of limited duration. [3][4][5] Despite high vaccination coverage, B pertussis remains endemic and reports of increasing incidence in the USA, 6 Canada, 7 the Netherlands, 8 Australia, 9 France, 10 the UK, 11 and Poland have been accumulating since the 1980s. 12 This increase has been accompanied by a shift to older age groups, [13][14][15] raising concerns about household transmission to vulnerable infants 16,17 and calling for a reappraisal of clinical management in adolescents and adults 18,19 and a reinforcement of vaccination strategies.…”

Cost-effectiveness of pertussis booster vaccination in the Netherlands

“…Although, the exact duration of this immunity against transmission is not known, there is evidence that vaccinations do induce herd protection. For example, in Sweden after the re-introduction of the pertussis vaccine in 1995 after 16 years, a significant reduction in the number of isolates in unvaccinated infants was noticed [17]. Also, several other observational studies [17][18][19] have demonstrated a decrease in B. pertussis incidence rates in unvaccinated subgroups (when the vaccination uptake was higher than 80%).…”

“…For example, in Sweden after the re-introduction of the pertussis vaccine in 1995 after 16 years, a significant reduction in the number of isolates in unvaccinated infants was noticed [17]. Also, several other observational studies [17][18][19] have demonstrated a decrease in B. pertussis incidence rates in unvaccinated subgroups (when the vaccination uptake was higher than 80%). Furthermore, a decrease in the transmission of B. pertussis infection from vaccinated through household contacts was observed in several vaccine efficacy studies [20][21][22][23].…”