von Linstow, Marie-Louise5; Pontoppidan, Peter Lotko3; von König, Carl-Heinz Wirsing3; Cherry, James D3; Høgh, Birthe6
1 Graduate School of Health and Medical Sciences, Faculty of Health and Medical Sciences, Københavns Universitet2 Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet3 unknown4 Dean´s office, Faculty Service, Faculty of Health and Medical Sciences, Københavns Universitet5 Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet6 Dean´s office, Faculty Service, Faculty of Health and Medical Sciences, Københavns Universitet
We measured IgA and IgG antibodies to pertussis toxin (PT) and filamentous hemagglutinin (FHA) in sera from 203 1-year-old children who had received one to three doses of a monocomponent PT toxoid vaccine. Ten children (5%) had IgA antibody to PT indicating recent infection; seven of these children had received three doses of vaccine. PT IgA responders did not have significantly longer coughing episodes than PT IgA non-responders. Since an IgA antibody response occurs in only approximately 50% of infected children, the actual infection rate in our cohort is estimated to approximately 10%. The apparent high Bordetella pertussis infection rate in Danish infants suggests that the monocomponent PT toxoid vaccine used in Denmark has limited efficacy against B. pertussis infection. A prospective immunization study comparing a multi-component vaccine with the present monocomponent PT toxoid vaccine should be undertaken.
European Journal of Pediatrics, 2010, Vol 169, Issue 9, p. 1119-22