tor responderet på kighostekomponenten i vaccinen, hvilket var defineret som forekomsten af antistoffer hos initialt seronegative individer (dvs. individer med præ- vaccinationstitre < 15 ELU/ ml) eller en
ge component of the vaccine, which was defined as the appearance of antibodies in initially seronegative subjects (i. e. subjects with pre-vaccination titres < 15 ELU/ ml) or a post-vaccination titre at least equal to pre-vaccination levels in subjects initially seropositive due to maternally- lon derived antibodies.