Pertussis Antibodies in the Sera of Children after Acellular Pertussis Vaccination

ABSTRACT

PURPOSE: The pertussis vaccines are divided into whole-cell vaccine and acellular vaccine. Purified component acellular pertussis vaccine, originally developed in Japan, has been used for primary immunization series in Korea since 1984. We performed this study to evaluate the prevalence of pertussis antibodies following vaccination with acellular pertussis vaccine. METHODS: We randomized 80 children who were immunized according to vaccine schedules including less than 2 month-old infants at Department of Pediatrics, Catholic University Medical College from February 1995 to October 1995. We measured agglutination titers of children by bacterial agglutination test. RESULTS: 1) The age distribution ranged from 5 days to 7 years old, the mean age was 14.5+/- 12.8 months and male to female ratio was 11. 2) Only 23 cases (28.8%) of the 80 cases were positive results. 3) Among 7 infants who were less than 2 months-old and were not immunized, 5 infants (71.4%) were seropositive. 4) There was no significant difference in positive rates among age groups which include 2 to 6 months age group, 7 to 18 months age group, and older than 18 months age group. CONCLUSIONS: The prevalence of pertussis positive rates is only 28.8% and there was no difference among age groups.