Seroprevalence of pertussis antibodies in 6-17-year-old students in Ahvaz, south-west Islamic Republic of Iran

Although pertussis is a vaccine-preventable infection, vaccine-induced immunity is not lifelong and booster doses are recommended according to national disease epidemiology. The aim of this study was to evaluate pertussis-IgG levels in school-aged students in Ahvaz, south-west Islamic Republic of Iran. In a descriptive, cross-sectional study, blood samples were obtained from 640 students (382 boys and 258 girls) aged 6-17 years during 2010-2011. All students had received a full course of pertussis whole-cell vaccination at ages 2, 4, 6 and 18 months and 4-6 years. Using a Bordetella IgG ELISA kit, pertussis-IgG was detected in 301 (47.0%) students. No statistically significant differences in pertussis-IgG levels were found between girls and boys or across different age groups. The findings show that the overall level of pertussis-IgG seropositivity was unacceptable. Booster vaccination with an acellular pertussis vaccine should be considered in adolescents and/or adults in our region.