The seroepidemiology of Immunoglobulin G antibodies against pertussis toxin in China: a cross sectional study

Blood samples were obtained from 1313 healthy individuals aged 0 to 95？years in Guangdong province of China throughout September 2010. Serum IgG antibodies against PT were determined by commercial ELISA kits. Subjects with concentration of anti-PT IgG higher than 30？IU/mL were indicated to have recent Bordetella pertussis infection, if they have not received a booster dose of pertussis vaccine within one year.Of the 1313 study subjects, 117 (8.91%) were found to have anti-PT antibodies higher than 30？IU/mL. The estimated incidence of recent infection was thus 9395 per 100,000 for individuals older than 7？years. Peaks of the estimated incidence rate of recent infection were found to be 11561 per 100,000 in age group of 41–50？years and 11428 per 100,000 in the group aged 13–19？years.Our study indicated that B.pertussis infections are considerablely common, particularly in adolescents and adults in China. The study also stresses the importance of laboratory diagnosis for pertussis and employment of booster dose of pertussis vaccine in adolescents and adults in this country.