Seroepidemiology of Bordetella pertussis Infection in Fresh College Students in Iran: A Multicenter Study

Background: Pertussis is a highly communicable, vaccine-preventable respiratory disease; which may circulate even in populations with high vaccination coverage. Although frequent, but it is often underestimated as a cause of prolonged cough illness in both children and adults. Without boosting, the protection of the childhood vaccination would be minimal after 10 years. The need for adult booster vaccination depends on the national epidemiology. Objectives: The aim of this study was to evaluate the seroepidemiological incidence of Pertussis in fresh college students in four majors. Patients and Methods: In a cross sectional multicenter study, blood samples were obtained from 1617 junior students of four universities. None had received Pertussis booster vaccine in the preceding 10 years. Serum immunoglobulin G (IgG) antibody for Pertussis toxin antigen was measured. Some social and demographic determinants including age, sex and number of family members were recorded. Results: The mean age of participants was 19.64 ± 2.1 years; positive anti Pertussis toxin IgG levels (by cut point of 94 U/mL) was detected in 31.6%. Positivity rate was associated with sex but not with age or residential area. Conclusions: Pertussis continues to challenge medical and public health professionals. Recent reports of increases in the prevalence and incidence may be because of the limited time of protection of childhood vaccination. Our study can serve as one of the scarce population-based reports from developing countries. A universal cut point should be determined for diagnosis of seropositivity, and a booster of a cellular vaccine is recommended in adolescence.