Abstract
Pertussis remains a public health concern in most countries. This cross-sectional study aims to investigate the distribution of pertussis toxin antibodies (anti-PT IgG) in Tunisian children and adolescents aged 3-18 years, to define optimal age for booster vaccination. Anti-PT IgG concentrations of enrolled participants were measured using commercial enzyme-linked immunosorbent assay. Concentrations were classified as: indicative of current/recent infection if ⩾100 IU/ml, indicative of recent exposure to Bordetella pertussis within the last year if 40-100 IU/ml and less likely revealing a recent exposure to B. pertussis if <40 IU/ml. Between March and June 2018, a total of 304 participants (mean age: 9.3 years) were included in this study. Overall, 12.8% (95% confidence interval (CI) 9.1%-16.6%) were seropositive (IgG levels ⩾40 IU/ml). Among them, 14.7% (95% CI 2.3%-23.3%) had levels indicative of a current/recent infection. The multivariate Poisson regression analysis suggested associations between female gender, as well as age group 13-18 years and 3-5 years and higher anti-PT IgG concentrations. Our results are consistent with the notion that vaccine-induced immunity decline, as well as circulation of pertussis among school children and adolescents enables them to be reservoirs of infection and disease transmission to vulnerable infants. Booster dose of acellular pertussis vaccine for school entrants is therefore recommended.
Highlights
Pertussis, mainly caused by the bacterium Bordetella pertussis, is a highly contagious infectious disease [1]
This study aims to determine prevalence of immunoglobulin G (IgG) antibodies to pertussis toxin (PT) amongst a cohort of pre-school, school children and adolescents to evaluate the distribution of anti-PT IgG in different age groups and to assess age of decrease of vaccine-acquired immunity
Concentrations between 40 and 100 International Units/ml (IU/ml) were considered to indicate a recent contact with B. pertussis within the last year, while anti-PT IgG levels
Summary
Mainly caused by the bacterium Bordetella pertussis, is a highly contagious infectious disease [1]. New-borns and infants, not or partially vaccinated, are mostly affected [2] They have the highest risk of eventual malignant pertussis manifested by severe complications including seizures, pneumonia, encephalopathy and a marked leucocytosis [3, 4]. An increase in pertussis incidence among old children and adolescents in some countries has been well-described [5] These age categories, especially family members, seem to be a potential source of pertussis transmission to young infants [2, 6]. Contributing factors of this increase could be waning of vaccine-induced immunity, pathogen adaptation and changes in disease susceptibility [5, 7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
