Seroprevalence of Bordetella pertussis toxin antibodies in children and adolescents in Tunis, Tunisia

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.

Cross-sectional seroprevalence study of antibody to Bordetella pertussis toxin in western Saudi Arabia: is there a need for a vaccine booster dose for adolescents and young adults?

“…In Tunisia, 12.3% of adolescents (13-18 years) were seropositive with anti-PT IgG antibodies indicative of recent infection/exposure to BP. 12 In a Hungarian study, 14.8% of the adults population screened were seropositive. 13 The majority of the population investigated (85.2%) were considered at increased risk of BP infection due to waning immunity.…”

“…Bordetella pertussis (BP) has continued to spread even though infants and children have a high vaccine coverage. 12 Adolescents and adults are identified as the primary source of infection for newborns and young infants. 13 It is, therefore, of great importance to prevent and early detect pertussis among those populations.…”

Bordetella pertussis in School-Age Children, Adolescents, and Adults: A Systematic Review of Epidemiology, Burden, and Mortality in Africa

“…There were five studies which reported epidemiology data for pertussis in Africa, namely Senegal [ 27 ], Tunisia [ 28 ], Algeria [ 29 ], Nigeria [ 30 ], and Uganda [ 31 ], and seven studies which reported sero-epidemiology in Senegal [ 32 ], Cameroon [ 33 ], South Africa [ 34 ], Tunisia [ 35 , 36 ], Morocco [ 37 , 38 ], and Gambia [ 39 ]. There were seven studies with mortality data including Nigeria [ 30 , 40 ], Ethiopia [ 41 ], Morocco [ 42 ], South Africa [ 43 , 44 ], and Senegal [ 27 ].…”

“…A seroprevalence study among healthcare workers (HCWs) at the same children's hospital during the same surveillance period confirmed that pertussis was circulating in hospital settings and affecting HCWs in close contact with infants [35]. [36].…”

Seroprevalence of pertussis in Madagascar and implications for vaccination

“…The EUROIMMUN kit has a high specificity and sensitivity compared to the other commercialised kits summarised in the Annex Table. Although this kit is commonly used for diagnosis, it has previously been used to estimate seroprevalence [23]. All experiments were conducted at the laboratories of Experimental Bacteriology of the Institut Pasteur de Madagascar (IPM) according to the manufacturer's manual.…”