Abstract
BackgroundPertussis (whooping cough) is well known to be underreported, particularly among adults, who can act as an infectious reservoir, potentially putting susceptible newborns at risk of serious illness. The purpose of this study was to estimate the seroprevalence of pertussis in adults in Hungary.MethodsThis epidemiological, cross-sectional study was conducted in adults in five general practitioners’ practices in Hungary. Serum anti-pertussis toxin immunoglobulin G (anti-PT IgG) antibody levels were analyzed using enzyme-linked immunosorbent assay. Sera were classified following manufacturer’s instructions as: strongly indicative of current/recent infection (≥1.5 optical density [OD] units); indicative of current/recent infection (≥1.0 OD units); seropositive (>0.3 OD units); or seronegative (≤0.3 OD units). Logistic regression was performed to describe the associations between seroprevalence and various characteristics.ResultsBetween 24th April 2014 and 24th April 2015, 1999 adults (60.6% female; mean age 47.4 ± 17.7 years) were included in the analysis. A total of 14.8% were seropositive for anti-PT IgG, 1.1% had a level indicative of current/recent infection, and 0.1% had a level strongly indicative of current/recent infection. Logistic regression showed significant relationships between increased rates of seropositivity and: age ≥60 years (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.39–2.80; p = .0002) or 18–29 years (OR, 1.67; 95% CI, 1.13–2.46; p = .0094) vs. 45–59 years; former smoker (OR, 1.46; 95% CI, 1.08–1.97; p = .014) or current smoker (OR, 1.38; 95% CI, 1.01–1.89; p = .045) vs. never smoker; and male (OR, 1.30; 95% CI, 1.01–1.68; p = .041) vs. female. Also, between increased rates of probable current/recent infection and current smoker (OR, 7.50; 95% CI, 2.32–24.31; p = .0008) or former smoker (OR, 4.07; 95% CI, 1.21–13.64; p = .023) vs. never smoker.ConclusionsApproximately 85% of the adults studied were seronegative and therefore susceptible to pertussis infection. Approximately 1% had anti-PT IgG levels indicative of current/recent pertussis infection, which could potentially be transmitted to susceptible young infants. Vaccination of adults is a key way to indirectly protect infants.Trial registrationClinical Trials.gov NCT02014519. Prospectively registered 12 December 2013.
Highlights
Pertussis is well known to be underreported, among adults, who can act as an infectious reservoir, potentially putting susceptible newborns at risk of serious illness
Test results were used to classify sera according to manufacturer pre-defined cut-off values as: strongly indicative of current/recent infection (≥1.5 optical density [Optical density (OD)] units; corresponds to 110 enzyme-linked immunosorbent assay (ELISA) units [EU]/mL against the United States (US) Food and Drug Administration standard Lot 3 [19]); indicative of current/recent infection (≥1.0 OD units [70 EU/mL]); seropositive (>0.3 OD units [18 EU/mL]; the sensitivity limit of the assay); or seronegative (≤0.3 OD units)
We found that males were significantly more likely to be seropositive than females; but not significantly more likely to have anti-PT Anti-pertussis toxin immunoglobulin G (IgG) levels indicative of current/recent infection
Summary
Pertussis (whooping cough) is well known to be underreported, among adults, who can act as an infectious reservoir, potentially putting susceptible newborns at risk of serious illness. As pertussis is a potentially life-threatening infection for newborns and unvaccinated infants [2], vaccination during infancy is recommended. Adults are at risk of pertussis infection due to waning immunity following immunization or natural. Pertussis during adulthood is generally not serious, it can result in morbidity and – more importantly – infected adults can pass on the infection to infants who have not been (fully) vaccinated [9]. Some European countries have introduced various combinations of: adolescent, adult, or elderly boosters; a “cocooning strategy” (vaccination of household members in contact with a newborn); or vaccination of pregnant women (to provide the infant with placentally transmitted antibodies) [11, 12]. Given that the notification rate in infants (age
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
