Risk factors for pertussis in adults and teenagers in England

Abstract

Pertussis is a vaccine-preventable respiratory infection caused by Bordetella pertussis which can be fatal in infants. Although high vaccine coverage led to prolonged disease control in England, a national outbreak of pertussis in 2011 led to the largest increase in over two decades, including a marked increase in cases aged ⩾15 years. A case-control study in four regions of England was undertaken to investigate risk factors for pertussis in adolescents and adults, specifically employment type and professional and household contact with children. Pertussis cases were laboratory-confirmed and aged ⩾15 years. Controls were recruited through general practitioner nomination. Demographic and risk factor information were collected using an online survey. Multivariable logistic regression was used to estimate independent associations with outcome. Two hundred and thirty-one cases and 190 controls were recruited. None of the four employment variables (social care, education, health sector, patient contact) were significantly associated with pertussis. Professional contact with children aged < 1 year was associated with a significantly reduced odds of pertussis [odds ratio (OR) 0·25, 95% confidence interval (CI) 0·08-0·78, P = 0·017]. Household contact with ⩾1 child aged 10-14 years was associated with significantly increased odds of pertussis (OR 2·61, 95% CI 1·47-4·64, P = 0·001). Occupational contact with very young children was associated with reduced odds of pertussis, probably due to immune boosting by low-level exposures to B. pertussis. Sharing a household with a young adolescent was a significant risk factor for pertussis in adults and older teenagers. The primary focus of the childhood pertussis vaccination programmes is to prevent infant disease. Although evidence is emerging that adolescent vaccination does not provide indirect protection to infants, our results highlight the importance of children aged 10-14 years in pertussis transmission to older adolescents and adults.

A multi-country, multi-year, meta-analytic evaluation of the sex differences in age-specific pertussis incidence rates

“…caring for their own children [12], or through exposure to sick children while working in daycare centers. Adults are a potential reservoir for exposure to pertussis in very young infants [2], although the exposure should be the same regardless of the infant's sex.…”

“…These include response to vaccine, behavioral and social factors [12], chromosomal factors, or an interaction between sex hormones and immune function affecting the clinical manifestations of the disease [13]. Establishment of the magnitude and consistency of the sex differences in the disease can provide important clues to the mechanism of disease.…”

Robust Humoral and Cellular Immune Responses to Pertussis in Adults After a First Acellular Booster Vaccination

“…The incidence of clinical pertussis cases strongly declined after the introduction of whole-cell pertussis (wP) vaccines in infant national immunization programs (NIP) in the 1940 and 1950s ( 1 ). Despite a consistently high vaccination coverage, an increase in numbers of pertussis cases is observed in many countries and in all age groups ( 2 – 5 ). Consequently, in addition to pre-school acellular pertussis (aP) booster vaccinations, several countries have implemented aP booster vaccinations for adolescents and adults ( 6 – 8 ).…”

Burden of Selected Infectious Diseases Covered by UK Childhood Vaccinations: Systematic Literature Review

“…Due to this high number of publications, and given the focus of our work on the most recent evidence, only studies published in or after 2012 as full publications were included in a post hoc selection, which resulted in 39 eligible publications [11, (reporting on 38 studies) ( Figure 1). Of these, 21 studies (22 publications) reported data on Hep B [20,21,23,25,26,[31][32][33][34]36,[38][39][40][41][42][43][44][45][46]48,49,52], nine on pertussis [6,18,22,24,30,50,51,53,54], five on H. influenzae [27][28][29]35,37] and one on poliomyelitis [47], tetanus [11], and diphtheria [19], respectively. Characteristics of the included studies can be found in Supplementary Tables 3-5.…”