A systematic review of the burden of pertussis disease in infants and the effectiveness of maternal immunization against pertussis

Abstract

Introduction: Infants too young to be fully immunized are the most vulnerable to severe pertussis disease. To close this susceptibility gap, passive infant immunization through vaccination of pregnant women against pertussis was first introduced in 2011 in the United States and has been extended since then to more than 40 countries. Areas covered: We conducted two systematic literature searches to describe the worldwide burden of pertussis disease in infants <6 months of age since 2005, and the effectiveness and impact of maternal pertussis vaccination in preventing infant pertussis since 2011. Expert opinion: Pertussis disease incidence rates in infants aged <2-3 months were substantial in all countries with available data, exceeding 1000 cases per 100,000 population during outbreaks. Virtually all pertussis deaths occurred in this age group. Data from Africa, Eastern Mediterranean, and Asia were limited, but suggest a similar or higher disease burden than in Europe or the Americas. Estimates of effectiveness of second/third trimester pertussis vaccination in preventing pertussis disease in <2-3 months old infants were consistently high (69%-93%) across the observational studies reviewed, conducted in various settings with different designs. Maternal vaccination programs appear to be achieving their goal of reducing the burden of disease in very young infants.

Lessons from a mature acellular pertussis vaccination program and strategies to overcome suboptimal vaccine effectiveness

“…They stated it could be given any time during pregnancy but recommended it preferably be given between 27-and 36-weeks' gestation to maximize antibody transfer [71]. Several other countries have adopted similar recommendations regarding Tdap vaccination of pregnant women to provide protection to newborns [72][73][74][75][76][77].…”

“…Prior to implementing maternal Tdap programs, several countries had high pertussis incidence rates among infants aged <2-3 months, which exceeded 1,000 cases per 100,000 population during outbreaks [77]. After instituting maternal Tdap vaccinations, many countries saw significant decreases in pertussis incidence among infants <1 years of age [3,74,[77][78][79][80]. Argentina observed a relative reduction of 44% in the incidence of pertussis among children 2-6 months of age after it began vaccinating pregnant with Tdap in 2012 [81].…”

“…The observed substantial decrease in incidence rates of disease among infants following maternal Tdap vaccination demonstrates that the vaccine is effective at protecting infants. Several studies have demonstrated that Tdap vaccination during pregnancy is 69-94% effective at protecting infants against disease and hospitalization in the first few months of life [77,84,85]. We estimated that Tdap during pregnancy was 69.0% (95% CI, 43.6-82.9) effective at protecting infants against pertussis during the entire first year of life [86].…”

Impact of Childhood and Maternal Vaccination against Diphtheria, Tetanus, and Pertussis in Colombia

“…The resurgence of pertussis reported worldwide has been explained by different factors including the loss of vaccine immunity over time and the reduction in vaccination coverage. 28 , 29 Although the effectiveness of maternal vaccination has been widely studied, 8 , 30 , 31 there is a need to strengthen epidemiological surveillance of pertussis and develop new approaches based on hospital reporting, to avoid late consultation, complications, and death. In our study, a percentage increase in hospitalization and mortality, higher frequency of cases in the dispersed rural area, and lower laboratory confirmation of cases were observed after the epidemic period compared with the epidemic period.…”

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

“…Therefore, the GPI strongly recommends the use of aP vaccine in pregnant women and also encourages booster doses in adolescents [ 159 ]. Several European countries currently recommend aP vaccine for pregnant women on the NIP, including Belgium, Czech Republic, Denmark, Ireland, Italy, The Netherlands, Slovenia, Spain and the UK [ 160 ].…”