title: Forecasting Epidemiological Consequences of Maternal Immunization.
abstract: BACKGROUND
  The increase in the incidence of whooping cough (pertussis) in many countries with high vaccination coverage is alarming. Maternal pertussis immunization has been proposed as an effective means of protecting newborns during the interval between birth and the first routine dose. However, there are concerns regarding potential interference between maternal antibodies and the immune response elicited by the routine schedule, with possible long-term population-level effects.
  
  
  METHODS
  We formulated a transmission model comprising both primary routine and maternal immunization. This model was examined to evaluate the long-term epidemiological effects of routine and maternal immunization, together with consequences of potential immune interference scenarios.
  
  
  RESULTS
  Overall, our model demonstrates that maternal immunization is an effective strategy in reducing the incidence of pertussis in neonates prior to the onset of the primary schedule. However, if maternal antibodies lead to blunting, incidence increases among older age groups. For instance, our model predicts that with 60% routine and maternal immunization coverage and 30% blunting, the incidence among neonates (0-2 months) is reduced by 43%. Under the same scenario, we observe a 20% increase in incidence among children aged 5-10 years. However, the downstream increase in the older age groups occurs with a delay of approximately a decade or more.
  
  
  CONCLUSIONS
  Maternal immunization has clear positive effects on infant burden of disease, lowering mean infant incidence. However, if maternally derived antibodies adversely affect the immunogenicity of the routine schedule, we predict eventual population-level repercussions that may lead to an overall increase in incidence in older age groups.
authors.affiliation: Odum School of Ecology.|Center for the Ecology of Infectious Diseases.
authors.forename: Ana I
authors.initials: AI
authors.lastname: Bento
authors.affiliation: Odum School of Ecology.|Center for the Ecology of Infectious Diseases.|Department of Infectious Diseases, University of Georgia, Athens.
authors.forename: Pejman
authors.initials: P
authors.lastname: Rohani
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology*; D005260:Female; D005544:Forecasting; D006801:Humans; D007109:Immunity; D007112:Immunity, Maternally-Acquired; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018811:Maternal Exposure; D008875:Middle Aged; D008962:Models, Theoretical; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology*; D014611:Vaccination; D014917:Whooping Cough / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control*; D055815:Young Adult
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine
keywords: blunting; interference; maternal immunization; pertussis; routine vaccination