Clinical Trial: Pertussis Immunization During Pregnancy: Effect in Term and Preterm Infants

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Pertussis Immunization During Pregnancy: Assessment of the Role of Maternal Antibodies on Immune Responses in Term and Preterm Infants: the MAMA Study

Brief Summary:

Young infants are most vulnerable to severe disease and even death when infected with Bordetella Pertussis. The current vaccines and vaccination programs do not guarantee protection of neonates. During the last weeks of pregnancy, maternal IgG antibodies are transferred actively to the fetus. Administration of a pertussis containing vaccine during pregnancy offers protection through high titers of maternal antibodies transferred to the child. Since transplacental transport is immature, infants who are born prior to 37 weeks of gestation, might be vulnerable to pertussis infection even though maternal vaccination was administered, but specific data are lacking. The primary aim of this observational study is to measure whether vaccination during pregnancy offers protection to preterm born infants through higher titers of maternal antibodies, despite immature transplacental transport. Four cohorts of mother-infant pairs will be recruited: term versus preterm born infants, born from either vaccinated women or not vaccinated women. These mother-infant pairs are recruited according to the vaccination status of the mother and to the gestational age at delivery. Pertussis specific antibody titers (anti-Pertussis Toxin, anti-Filamentous haemagglutinin, anti-Pertactin titers) will be monitored in blood samples of the mothers at delivery to measure the possible influence of both gestational age and maternal vaccination status. In order to measure the decline of maternal antibodies in the first weeks of life, blood will be taken from cords as well as from infants at 8 weeks of age, before the first infant pertussis vaccine is administered.

Pertussis antibodies to the same antigens will be measured in all infants after a primary series of acellular pertussis vaccines administered at 8,12 and 16 weeks of age and before and after a booster dose in the second year of life.

Anti-Pertussis Toxin, anti-Filamentous Haemagglutinin and anti-pertactin immunoglobulin IgG titers, measured in blood samples taken from cord and at week 8 postpartum in all participating infants



Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Titers of pertussis specific antibodies in infants after 3 doses of a pertussis vaccine [ Time Frame: At the age of 5 months ]
    Anti-Pertussis Toxin, anti-Filamentous Haemagglutinin and anti-pertactin immunoglobulin IgG titers, measured in blood samples taken at 5 months (after a primary series of 3 vaccines)
  • Titers of pertussis specific antibodies in infants before and after a fourth dose of a pertussis vaccine [ Time Frame: From 13 to 16 months ]
    Anti-Pertussis Toxin, anti-Filamentous Haemagglutinin and anti-pertactin immunoglobulin IgG titers, measured in blood samples taken before and 1 month after a fourth pertussis vaccine
  • Th1 immune responses in preterm and term born infants before and after a primary series of infant pertussis vaccines [ Time Frame: From 8 weeks of age until 16 months of age ]
    Measurement of Th1 markers in a convenience sample of infants after primary and booster pertussis vaccination
  • Th2 immune responses in preterm and term born infants before and after a primary series of infant pertussis vaccines [ Time Frame: From 8 weeks of age until 16 months of age ]
    Measurement of Th2 markers in a convenience sample of infants after primary and booster pertussis vaccination
  • Titers of pertussis specific IgA antibodies in breast milk [ Time Frame: From birth until 3 months postpartum ]
    Measurement of anti-Pertussis Toxin IgA, total IgA and lactoferrin titers in breast milk samples taken at birth, at week 4, 8 and 12


Original Secondary Outcome: Same as current

Information By: Universiteit Antwerpen

Dates:
Date Received: July 22, 2015
Date Started: January 2015
Date Completion: December 2018
Last Updated: July 29, 2015
Last Verified: July 2015