Pertussis Immunization During Pregnancy: Effect in Term and Preterm Infants
- Conditions
- Pertussis
- Interventions
- Drug: Infant pertussis vaccination
- Registration Number
- NCT02511327
- Lead Sponsor
- Universiteit Antwerpen
- 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.
In addition, cellular mediated immune responses will be evaluated in a subgroup of infants before and after a primary series of infants vaccines. A last goal is to measure whether vaccination during pregnancy could offer additional maternal antibodies through breast milk. Again a comparison is made between preterm and term born infants, born from either vaccinated or unvaccinated women. The amount of lactoferrin and pertussis toxin specific IgA in breast milk samples will be measured in samples taken at birth (colostrum), and at several time points afterwards as long as breastfeeding is continued.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 232
Not provided
Not provided
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Preterm born infants of vaccinated women Infant pertussis vaccination Preterm born infants (\< 37 weeks of gestation) whose mothers have received an acellular pertussis vaccine during pregnancy, within the national recommended vaccination programme. Infant vaccination against pertussis is performed according to the national recommended schedule. Term born infants vaccinated women Infant pertussis vaccination Term born infants (\>= 37 weeks of gestation) whose mothers have received an acellular pertussis vaccine during pregnancy, within the national recommended vaccination programme. Infant vaccination against pertussis is performed according to the national recommended schedule. Preterm born infants unvaccinated women Infant pertussis vaccination Preterm born infants (\< 37 weeks of gestation) whose mothers have not received an acellular pertussis vaccine during pregnancy.Infant vaccination against pertussis is performed according to the national recommended schedule. Term born infants unvaccinated women Infant pertussis vaccination Term born infants (\>= 37 weeks of gestation) whose mothers have not received an acellular pertussis vaccine during pregnancy. Infant vaccination against pertussis is performed according to the national recommended schedule.
- Primary Outcome Measures
Name Time Method Titers of maternal pertussis specific antibodies From birth until 8 weeks of age 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
- Secondary Outcome Measures
Name Time Method Titers of pertussis specific antibodies in infants after 3 doses of a pertussis vaccine 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 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
Titers of pertussis specific IgA antibodies in breast milk 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
Titers of pertussis specific antibodies in infants in-between the fourth and fifth dose of a pertussis vaccine Around 3 years of age 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 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 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 antibodies in infants before and after a fifth dose of a pertussis vaccine From 5 to 6 years of age 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 & Th2 immune responses in preterm and term born infants before and after a fifth booster dose of a pertussis vaccine From 5 to 6 years of age Measurement of Th1 and Th2 markers in a convenience sample of infants before and after a pertussis booster vaccination
Trial Locations
- Locations (1)
University of Antwerp
🇧🇪Antwerp, Belgium