Maternal Determinants of Infant Immunity to Pertussis

Inclusion Criteria: * For non-pregnant \& pregnant women Age between 18 and 45 years Eligible for Tdap vaccination * For infants Born to mothers vaccinated or not with Tdap Vaccinated with hexavalent vaccine Age between 2 and 3 months Exclusion Criteria: * For pregnant and non-pregnant women * Inability to understand the nature and extent of the study and the procedures required * Grade III/IV anemia, * Acute infection at the time of immunization * Chronic infections such as Hepatitis B Virus (HBV), Hepatitis C Virus (HCV) or Human Immunodeficiency Virus (HIV) infection, acute toxoplasmosis * Current or recent use of immunosuppressive drugs * Active neoplasia * Other vaccine(s) administered at the same time as Tdap vaccination (wash out of 4 weeks after others vaccinations and 28 days after Tdap vaccination ) * For pregnant women * Risk of premature delivery or intrauterine growth retardation * Twin or triplet pregnancies * For non-pregnant women Last Tdap vaccination \< 12 months before For infants: * Infants born before 35 weeks of gestation * Birthweight below 2.5 kg, * Severe neonatal distress * Serious congenital abnormalities or congenital infection.