Pertussis Vaccination Among HIV-infected and HIV-uninfected Pregnant Women

Inclusion Criteria: * Pregnant women age ≥18 years to \<39 years (vaccinated group only). * Gestational age 20-36 weeks documented by the approximate date of the last menstrual period and corroborated by physical or sonargraphic exam (vaccinated group only). * Documented to be HIV-infected or HIV-uninfected. * Good general maternal health. * Able to understand and comply with planned study procedures. * Able and willing to provide written informed consent for themselves and infant Exclusion Criteria: * Receipt of any live licensed vaccine ≤14 days prior to study initiation. * Any significant (in the opinion of the site investigator) acute illness. * Use of anti-cancer systemic chemotherapy or radiation therapy ≤48 weeks of study enrolment or has immunosuppression as a result of an underlying illness or treatment. * Long term use of glucocorticoids, including oral or parenteral prednisone ≥20 mg/day or equivalent for more than 2 consecutive weeks (or 2 weeks total) ≤12 weeks of study entry, or high-dose inhaled steroids (\>800 mcg/day of beclomethasone dipropionate or equivalent) ≤12 weeks before study entry (nasal and topical steroids are allowed). * Receipt of corticosteroids for preterm labour ≤14 days before study entry. * Receipt of immunoglobulin or other blood products (with exception of Rho D immune globulin) ≤12 weeks prior to enrolment in this study or is scheduled to receive immunoglobulin or other blood products (with the exception of Rho D immune globulin) during pregnancy or for the first 24 weeks after delivery. * Receipt of IL2, IFN, GMCSF or other immune mediators ≤12 weeks before enrolment. * Uncontrolled major psychiatric disorder. * History of a severe adverse reaction to previous vaccines (vaccinated group only). * Any condition that would, in the opinion of the site investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol. * Pregnancy complications (in the current pregnancy) such as pre-term labour, hypertension (BP \>140/90 in the presence of proteinuria or BP \>150/100, with or without proteinuria or currently on antihypertensive medication) and pre-eclampsia.