Influenza Vaccine Trial in HIV Uninfected Pregnant Women

Inclusion Criteria: * Pregnant women age 18 years to less than 39 years. * Gestational age greater than or equal to 20 weeks to less than 34 weeks documented by the approximate date of the last menstrual period and corroborated by physical exam. * Documented to be HIV-1 uninfected on two assays used in the PMTCT program undertaken within 12 weeks of study enrolment. * Able to understand and comply with planned study procedures. * Provides written informed consent prior to initiation of study. Exclusion Criteria: * Receipt of TIV, other than through the study, during the current influenza season documented by medical history or record. * Receipt of any live licensed vaccine less than or equal to 28 days or inactivated licensed vaccine (except for tetanus toxoid vaccine) less than to equal to 14 days prior to study-vaccine. * Participants in the nested immunogenicity cohort cannot receive ANY vaccine (including tetanus toxoid) within 14 days of the study-vaccine. * Receipt of a non-licensed agent (vaccine, drug, biologic, device, blood product, or medication) less than or equal to 28 days prior to vaccination in this study, or expects to receive another non-licensed agent before delivery unless study approval is obtained. * Any significant (in the opinion of the site investigator) acute illness and/or oral temperature greater than or equal to 38 degrees C ≤ 24 hours prior to study entry. * Use of anti-cancer systemic chemotherapy or radiation therapy ≤ 48 weeks of study enrollment, 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 labor ≤ 14 days before study entry. * Receipt of immunoglobulin or other blood products (with exception of Rho D immune globulin) ≤ 12 weeks prior to enrollment 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 enrollment. * Uncontrolled major psychiatric disorder. * History of a severe adverse reaction to previous TIV. * 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 labor, hypertension (systolic blood pressure ≥ 140 and/or diastolic blood pressure ≥ 90 mm Hg) and pre-eclampsia.