Inclusion Criteria for Pregnant women:  Permanent Resident in selected villages in Matlab HDSS MCH-FP area Age 18 - 49 years old 28 to 34 weeks of gestation at the time of enrollment Willing to stay in the study village for the next 20 months  Exclusion Criteria for Pregnant Women:  Refusal to provide consent for participation Unable to participate in the full length of the study period Known allergy to egg or any product of vaccine Sick (has documented fever and respiratory illness) at the time of enrollment Pregnancy with complications such as chronic pulmonary (including asthma), cardiovascular, renal, hepatic, hematologic (including sickle cell disease), or metabolic disorders (including diabetes mellitus and obesity) or neurologic and neurodevelopment conditions, cancer, immunosuppression, and, multiple pregnancy) Received any vaccine /immune component in last 4 weeks Participated in any research study in the last 3 months  Inclusion Criteria for Children:  Permanent Resident in selected villages in Matlab HDSS MCH-FP area Age 6 to 59 months old Parents/guardians confirm their willingness to stay in the study village for the next 20 months  Exclusion Criteria for Children:  Parents refuse to provide consent for participation Unable to participate in the full length of the study period Known allergy to egg or any product of vaccine Sick children (has documented fever and respiratory illness) at the time of enrolment Chronic illness such as chronic pulmonary (including asthma), cardiovascular, renal, hepatic, hematologic (including sickle cell disease), or metabolic disorders (including diabetes mellitus and obesity) or neurologic and neurodevelopment conditions, cancer, and immunosuppression Received any vaccine /immune component in last 4 weeks Participated in any research study in the last 3 months