Antiviral Prophylaxis and Infant Vaccination to Prevent Perinatal Hepatitis B Infection

Inclusion Criteria: * Pregnancy * Age ≥18 years * Negative HIV antibody test during current pregnancy * Positive HBsAg test during current pregnancy * Positive HBeAg using a rapid test during current pregnancy * Absence of clinical symptoms of liver disease * Gestational age of 28 weeks (+/- 7 days) based on the obstetrician judgment guided by the review of the date of last menstruation period. * Willing and able to provide written informed consent * Agreeing to bring her infants(s) at the planned study visits at one of the study site until the last visit (18 months after birth) and to inform the site investigators if plans to move to another place and not be able to return to the clinic * Understand the need for adequate infant immunization for her infant(s) and accept that blood draws will be performed to determine the infant HBV infection status Exclusion Criteria: * Receipt of anti-HBV antivirals at any time during the last 9 months * Known liver cirrhosis or evidence of hepatocellular carcinoma * Creatinine clearance \<50 ml/min, calculated using the Cockcroft-Gault formula * Confirmed dipstick proteinuria \>1+ (\>30 mg/dL) or normoglycemic glycosuria * Evidence of pre-existing fetal anomalies incompatible with life * Any concomitant condition or treatment that, in the view of the clinical site investigator, would contraindicate participation or compromise adherence to treatment and satisfactory follow up in the study.