Phase I/II Descending Age Study of P2VP8 Subunit Parenteral Rotavirus Vaccine in Healthy Toddlers and Infants

Inclusion criteria

• healthy infants/toddlers as established by medical history and clinical examination before entering study
• age:

• toddler cohort: > or = 2 and <3 years old at the time of enrollment
• infant cohort: > or = 6 and <8 weeks at the time of enrollment
• parental ability and willingness to provide informed consent
• parental intention to remain in the area with the child during the study period.

Exclusion criteria

• Presence of fever on the day of enrollment
• Acute disease at the time of enrollment
• Concurrent participation in another clinical trial throughout the entire timeframe for this study
• Presence of malnutrition or any systemic disorder (cardiovascular, pulmonary, hepatic, renal, gastrointestinal, hematological, endocrine, immunological, dermatological, neurological, cancer or autoimmune disease) as determined by medical history and/or physical examination that would compromise the participant's health or is likely to result in nonconformance to the protocol
• For infant cohort, history of premature birth (<37 weeks gestation)
• History of congenital abdominal disorders, intussusception, or abdominal surgery
• Known or suspected impairment of immunological function based on medical history and physical examination
• For infant cohort only, prior receipt of rotavirus vaccine
• A known sensitivity or allergy to any components of the study vaccine
• History of anaphylactic reaction
• Major congenital or genetic defect
• Participant's parents not able, available or willing to accept active weekly follow-up by the study staff
• Has received any immunoglobulin therapy and/or blood products since birth or planned administration during the study period
• History of chronic administration (defined as more than 14 days) of immunosuppressant medications, including corticosteroids. Infants on inhaled or topical steroids may be permitted to participate in the study
• Any medical condition in the parents/infant that, in the judgment of the investigator, would interfere with or serves as a contraindication to protocol adherence or a participant's parents' ability to give informed consent
• HIV infection

• For toddlers, to be assessed by HIV ELISA
• For infants, to be assessed by PCR, if mother is not known to be negative (negative test result between 24 weeks gestation and screening)