Efficacy and safety of high-dose rhesus-human reassortant rotavirus vaccine in Native American populations.
OBJECTIVE
We compared the efficacy, safety, and immunogenicity of a rhesus rotavirus tetravalent vaccine (RRV-TV), a rhesus rotavirus monovalent (serotype 1) vaccine (RRV-S1), and placebo in healthy American Indian infants for two rotavirus seasons.


METHODS
Infants aged 6 to 24 weeks were enrolled in a randomized, double-blind efficacy study. Infants were orally administered RRV-TV (4 x 10(5) plaque-forming units per dose), RRV-S1 (4 x 10(5) plaque-forming units per dose), or placebo at 2, 4, and 6 months of age. Stools collected during episodes of gastroenteritis were tested for detection of rotavirus antigen. A total of 1185 infants received at least one dose of a study vaccine or placebo, and 1051 received all three doses according to the protocol.


RESULTS
During the first year of surveillance, the estimates of vaccine efficacy (with 95% confidence interval) for preventing rotaviral gastroenteritis were 50% (26, 67) for RRV-TV and 29% (-1, 50) for RRV-S1. In this population only 6% of rotaviral gastroenteritis episodes among placebo recipients were associated with type G1 disease. For severe disease the estimates of vaccine efficacy were higher: 69% (29, 88) for RRV-TV and 48% (-4, 75) for RRV-S1.


CONCLUSIONS
These data indicate that RRV-TV is moderately efficacious in preventing all episodes of gastroenteritis caused by rotavirus and is most efficacious against the severe disease characteristic of rotaviral illness.
Santosham
M
M
Department of International Health, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205, USA.
Moulton
L H
LH
Reid
R
R
Croll
J
J
Weatherholt
R
R
Ward
R
R
Forro
J
J
Zito
E
E
Mack
M
M
Brenneman
G
G
Davidson
B L
BL
D004311:Double-Blind Method; D005759:Gastroenteritis / Q000175:diagnosis; D006801:Humans; D007198:Indians, North American; D007223:Infant; D012189:Retrospective Studies; D012400:Rotavirus Infections / Q000276:immunology / Q000517:prevention & control*; D022243:Rotavirus Vaccines; D012720:Severity of Illness Index; D014613:Vaccines, Attenuated / Q000008:administration & dosage* / Q000009:adverse effects; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000009:adverse effects
D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated; D014765:Viral Vaccines; C052014:rhesus rotavirus vaccine