A comparative trial of rhesus monkey (RRV-1) and bovine (RIT 4237) oral rotavirus vaccines in young children.

Heterologous live, oral rotavirus vaccines of rhesus monkey (RRV-1) and bovine (RIT 4237) origin were tested for immunogenicity, excretion of virus, and clinical reactions in six- to eight-month-old infants. Antibody response, indicating infection with the vaccine virus, was detected in 21 (88%) of 24 children receiving the RRV-1 vaccine and in 18 (75%) of 24 receiving the RIT 4237 vaccine. Excretion of virus in the stools within one week after vaccination was demonstrable in 84% of the RRV-1 and in 21% of the RIT 4237 vaccinees. RRV-1 vaccination was associated with a febrile response (over 38 C) that clustered on days 3 or 4 postvaccination in 64% of the recipient children. In addition, 20% of the RRV-1 vaccinees had watery stools on days 4 or 5. Fever on days 3 and 4 and loose stools were not seen in the RIT 4237 vaccinees. We concluded that in young children the RRV-1 (rhesus monkey) rotavirus vaccine is more immunogenic than the RIT 4237 (bovine) rotavirus vaccine, but vaccination with RRV-1 is associated with significant adverse reactions.