Rotavirus vaccine: current status & future prospects.

A number of rotavirus vaccines, live attenuated, killed, and subunit, genetically engineered vaccines have been developed to control infantile diarrhoea. Field trials in several parts of the world have met with moderate or no success as the vaccinees failed to develop heterotypic protection. The failure of vaccine to control rotavirus diarrhoea may be due to the lack of understanding of the neonatal mucosal immune response, evolution of reassortant strains in nature and seasonal re-emergence of different types of strains in the field situation.