Rotavirus immune responses and correlates of protection

Selected topics in the field of rotavirus immunity are reviewed focusing on recent developments that may improve efficacy and safety of current and future vaccines. Rotaviruses (RVs) have developed multiple mechanisms to evade interferon (IFN)-mediated innate immunity. Compared to more developed regions of the world, protection induced by natural infection and vaccination is reduced in developing countries where, among other factors, high viral challenge loads are common and where infants are infected at an early age. Studies in developing countries indicate that rotavirus-specific serum IgA levels are not an optimal correlate of protection following vaccination, and better correlates need to be identified. Protection against rotavirus following vaccination is substantially heterotypic; nonetheless, a role for homotypic immunity in selection of circulating postvaccination strains needs further study.

► Rotaviruses have developed multiple mechanisms to evade IFN innate immunity.
► Protection induced by natural infection and vaccination is lower in developing countries.
► Studies in developing countries indicate that serum IgA is not an optimal correlate of protection for RV vaccines.
► Protection against RV is highly heterotypic.
► A role for homotypic immunity in selection of postvaccination ‘escape’ strains needs further study.