Rotavirus vaccine efficacy: current status and areas for improvement

Carvalho, Miguel F.; Gill, Davinder

Growing evidence suggests that more studies are required to further validate and identify critical Rotavirus entry factors in individuals with different genetic backgrounds. 15, 129 Exploring and potentially improving emerging cell culture systems that are better mimics of gut tissue 68 could prove very useful as they would assist in identifying and evaluating specific Rotavirus entry factors in cell cultures representing genetically diverse individuals. These specific entry factors could potentially be used as markers to easily probe children's genetic backgrounds with low cost kits as preliminary stages to mass vaccination campaigns, following which tailored vaccines would be administered to each individual. Furthermore, it could be important to design decoys based on pathogen entry factors that are tailored to children's genetic backgrounds and prevalent strains in a given area. For instance strain N155 recognizes hosts' lacto-N-biose and N-acetyllactosamine and affects Indian newborns only. 15 Blocking these receptors with suitable decoys would likely antagonize entry of strain N155. Hence, tailored medications could be administered to genotyped children days before vaccination, therefore reducing the incidence of gastroenteritis prior to vaccination (and increasing the efficiency of immunization) while favouring entry of vaccine, rather than pathogenic strains. It would be necessary to evaluate ideal dosing/half-life of decoys as well as to consider whether vaccines are being administered during high or low Rotavirus season. Having ascertained the genetic makeup of local populations regarding Rotavirus entry factors, it would be equally important to monitor the strains that naturally occur in any given region, as is the case for annual influenza immunization campaigns. Dominant strains would continue guiding the design of new vaccines and their deployment would be adjusted to the geographic areas and patients in question.