Rotavirus vaccine will have an impact in Asia
Authors: Carl D. Kirkwood, A. Duncan Steele
Journal: PLoS Medicine (2017)

Diarrhea remains the second leading infectious cause of death among children under five years of age, with more than half a million deaths each year.Rotavirus disease accounts for 25%-30% of all severe diarrhea cases [1].While every child is at risk of rotavirus infection, the vast majority of rotavirus deaths occur in low-and middle-income countries, particularly in sub-Saharan Africa and South Asia, where access to treatment for severe rotavirus-related diarrhea may be limited or absent.Rotavirus immunization is well recognized as the best approach to protect children from mortality and morbidity caused by severe rotavirus disease.In 2009, the World Health Organization (WHO) recommended that all countries should include rotavirus vaccines in their national immunization programs, particularly those with high child mortality due to diarrhea [2].Currently, 84 countries have introduced rotavirus vaccines into their national immunization programs, including 41 Gavi-eligible countries with financial support for vaccine procurement.The uptake of rotavirus vaccines in sub-Saharan Africa and the Americas has been excellent; however, progress in Asia has been insignificant, with a notable lack of introductions into national immunization programs despite the wellcharacterized burden of rotavirus disease [3,4].Rotavirus disease and hospitalization have been significantly reduced in high-and middle-income countries, with multiple vaccine-effectiveness studies documenting their powerful impact [5].Moreover, recent vaccine-effectiveness studies in low-middle-and low-income countries in Latin America and Africa have shown dramatic reductions in rotavirus-associated morbidity and mortality [6][7][8].Thus, the large infant population at risk in Asia is a priority for future rotavirus introduction efforts.The reasons for delayed vaccine introduction likely vary by country, with multiple stages along the pathway to implementation posing hurdles, including evidence gathering, decisionmaking, planning, and introduction.The driver for introduction may also differ; for example, perceived health benefits may be the primary reason in one area, and economic benefits may be more important in another.However, the limited data from low-resource populations across Asia, which are needed to provide evidence of the clinical protection that rotavirus vaccination provides against severe diarrhea, have also likely stalled the uptake of rotavirus vaccines within these regions.In a recent study in PLOS Medicine, John Victor and colleagues describe effectiveness of the human monovalent rotavirus vaccine, (Rotarix) in Bangladesh [9], providing evidence that should help to change the status quo in the region.Victor and colleagues' study is the first to evaluate protection in infants in a low-resource population in Asia, using the WHO-recommended schedule at 6 and 10 weeks of age (i.e., the visits corresponding to the first and second dose of diphtheria-pertussis-tetanus-containing vaccine [DPT 1 and DPT 2]).The trial used a cluster-randomized village approach, comparing Rotarix vaccination integrated into the routine childhood immunization program in Bangladesh to the standard childhood immunizations without rotavirus vaccine but still utilizing oral rehydration salt (ORS) and other routine