Hospital-based surveillance for rotavirus diarrhea in Ulaanbaatar, Mongolia, April 2009 through March 2016.

This study found a relatively high prevalence of severe rotavirus-associated diarrhea disease in Mongolia and infants were the most affected. It highlights the urgent need for introduction of rotavirus vaccine into the national immunization program. Continued surveillance is crucial and pre-vaccine introduction rotavirus genotype patterns in Mongolia are valuable and can be followed post-introduction to assess vaccine impact.