association with nonclassical astroviruses in pediatric population. This child had previously tested negative for Norovirus, Sapovirus, and HAstV. In this study, the observed low frequency (0.4%) of nonclassical astroviruses is similar to the rates found, in fecal samples from children with AGE symptoms, in other regions of the world. This study was the first to identify HAstV-MLB1 in the Mid-West region of Brazil, the data will contribute to the molecular epidemiology of novel astroviruses in the pediatric population.