BACKGROUND: Most acute gastroenteritis (AGE) episodes in children in the United States are attributed to norovirus, whereas very little information is available on adenovirus 40/41 (AdV40/41), astrovirus, or sapovirus. The New Vaccine Surveillance Network (NVSN) conducted prospective, active, population-based AGE surveillance in young children. METHODS: We tested and typed stool specimens collected between December 2011 and June 2016 from 1 NVSN site in Kansas City for the 3 viruses, and calculated hospitalization and emergency department (ED) detection rates. RESULTS: Of 3205 collected specimens, 2453 (76.5%) were from AGE patients (339 inpatients and 2114 ED patients) and 752 (23.5%) were from healthy controls. In patients with AGE, astrovirus was detected in 94 (3.8%), sapovirus in 252 (10.3%), and AdV40/41 in 101 (4.5%) of 2249 patients. In healthy controls, astrovirus was detected in 13 (1.7%) and sapovirus in 15 (2.0%) specimens. Astrovirus type 1 (37.7%) and genogroup I sapoviruses (59.3%) were most prevalent. Hospitalization rates were 5 (AdV40/41), 4 (astrovirus), and 8 (sapovirus) per 100 000 children <
11 years old, whereas ED rates were 2.4 (AdV40/41), 1.9 (astrovirus), and 5.3 (sapovirus) per 1000 children <
5 years old. CONCLUSIONS: Overall, AdV40/41, astrovirus, and sapovirus were detected in 18.6% of AGE in a large pediatric hospital in Kansas City.