Incidence of Norovirus-Associated Diarrhea, Shanghai, China, 2012-2013.

We conducted sentinel-based surveillance for norovirus in the Pudong area of Shanghai, China, during 2012-2013, by analyzing 5,324 community surveys, 408,024 medical records, and 771 laboratory-confirmed norovirus infections among 3,877 diarrhea cases. Our analysis indicated an outpatient incidence of 1.5/100 person-years and a community incidence of 8.9/100 person-years for norovirus-associated diarrhea.