Travel CDC: Frozen raspberries were culprit behind 2019 norovirus outbreak on multiple cruises April 24, 2020Morgan Hines, USA TODAYComments Off on CDC: Frozen raspberries were culprit behind 2019 norovirus outbreak on multiple cruises Smoothies: Nutritious, delicious – and according to the CDC, the source of a norovirus outbreak that infected hundreds of cruise passengers in 2019.