Human noroviruses (HuNoVs) cause a majority of gastroenteritis outbreaks across the globe and are the leading cause of severe childhood diarrhea and foodborne disease outbreaks in the United States. In impoverished countries, they are estimated to cause over one million clinic visits and 200,000 deaths in young children annually. However, the mechanisms used by noroviruses (NoVs) to infect the intestinal tract and cause disease are not well understood, primarily due to the paucity of cell culture and animal model systems. Recent major advances in developing such models now leave the field poised to tackle these critical questions. The goal of this opinion article is to propose a working model of early steps involved in intestinal infection by NoVs. In this model, NoVs bind carbohydrates on the surface of specific members of the intestinal microbiota and/or enterocytes and are then transcytosed across the intestinal epithelial barrier to gain access to their target immune cells.
A Working Model of How Noroviruses Infect the Intestine