Noroviruses (NoVs) are single-stranded, positive-sense RNA viruses belonging to the Caliciviridae family. NoVs cause >90% of non-bacterial epidemic acute gastroenteritis, affecting people of all ages worldwide. In children, NoV is the second most important etiological agent (next to rotavirus) causing dehydrating diarrhea.
The symptoms of NoV infection in humans are sudden onset and frequent vomiting and diarrhea that often lead to dehydration. NoV infections cause an estimated ~23 million cases of acute gastroenteritis each year in the United States alone.
Noroviruses are highly contagious and can be spread quickly by person-to-person transmission, through contact with contaminated environmental surfaces, or by contaminated food and water, which are common sources of large outbreaks in a variety of settings. These outbreaks are especially prevalent in semi-closed communities, such as hospitals, cruise ships, nursing homes, the military and schools.
Human NoVs remain difficult to study because of the lack of appropriate cell culture and small animal models and the NoV disease is difficult to control because of the wide spread nature and the lack of effective treatment and prevention methods. In addition, the potential threat by bioterrorism with NoVs increases the need for an effective vaccine against NoVs.
The Yuan lab is conducting natural history studies of currently circulating human noroviruses in gnotobiotic pigs to establish the gnotobiotic pig model of human norovirus infection and disease. The animal model will be used to characterize the safety, immunogenicity and broadness of candidate norovirus P particle vaccines in protection against various noroviruses.