Abstract
Norovirus gastroenteritis remains a leading cause of morbidity and is still a major public health problem worldwide. The virus usually causes mild and self-limiting gastroenteritis symptoms in all age groups, mainly through the fecal-oral transmission route. However, the virus is highly contagious, relatively stable in the environment, and has long virus-shedding duration. These characteristics result in frequent outbreaks and make the control of the outbreaks difficult. In addition, the diversity of norovirus genetic characteristics and the emergence of new variants every one or two years may make the virus to escape the immunity. Moreover, the human immune response to norovirus infection still remains unclear and recurrent infection is possible. The diagnosis of norovirus infection is mainly based on reverse transcription polymerase chain reaction (RT-PCR), Loop-mediated isothermal amplification (LAMP), and immunochromatography (IC). There are no specific anti-norovirus drugs and treatment focuses mainly on supportive care, especially preventing and treating dehydration. Development of a norovirus vaccine has many difficulties and limitations, but some progress and some vaccine candidates have passed a phase II clinical trial. To prevent norovirus infection, hygiene is still the key point. Moreover, laws, regulations, and official guidelines are issued to help to manage norovirus infection and outbreak. This review provides an overview of norovirus infection and further discusses key characteristics of the virus, along with pathogenesis, clinical manifestation, diagnosis, treatment, prevention and control of the virus infection. We also view the virus through the lens of foodborne illnesses, and cover the current situation of the disease in Japan and research progress made so far.
