Calicivirus – NoV

Caliciviruses are a group of non-enveloped single-stranded positive-sense RNA viruses, including norovirus. In the United States, CDC estimates that there are approximately 19 to 21 million annual cases of acute gastroenteritis caused by human norovirus (HuNoVs). The norovirus genome is organized into 3 open reading frames with the first encoding non-structural proteins, the second encoding the major structural protein (VP1), and the third encoding the minor structural protein (VP2). Noroviruses are phylogenetically classified into at least six genogroups (GI–GVI), with each genogroup divided into several genotypes. Genogroups GI, GII, and GIV contain human pathogens.