<unk>  is a genetically diverse genus of single-stranded positive-sense RNA, non-enveloped viruses within the family Caliciviridae. Together with norovirus,<unk> es are the most common cause of acute gastroenteritis (commonly called the "stomach flu" although it is not related to influenza) in humans and other animals. It is a monotypic taxon, containing only one species, Sapporo virus. Natural hosts for the virus are humans and swine. The virus is transmitted through oral/fecal contact.<unk>  most commonly occurs in children and infants and therefore is often spread in nurseries and daycares; however, it has been found in long-term care facilities. This could be due to a lack of personal hygiene and sanitation measures. Symptoms most commonly include diarrhea and vomiting. The<unk>  was initially discovered in an outbreak of gastroenteritis in an orphanage in Sapporo, Japan, 1977.
Sapovirus
Poliovirus
Echovirus
Mengovirus
Arbovirus
Human bocavirus
Coronavirus 
Coronavirus