Sapovirus

Sapovirus is a genetically diverse genus of single-stranded positive-sense RNA, non-enveloped viruses within the Caliciviridae family. Together with norovirus, sapoviruses 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. Sapovirus 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 sapovirus was initially discovered in an outbreak of gastroenteritis in an orphanage in Sapporo, Japan, 1977. Sapovirus is spread via the fecal/oral route. Infected individuals expel more than 10 9 {displaystyle 10^{9}} particles/gram of feces or vomit. Particles from the infected individual remain viable for years and an infectious dose can be as few as 10 particles. Contamination of work surfaces, hands etc. can cause vast number of new infections. Infection may occur if the particles are inhaled, such as when the particles are aerosolized when those whom are infected vomit, or when the toilet is flushed after an infected individual vomits. Other forms of transmission include the excessive handling of foods by an infected individual (this most commonly occurs in a restaurant setting), consumption of shell fish that lived in waters contaminated with infected fecal matter, and the ingestion of water that has been contaminated. After an incubation period of 1–4 days, signs of illness start to arise. Symptoms of sapovirus are very similar to those of norovirus. The most common symptoms are vomiting and diarrhea; however, additional symptoms may occur. These include: chills, nausea, headache, abdominal cramps, and myalgia—fever is very rare. While patients most frequently start to show symptoms after the 1–4 day incubation period, there have been cases in which an individual is asymptomatic. Although the individual does not show symptoms, they are still capable of spreading the virus through the general mode of transmission, the oral-fecal route.