Sapoviruses are gastroenteritis pathogens that belong to the family Caliciviridae which also includes Norovirus, Lagovirus, Vesivirus, and Nebovirus. Sapoviruses are morphologically distinguishable from other gastroenteritis pathogens (norovirus, rotavirus astrovirus, or adenovirus) by their typical “Star of David” surface morphology under the electron microscope. They infect and cause disease in humans of all ages. Sapoviruses have been isolated from several animals (pigs, mink, dogs, sea lions, and bats) as well as from untreated sewage and sewage sludge.
Sapoviruses cause acute gastroenteritis in humans and animals. Major clinical symptoms include diarrhea and vomiting; however, additional constitutional symptoms (nausea, stomach/abdominal cramps, chills, headache, muscle pain) are also frequently reported. Similar to the case for norovirus illness, fever is a rare clinical symptom. Diarrhea usually resolves within 1 week; however, some patients may show symptoms for a longer time (from over a week to up to 20 days). In general, the severity of sapovirus gastroenteritis is milder than that for rotavirus and norovirus. Mortality is rare, but it was reported from outbreaks that occurred in a long-term-care facility for the elderly. Asymptomatic individuals also shed sapovirus in the feces at levels comparable to those shed by individuals with gastroenteritis.1 As many as one third of persons shed the virus before the onset of illness, and peak fecal virus shedding may occur after gastroenteritis symptoms have resolved.2
The primary route of transmission of noroviruses is fecal-oral, or through contaminated food or water, although airborne transmission also occurs. Infection occurs year round but is more common during the colder months.
- Comprehensive Review of Human Sapoviruses
Tomoichiro Oka,corresponding authora,b,* Qiuhong Wang,corresponding authorb,* Kazuhiko Katayama,a,* and Linda J. Saifb,*
- Epidemiology of Acute Gastroenteritis Outbreaks Caused by Human Calicivirus (Norovirus and Sapovirus) in Catalonia: A Two Year Prospective Study, 2010-2011. Nuria Torner,#1,2,3,* Ana Martinez,1,2,‡ Sonia Broner,#2 Antonio Moreno,4,‡ Neus Camps,1,‡ Angela Domínguez,#2,3 and Working Group for the Study of Acute Viral Gastroenteritis Outbreaks in Catalonia PLoS One. 2016; 11(4): e0152503.