Portal:Viruses/Selected virus/1
Rotavirus is a genus of double-stranded RNA viruses in the family Reoviridae. There are nine species A–I; rotavirus A, the most common, causes over 90% of infections in humans. Rotavirus also infects animals, including livestock. The virus is transmitted by the faecal–oral route, with fewer than 100 virus particles being required for infection. Rotaviruses are stable in the environment and normal sanitary measures fail to protect against them. Effective rotavirus vaccines are the main prevention method.
The virus infects and damages the enterocytes lining the small intestine, causing gastroenteritis (sometimes referred to as "stomach flu," although the virus is not related to influenza). A viral toxin, NSP4, is responsible for some of the pathology. Rotavirus is the most common cause of diarrhoea among infants and young children. Almost every child worldwide has been infected with rotavirus at least once by the age of five. In 2013, 215,000 children under five died from rotavirus infection, mostly in developing countries, and almost two million more become severely ill. Immunity develops with each infection and adults are rarely affected.