Rotavirus Gastroenteritis is a virus that infects the bowels and is most commonly found in children and is a genus of double-stranded RNA virus in the family Reoviridae. It is estimated that every child will have at least one rotavirus infection before the age of five. Rotavirus A, the most common, causes more than 90% of infections in humans. Repeat infections with different viral strains are possible, and most children have several episodes of rotavirus infection in the first years of life.