what is rotavirus?
It is a genus of double-stranded RNA viruses in the family "Reoviridae".
Rotavirus
Rotavirus is a genus of double-stranded RNA viruses in the family "Reoviridae". 
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Rotavirus [SEP] Introduction
Rotavirus is a genus of double-stranded RNA viruses in the family "Reoviridae". Rotaviruses are the most common cause of diarrhoeal disease among infants and young children. Nearly every child in the world is infected with a rotavirus at least once by the age of five. Immunity develops with each infection, so subsequent infections are less severe; adults are rarely affected. There are ten species of the genus, referred to as A, B, C, D, E, F, G, H, I and J. "Rotavirus A", the most common species, causes more than 90% of rotavirus infections in humans. The virus is transmitted by the faecal-oral route.