Abstract
The spread of rotavirus infection was studied over four weeks in a sample of 28 families exposed to a child with rotavirus infection. The results showed a high incidence of intrafamilial infection, with 46% of members of these families developing rotavirus infections compared with none in another series of 18 families. Children in the families with an index case were more frequently affected than adults: 75% of the children developed rotavirus infection but only 33% of the adults. Children tended to suffer the infection in a more severe form. Intrafamily contact is clearly important in transmitting rotavirus infection, and preventive measures should aim at reducing the likelihood of such cross infection.