Since most of the reoviruses are caused by contact with an animal or arthropod vector, the main avenue for prevention is to avoid contact with these vectors. If in the areas where the vectors are found, insect repellent should be worn and so forth.
Rotavirus infection is transmitted via the fecal-oral route, and thus through contact with feces. Ways to prevent infection include: emphasis on hygiene, frequent hand washing, disinfection of household areas, and the proper disposal of sewage, diapers, etc. The sanitation levels worldwide need to be improved as part of a prevention plan for rotavirus.
A great deal of work has been done to develop a rotavirus vaccine. The vaccine that is closest to becoming liscenced is a live, attenuated vaccine that is administered orally. It is created from rhesus monkey rotavirus and is genetically manipulated to lose virulence and is called the rhesus rotavirus tetravalent vaccine (RRV-TV). It has been shown to be roughly 80% effective in most populations, but there is evidence that in the developing world (where the vaccine is most needed), RRV-TV is much less effective, to the tune of only 50-60%. Another problem with the vaccine is timing. It must be given at the right age, when the chid is still a newborn, but not too close to birth when cross-reacting antibodies with the mother are possible. The vaccine also must be administered before the child gets the disease, which in most cases is very young. In terms of cost effectiveness, a vaccine initiative might lose out to an oral rehydration therapy program, which would be less expensive. Indeed, ORT exists as a very real possiblity for halting rotavirus deaths. Nevertheless, the increasing chance for an effective rotavirus vaccine promises a vast decrease in infant mortality as well.
For more information on the rotavirus vaccine and its implications, try Expanded Programme on Immunization's Rotavirus Vaccine page.
Also, the World Health Organization has an informative page.