Enzootic bovine rotavirus is not a source of infection in Panamanian cattle ranchers and their families.

Vaccination of humans against rotavirus (RV) diarrhea may be accomplished by oral immunization with attenuated animal strains known to be antigenically very similar to human strains. To define better the degree of infectivity in nature of these animal strains for humans, we conducted surveillance for RV infection/diarrhea in 180 farm workers, their 161 family contacts, and the 566 animals (512 cattle, 35 pigs, and 19 sheep) on 14 farms in rural Panama. No correlation between the high infection rates in farm workers (72%) and their family contacts (78%) and in cattle (56%) could be demonstrated. Heads of families with four or more children with RV infection experienced a twofold greater rate of RV infection compared with heads of families of similar size without RV infection. Despite the close similarity between human and bovine RV, in Panama intrafamilial (particularly child-to-child or child-to-parent) rather than interspecies transmission appeared to be the most important route for the spread of this highly infectious virus.