Rotavirus infection in adults. Results of a prospective family study.

To study the epidemiologic and clinical features of rotavirus infections, we enrolled 98 families in a prospective study of diarrhea in households with newborn children. Families were seen at three-month intervals and whenever ill. The mean follow-up period was 16.4 months. Rotavirus infections were documented by electron microscopy of feces, indirect fluorescent-antibody assays in serum or both. The 43 infections identified in adults represented an attack rate of 0.17 per adult per year. Ninety-three per cent of these infections occurred from November through May. Seventeen adults had gastrointestinal symptoms, most often diarrhea (in 14) or abdominal cramps (in 11). Rotavirus infections occurred in 36 of 102 adults whose children had rotavirus infection, as compared with four of 86 without infected children (P less than 0.001). Serum rotavirus antibody did not correlate with a reduced risk of infection or symptomatic disease. Rotavirus is a mild but common infection in parents of young children.