The Tecumseh Study. XV: Rotavirus infection and pathogenicity.

Rotavirus infection and associated symptoms were studied prospectively from 1976 through 1981 in a 10% sample of families in Tecumseh, Michigan. Infection was determined using an antibody enzyme-linked immunosorbent assay (ELISA) method designed for use with large numbers of sera collected semiannually. Illness was identified from symptoms ascertained weekly by telephone. Risks of infection during a rotavirus season varied from 4.8% in 1978 to 9.2% in 1980. Risks were 20.6% in the under two years age group and decreased progressively with age to 3.6% in individuals aged 45 years or over. Preschool children accounted for less than 20% of the infections in the population of reference. Infection was associated with diarrhea in the first two years of life and with both diarrhea and vomiting later in life. There was no evidence for association of rotavirus infection with a gastrointestinal-respiratory syndrome. The pathogenicity of infection, the protectiveness of antibody, and the socioeconomic correlates of infection showed marked changes from year to year. In 1978, there was a dramatically higher pathogenicity and a greater protectiveness of ELISA measured antibody than in other years. There was also a dramatic reversal in the socioeconomic relations of infection from 1977 to 1978. Taken together, these findings suggest that different rotaviruses might have predominated in these years.