Prevalence of antibodies to astrovirus types 1 and 3 in children and adolescents in Norfolk, Virginia

Objective, To determine the prevalence of antibody to human astrovirus types 1 (HAstV-1) and 3 (HAstV-3) in children, Methods, Sera from children hospitalized in Norfolk, VA, for noninfectious conditions were collected for a 1-month period every 6 months from 1993 to 1996 and tested by enzyme immunoassay for antibody to HAstV-1 and HAstV-3 with the use of baculovirus-expressed recombinant capsid proteins as antigens, Results. The seroprevalence of 393 infants and children to HAstV-1 decreased from 67% in infants <3 months of age to 7% by 6 to 8 months of age, consistent with loss of transplacental antibodies. Children acquired HAstV-1 antibody with a peak prevalence of 94% at 6 to 9 years of age (P < 0.001). Antibodies to HAstV-3 exhibited a lower prevalence, with 26% positive at <3 months, 0% at 6 to 11 months and 42% by 6 to 9 years of age. HAstV-1 seroprevalence in children 0 to 2 months of age decreased from 89% in November, 1993, to 40% in November, 1996 (P = 0.009), Conclusions. Astrovirus type-specific antibody prevalence can be measured by baculovirus-expressed capsid antigens in an enzyme immunoassay. Children developed antibody to RAstV-1 (94%) and to HAstV-3 (42%) by 6 to 9 years of age indicating frequent exposure to these enteric viruses in infancy and early childhood.