title: Humoral immunity patterns based on antibody reactivity to rotavirus antigens in Brazilian children under 5 years of age.
abstract: The age distribution of antibody to simian rotavirus (SA-11) was studied in serum specimens obtained from 399 children aged to 5 years and living in the city of Recife (PE), located in the north eastern region of Brazil. Sera were examined for group-specific rotavirus antibody using a blocking enzyme immunoassay (bELISA) and a hemagglutination inhibition antibody (HIA) test, and for anti-VP2, anti-VP4, anti-VP6, and anti-VP7 antibodies using an immunoblotting assay (IBA). Antibody prevalence was similar in all bELISA and HIA assays, showing a steep rise in the 6-to 17-month-old age groups. The results indicate early acquisition of antibody to rotavirus. The majority of children aged 2 to 4 years had bELISA (50% to 60%) and HIA (70% to 81%) antibodies. There was an association in prevalence data obtained by HIA and bELISA with immunoblotting (IBA), revealing four serologic profiles. Children with profiles I and II (60%) respectively had HAI and ELISA antibody or HAI antibody alone and all had immunoprotective antibodies to VP4 and/or VP7. These children were regarded as "immune," resembling convalescent patients with a rotavirus infection. Children with profile III (4%) had no HIA antibody and only non-protective anti-VP6 and/or VP7 antibody, and were considered to be "partially immune." Children with profile IV (36%) had no detectable antibody and were classified as "nonimmune." These children should be considered to be susceptible to rotavirus infection, with the risk of developing clinically severe diarrhea.
authors.affiliation: Department of Tropical Medicine, University of Pernambuco, Recife, Brazil.
authors.forename: G P
authors.initials: GP
authors.lastname: Andrade
authors.forename: L R
authors.initials: LR
authors.lastname: Lima
authors.forename: S
authors.initials: S
authors.lastname: Hoshino-Shimizu
authors.forename: M I
authors.initials: MI
authors.lastname: Oliveira
authors.forename: R Z
authors.initials: RZ
authors.lastname: Mendonça
authors.forename: C M
authors.initials: CM
authors.lastname: Hársi
authors.forename: K E
authors.initials: KE
authors.lastname: Stewien
mesh_terms: D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D000917:Antibody Formation; D000956:Antigens, Viral / Q000276:immunology*; D001938:Brazil; D002213:Capsid / Q000276:immunology; D036022:Capsid Proteins; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005500:Follow-Up Studies; D005759:Gastroenteritis / Q000276:immunology / Q000821:virology*; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D015151:Immunoblotting; D007223:Infant; D007231:Infant, Newborn; D012401:Rotavirus / Q000276:immunology / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000097:blood / Q000276:immunology / Q000821:virology*
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; C442545:VP2 protein, Rotavirus; C060339:VP4 protein, Rotavirus; C061332:VP6 protein, Rotavirus; C050779:VP7 protein, Rotavirus