title: Shifts in the rates and levels of antibody to hepatitis A virus associated with hepatitis A infection in children's communities.
abstract: In order to investigate the shift in the rates and levels of antibody to hepatitis A virus, 567 children in 20 isolated groups of five day-care centers were observed over a period of 8 months during which the seasonal rise in hepatitis A morbidity occurs. Increases in the proportion of seropositive ranging from 5 to 37% were demonstrated in 6 groups, and were always associated with the occurrence of either overt or sub-clinical hepatitis A infection. High rates of seropositivity were also noted in the groups in which cases of hepatitis A had been registered prior to the period of observation. In some children with low and medium antibody levels, antibody titres showed further increases after reinfection. A substantial part of children retained low antibody titres during the entire period of observation, and eight previously sero-negative children developed low antibody levels after asymptomatic hepatitis A infections. In one group the spread of hepatitis A infection (clinical and asymptomatic) was prevented by the administration of commercially available immunoglobulin immediately after the discovery of an infected food handler. Passive antibodies were found in previously sero-negative children, and these antibodies dropped to undetectable levels two months after administration.
authors.affiliation: Institute of Poliomyelitis and Viral Encephalitides, USSR Academy of Medical Sciencies, Moscow.
authors.forename: S A
authors.initials: SA
authors.lastname: Prikazchikov
authors.forename: M S
authors.initials: MS
authors.lastname: Balayan
mesh_terms: D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D006506:Hepatitis A / Q000453:epidemiology*; D006508:Hepatitis Antibodies / Q000032:analysis*; D006507:Hepatovirus / Q000276:immunology*; D006801:Humans; D007136:Immunoglobulins / Q000008:administration & dosage; D014586:USSR
chemical_list: D006508:Hepatitis Antibodies; D007136:Immunoglobulins