title: Epidemiology of hepatitis B infection in Liberian infants.
abstract: To provide background for a hepatitis B vaccine efficacy trial, sera were collected from 0- to 4-year-old Liberian infants and their mothers, on two occasions an average of 14.75 months apart, and tested for serological markers of hepatitis B virus infection. The prevalence of the hepatitis B surface antigen (HBsAg) was 2.9% in the 0- to 6-month age group and 23% in infants 3 to 4 years of age. HBsAg persisted for the 14.75-month average follow-up period in 80.8% of the infants tested. The annual incidence of development of HBsAg was 18.9% for infants less than 1 year of age and 13.6% in infants 3 to 4 years of age. Infants born to HBsAg carrier mothers had significantly higher age-specific prevalence and incidence of hepatitis B virus infection. However, it was estimated that only a minor proportion of hepatitis B infections in Liberia are derived by vertical transmission from carrier mothers.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002353:Carrier State; D002675:Child, Preschool; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000276:immunology / Q000635:transmission; D006510:Hepatitis B Antibodies / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology* / Q000276:immunology; D007988:Liberia; D008875:Middle Aged
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens