title: Immune response to second vaccination series of hepatitis B virus among booster dose non-responders.
abstract: OBJECTIVE
  To evaluate the response to second vaccination series among post-booster sero-negative children who had previously received compulsory HBV vaccination.
  
  
  METHODS
  After given a booster dose to 1070 children, 103 of them failed to generate anamnestic response (anti-HBs <10 IU/L). Only 91/103 children received additional two doses of recombinant HBV vaccine (i.e. 2(nd) vaccination series) after 1 and 6 months post-booster. Blood sample was withdrawn aseptically one month later for quantitative assessment of anti-HBs to detect development of protective immune response (≥10 IU/L). Immunological vaccination failure was assigned to children who did not develop protective immune response after 2(nd) vaccination series.
  
  
  RESULTS
  Protective immune response was detected among 84/91 children (92.3%). While 7/91 (7.7%) whose age were ≥10 years did not respond and had post-booster undetectable anti-HBs. About 80% of children with post-booster detectable anti-HBs showed significant protective immune response (anti-HBs ≥100 IU/L) and higher GMT (299.1 ± 3.6 IU/L) compared to those with undetectable 60% and 106.2 ± 12.9 IU/L respectively (P<0.05). No significant difference was detected as regards gender or residence, P>0.05. All children with history of rheumatic fever (7 children) or diabetes mellitus (1 child) developed immune response after 2(nd) vaccination series.
  
  
  CONCLUSIONS
  A booster dose of HB vaccine may be unable to induce sufficient immunological response in children who had undetectable anti-HBs titers. Revaccination for non-responders is an important procedure to increase HBV protection rate.
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt. Electronic address: salamaiman@yahoo.com.
authors.forename: Iman I
authors.initials: II
authors.lastname: Salama
authors.affiliation: Pediatrics, National Research Center, Cairo, Egypt.
authors.forename: Samia M
authors.initials: SM
authors.lastname: Sami
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Somaia I
authors.initials: SI
authors.lastname: Salama
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Thanaa Mahmoud
authors.initials: TM
authors.lastname: Rabah
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Lobna Ahmed
authors.initials: LA
authors.lastname: El Etreby
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Amany T
authors.initials: AT
authors.lastname: Abdel Hamid
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Dalia
authors.initials: D
authors.lastname: Elmosalami
authors.affiliation: Community Medicine, National Research Center, Cairo, Egypt.
authors.forename: Hazem
authors.initials: H
authors.lastname: El Hariri
authors.affiliation: Microbiology & Immunology, Faculty of Medicine (for Girls), Al Azhar University, Cairo, Egypt.
authors.forename: Zeinab N
authors.initials: ZN
authors.lastname: Said
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control; D006510:Hepatitis B Antibodies / Q000097:blood*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000627:therapeutic use; D006801:Humans; D007117:Immunization, Secondary; D007156:Immunologic Memory; D007223:Infant; D008297:Male; D011446:Prospective Studies; D014611:Vaccination / Q000379:methods; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic
keywords: Egypt; HBV; Immunity; Second vaccination series