title: Efficacy and long-term durability of intradermal recombinant hepatitis B virus vaccine among intramuscular vaccine nonresponders: A prospective study in healthcare personnel.
abstract: BACKGROUND
  Data on efficacy, safety, and durability of intradermal vaccine administration in persons who have not responded appropriately to intramuscular administration of hepatitis B virus (HBV) vaccine are relatively scarce.
  
  
  METHODS
  We designed a prospective case series in an urban tertiary care hospital in Israel. The medical records of 4007 healthcare personnel who had worked in the hospital between 1996 and 2006 were examined and those with an unsatisfactory level (<10 mIU/ml) of hepatitis B surface antibody (HBsAb) following two courses of a three-dose intramuscular HBV vaccine ("nonresponders") were identified. Nonresponders were vaccinated with three doses of 5 µg of intradermal recombinant hepatitis B surface antigen-based vaccine at weeks 0, 2, and 4. Level of HBsAb was determined 4 weeks after the last dose, and an additional dose was administered as needed. HBsAb level was again determined 24 weeks after the final vaccine dose to assess late immune reactivity and long-term durability of the vaccine. Vaccine safety was assessed at each vaccination and testing session.
  
  
  RESULTS
  Twenty-seven subjects were included in the study, and 21 completed the study. The proportion of subjects with satisfactory HBsAb level at 4 weeks after the last administered dose was 70.3% (19/27). The proportion of subjects with sustained immune response at 24 weeks was 62.9% (17/27) according to intention-to-treat analysis and 80.9% (17/21) according to per protocol analysis. There were no reports of adverse events in response to the administration of the vaccine.
  
  
  CONCLUSIONS
  Intradermal administration of HBV vaccine offers an efficient, safe, and durable option for intramuscular vaccine nonresponders and represents a means to optimize utilization of the widespread HBs antigen-based vaccine formulation.
authors.affiliation: Department of Medicine B, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Or
authors.identifier: http://orcid.org/0000-0001-9856-627X
authors.initials: O
authors.lastname: Kalchiem-Dekel
authors.affiliation: Department of Medicine B, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Daniel
authors.initials: D
authors.lastname: Grupel
authors.affiliation: Infection Control Unit, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Lea
authors.initials: L
authors.lastname: Bouchnik
authors.affiliation: Department of Medicine B, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Sikuler
authors.affiliation: Department of Medicine B, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|Institute of Gastroenterology and Hepatology, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Gil
authors.initials: G
authors.lastname: Ben-Yakov
mesh_terms: D005260:Female; D006282:Health Personnel; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D007273:Injections, Intramuscular; D007279:Injections, Subcutaneous; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012449:Safety; D013997:Time Factors; D014614:Vaccines, Synthetic / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic
keywords: healthcare personnel; intradermal; intramuscular; vaccine; viral hepatitis B