title: Hepatitis A vaccine versus immune globulin for postexposure prophylaxis.
abstract: BACKGROUND
  Hepatitis A vaccine administered to persons after exposure to the hepatitis A virus has not been compared directly with immune globulin, which is known to be highly effective in preventing hepatitis A when given within 2 weeks after exposure to the virus.
  
  
  METHODS
  We randomly assigned household and day-care contacts, 2 to 40 years of age, in Almaty, Kazakhstan, to receive one standard age-appropriate dose of hepatitis A vaccine or immune globulin within 14 days after exposure to patients with hepatitis A. Instances of laboratory-confirmed, symptomatic hepatitis A infection occurring between 15 and 56 days after exposure were then assessed during active follow-up of all susceptible contacts.
  
  
  RESULTS
  Of 4524 contacts who underwent randomization, 1414 (31%) were susceptible to hepatitis A virus and 1090 were eligible for the per-protocol analysis. Among these contacts, 568 received hepatitis A vaccine and 522 received immune globulin. Most contacts were children (average age, 12 years), and most received prophylaxis during the second week after exposure (average interval after exposure, 10 days). The baseline characteristics of the contacts were similar in the two groups. Symptomatic infection with hepatitis A virus was confirmed in 25 contacts receiving vaccine (4.4%) and in 17 contacts receiving immune globulin (3.3%) (relative risk, 1.35; 95% confidence interval, 0.70 to 2.67).
  
  
  CONCLUSIONS
  Low rates of hepatitis A in both groups indicate that hepatitis A vaccine and immune globulin provided good protection after exposure. Although the study's prespecified criterion for noninferiority was met, the slightly higher rates of hepatitis A among vaccine recipients may indicate a true modest difference in efficacy and might be clinically meaningful in some settings. Vaccine has other advantages, including long-term protection, and it may be a reasonable alternative to immune globulin for postexposure prophylaxis in many situations. (ClinicalTrials.gov number, NCT00139139 [ClinicalTrials.gov].).
authors.affiliation: University of Michigan, Ann Arbor, USA.
authors.forename: John C
authors.initials: JC
authors.lastname: Victor
authors.forename: Arnold S
authors.initials: AS
authors.lastname: Monto
authors.forename: Tatiyana Y
authors.initials: TY
authors.lastname: Surdina
authors.forename: Saida Z
authors.initials: SZ
authors.lastname: Suleimenova
authors.forename: Gilberto
authors.initials: G
authors.lastname: Vaughan
authors.forename: Omana V
authors.initials: OV
authors.lastname: Nainan
authors.forename: Michael O
authors.initials: MO
authors.lastname: Favorov
authors.forename: Harold S
authors.initials: HS
authors.lastname: Margolis
authors.forename: Beth P
authors.initials: BP
authors.lastname: Bell
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006506:Hepatitis A / Q000276:immunology / Q000517:prevention & control*; D022362:Hepatitis A Vaccines; D017957:Hepatitis A Virus, Human / Q000276:immunology*; D006508:Hepatitis Antibodies / Q000097:blood; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007136:Immunoglobulins / Q000627:therapeutic use*; D007223:Infant; D008297:Male; D008875:Middle Aged
chemical_list: D022362:Hepatitis A Vaccines; D006508:Hepatitis Antibodies; D007075:Immunoglobulin M; D007136:Immunoglobulins