Hepatitis A vaccine versus immunoglobulin for post-exposure prophylaxis

been recommended for prophylaxis of HA in post-exposure and pre-exposure settings, respectively. This randomized, double-blind, active-control, non-inferiority trial compared the efficacy of HA vaccine and IG in preventing HA when given within 2 weeks after exposure. It was carried out in Almaty, Kazakhstan, an area of intermediate HA endemicity, with day 1 of exposure being defined as the day of onset of first symptom in the index patient. Household and daycare contacts of confirmed index patients with HA were enrolled if they were between 2 and 40 years of age, and had no history of HA or vaccination, or of liver disease. All contacts had a blood specimen drawn at baseline to test for susceptibility to HA (negative for total antibody against hepatitis A virus [HAV]) and simultaneously randomized to receive either IG (0.02 ml/kg) or vaccine (single dose; VAQTA, Merck) intramuscularly. Analysis was done only for susceptible individuals. Separate randomization was done fo