Efficacy of post-exposure prophylaxis with hepatitis B immunoglobulin in Norway.

The efficacy of hepatitis B immunoglobulin (HBIG) in preventing infection by hepatitis B virus (HBV) after exposure to blood or blood-containing secretions that carried hepatitis B surface antigen (HBsAg), was studied in an uncontrolled trial in Norway from 1976-1983. Of the 177 HBIG recipients, followed up for 5-24 months, 166 were exposed by needle-stick, splash on mucous membranes or open wounds, sexual contact or medical investigation. With few exceptions, this group was given a single injection of 1250 IU of antibody to HBsAg (anti-HBs) within 7 days after exposure. One person developed clinical hepatitis B (HB) of short duration and two others developed anti-HBs. Six infants with perinatal exposure were injected with three or four doses of about 1250 IU anti-HBs at intervals of 2-3 months. The first dose was given immediately after birth. One child developed clinical HB at the age of 14 months and recovered. Of five patients exposed by blood transfusion, four developed clinical HB; the fifth apparently developed passive-active immunity. One of the four probably became an HBsAg carrier. These patients, except the one without clearance of HBsAg, received one to seven doses of HBIG within 2 days after exposure. Administration of HBIG after needle-stick and similar types of exposure, as well as administration to infants at risk of contracting HB, seems to be of great value.