Hepatitis B is a virus that attacks the liver, causing it to become inflamed and diseased. It is estimated that around 800 million people worldwide are infected with the virus, and another 300 million are carriers. Hepatitis B immunoglobulin is a treatment derived from the blood plasma of donors who have high antibody levels of the hepatitis B antigen. It contains immunoglobulin that belongs to a special class of antibodies capable of triggering a powerful immune reaction, thus preventing infection after a person comes in contact with blood or other material suspected of being infected with the hepatitis B virus.
Although a person may have no symptoms, it is still possible for him to pass Hepatitis B to others. It can be passed on during sexual contact with an infected partner, from an infected mother to her newborn during childbirth, and by intravenous drug use, particularly when needles are being shared. Infection as a result of tattooing or piercing also can occur if the instruments used have not been properly sterilized. It also can be passed via infected blood transfusions and as a result of needle stick injuries.
Hepatitis B immunoglobulin is normally used in combination with the hepatitis B vaccine, which also induces the body's immune system to protect itself from any future exposure to the virus. Research has shown that combining the two is more effective than administering the hepatitis B vaccine alone, because it provides immediate cover and long-lasting protection. Hepatitis B immunoglobulin is made from human blood plasma, so there is a small risk that viruses — not just the hepatitis B virus — and other diseases may be present in the product and passed on to the recipient. To reduce the risk of this happening, strict controls and protocols are applied to the manufacture of the immunoglobulin, and the product is specially treated to remove viruses such as HIV, hepatitis B, hepatitis C and hepatitis A.
A healthcare professional will determine the amount of hepatitis B immunoglobulin required, and individual people may react differently to the same dose of medicine. The immunoglobulin is injected into the muscle and a single dose is usually sufficient for otherwise healthy people. In the case of babies born to carrier mothers, vaccination with hepatitis B immunoglobulin should begin as soon as possible after delivery and no later than 24 hours after birth. If infection has already occurred at the time of immunization, virus multiplication may continue, though severe illness and the development of carrier status may be prevented.