Part 1, Chapter 12: Manual Appendix IV
Hepatitis B and Hepatitis B Vaccine
IMPORTANT INFORMATION ABOUT HEPATITIS B VIRUS INFECTION AND HEPATITIS B VIRUS VACCINE
WHAT IS HEPATITIS B VIRUS INFECTION?
Hepatitis is an acute inflammation of the liver and may be caused by one of several hepatitis viruses including A, B, or non-A, non-B. The B virus is the most important cause of viral hepatitis and currently Is the only hepatitis virus Infection that is vaccine preventable.
Acute Hepatitis B virus (HBV) Infection is usually mild. Occasionally severe liver damage can follow an acute HBV infection, rarely leading to death. More important is the fact that following an acute HBV infection, five percent to 10 percent of Individuals become permanent carriers of the virus. The virus has been identified in tears and breast milk and has been shown to be transmitted through blood, saliva and semen. Unprotected infants born to mothers who are HBV carriers are at particularly high risk. Eighty-five to 90 percent of Infected infants will become chronic HBV carriers. There are an estimated 700,000 to l,000,000 chronic HBV carriers in the USA today.
The HBV carriers are at risk of serious consequences. The most common serious consequences are severe liver scarring (cirrhosis), chronic active hepatitis and liver cancer (hepatocellular carcinoma). Since there is currently no therapeutic means to eliminate the virus, prevention through active protective immunity is the only effective method available to reduce the risk of infection in individuals who are exposed to the HBV.
Certain population groups are at higher risk of HBV infection. These include health care personnel who are exposed to potentially infected blood, blood products and other body fluids. Also included are Alaska Eskimos, Indochinese and Haitians. Homosexually active males, female prostitutes and users of illicit injectable. drugs are at high risk as well.
The risk of health-care workers acquiring HBV Infection depends on the frequency of exposure to blood or blood products and on the frequency of needlesticks. These risks vary during the training and working career of each individual but are often highest during the professional training period. The risk of HBV infection for hospital personnel can vary both among hospitals and within hospitals. Occupational groups with frequent exposure to blood and/or needles have the highest risk of acquiring HBV infection, including (but not limited to) the following groups: medical technologist, operating room staff, phlebotomists and intravenous therapy nurses, surgeons and pathologists, dental professionals and oncology and dialysis unit staff. Groups shown to be at increased risk in some hospitals include: emergency room staff, nursing personnel, and staff physicians.
HEPATITIS B VIRUS VACCINE:
Hepatitis B virus (HBV) vaccine injected Into the deltoid muscle has been shown to induce protective levels of HBV antibody in more than 90 percent of the individuals who receive the recommended three dose regimen individuals 50 years or older respond slightly less well (77 percent). However, following a three dose regimen the protective efficacy of HBV vaccine has been shown to be 82 percent to 87 percent.
The duration of this protection-and the need for booster doses are not known at this time. Persons who have been previously infected with the HBV will demonstrate HBV antibodies with appropriate serologic tests and are naturally protected. The HBV vaccine administered to persons with naturally acquired HBV antibodies is unnecessary but when given is not harmful.
POSSIBLE VACCINE SIDE EFFECTS:
The HBV vaccine is generally well tolerated. No serious adverse reactions have been attributed to the the HBV vaccine. As with any vaccine, there is the possibility that broader and longer use of the vaccine could reveal rare adverse reactions that to date have not been observed in clinical trails and wide general use. Approximately half of the reported reactions are soreness at the injection side. Occasionally mild side effects such as headache, fatigue and mild gastrointestinal upset have been reported following HBV vaccine.
Persons who may have hypersensitivity to any component of the vaccine should not receive the vaccine. The HBV vaccine should be administered to pregnant women only if clearly needed. The HBV vaccine should be delayed in persons who are experiencing any active infection.