WHAT IS HEPATITIS B?
Hepatitis B is a virus that can infect the liver and cause damage. It is estimated that there are 80,000 new cases of hepatitis B each year in the United States. The virus can persist in the body of some individuals. It is estimated that 1.25 million Americans are chronic carriers of the hepatitis B virus.
HOW IS THE HEPATITIS B VIRUS TRANSMITTED?
The hepatitis B virus is spread by exposure to infected body fluids. The virus can be found in blood, saliva, semen, vaginal secretions and breast milk of infected individuals. Hepatitis B is most commonly transmitted by sharing contaminated needles (such as in intravenous drug abuse), sexual intercourse, or from an infected mother to her baby at the time of birth. Potential blood donors are carefully tested for the hepatitis B virus and excluded if they test positive. Therefore, blood transfusions do not cause hepatitis B infection.
HOW IS HEPATITIS B DIAGNOSED?
Hepatitis B can be diagnosed through a series of blood tests. There are different parts of the hepatitis B virus that can be looked for. The basic part of the virus named Hepatitis B surface antigen (sometimes abbreviated HBsAg ) is the initial blood test to determine if the virus is present. Other parts of the virus that can be tested for are called core and envelope (known as c and e ) and the hepatitis B DNA. By performing this panel of blood tests one can determine if the hepatitis B virus is a recent or long-standing infection and also whether or not the virus is active.
WHAT HAPPENS TO A PERSON THAT IS INFECTED WITH THE HEPATITIS B VIRUS?
Some patients infected with Hepatitis B do not have significant symptoms. There is a period of time between the time a patient contracts the virus and the onset of symptoms. This is called the incubation period and ranges from 1 to 3 months. Symptoms associated with Hepatitis B infection can include muscle and joint aches, decreased appetite, nausea, vomiting, right upper abdominal pain, fever and weakness. Other patients with more significant irritation of the liver may have jaundice with yellowing of the skin and eyes, dark urine and light-colored stools. Most adult patients (95%) will clear the Hepatitis B virus and not have any damage to the liver. If a person does not clear the virus after 6 months, he or she is considered to be a carrier or to have chronic Hepatitis B. Hepatitis B virus carriers are patients with no symptoms who only have the inactive part of the virus in their blood (HBsAg) and normal liver blood tests. A patient with chronic Hepatitis B can have both the inactive (HBsAg) and active (e and DNA) parts of the virus in their blood that can cause ongoing liver damage. Patients with chronic hepatitis B can go on to develop scarring of the liver known as cirrhosis, liver failure, or liver cancer. These patients may need to be considered for liver transplantation.
HOW IS HEPATITIS B INFECTION TREATED?
The most effective treatment for hepatitis B is to prevent it. If a patient is not able to eliminate the virus after 6 months and has ongoing active virus in their blood he or she may be a candidate for treatment. Currently approved therapies for chronic Hepatitis B are lamivudine (Epivir-HBV), adefovir (Hepsera) and interferon. The goal of these therapies is to make the Hepatitis B virus inactive. Rarely the virus is eliminated completely from the blood. The first two medications are given orally and are tolerated well. Interferon is a medication given as an injection under the skin at least weekly for 3 to 6 months. Interferon has many side effects including flu-like symptoms, irritability, depression and decreased blood counts. There are pros and cons to using these medications. The decision is based on a variety of factors including how long a person has had the infection and blood test results.
HOW CAN HEPATITIS B INFECTION BE PREVENTED?
There is a safe vaccine to protect a person against Hepatitis B. The vaccination is given as a series of three muscle injections over 6 months. It is now part of the routine vaccinations given to newborns. It is also recommended that health care personnel, hemodialysis patients, chronic liver disease patients, people with multiple sexual partners, injection drug users, and household or sexual contacts of persons with chronic Hepatitis B infection be vaccinated. The vaccination is safe and effective in preventing Hepatitis B infection.