Hepatitis B is one of several types of hepatitis (liver inflammation) caused by a virus. Among the ways in which the virus can be spread are contact with infected blood and sex with an infected person. It can also be transmitted from an infected mother to her child during childbirth. Many acute cases of this virus get better on their own, but chronic cases often require treatment with medications.
Hepatitis B is a disease of the liver caused by a virus (specifically, the hepatitis B virus). Most people who get it can get rid of the virus on their own, but others can develop chronic (or life-long) hepatitis B.
It is estimated that 350 million individuals worldwide are infected with the virus, which causes 620,000 deaths worldwide each year. According to the Centers for Disease Control (CDC), approximately 46,000 new cases of hepatitis B occurred in the United States in 2006.
Besides hepatitis B, there are several other types of viral hepatitis, including hepatitis A, C, D, E, and G.
The cause of hepatitis B is an infection with the hepatitis B virus (HBV). This is a DNA virus that belongs to the genus Orthohepadnavirus of the Hepadnaviridae family. The virus is passed from person to person through blood, semen or other body fluids. When HBV enters your liver, it invades the liver cells and begins to multiply. This causes inflammation in the liver and leads to the signs and symptoms of hepatitis B infection.
Common ways HBV is transmitted include:
Sexual contact. You may become infected through sexual contact with an infected person whose blood, saliva, semen or vaginal secretions enter your body.
Sharing of needles. HBV is easily transmitted through needles and syringes contaminated with infected blood. Sharing intravenous (IV) drug paraphernalia puts you at high risk of hepatitis B.
Accidental needle sticks. Hepatitis B is a concern for health care workers and anyone else who comes in contact with human blood.
Mother to child. Pregnant women infected with HBV can pass the virus to their babies during childbirth.
Hepatitis B is not spread by air, food, water, breastfeeding, casual contact in an office setting, kissing, hugging, coughing, sneezing, or sharing eating utensils or drinking glasses.
Hepatitis B infection may be either short-lived (acute hepatitis B) or long lasting (chronic hepatitis B).
Acute hepatitis B infection lasts less than six months. If the disease is acute, your immune system is usually able to clear the virus from your body, and you should recover completely within a few months. Most people who acquire hepatitis B as adults have an acute infection.
Chronic hepatitis B infection lasts six months or longer. When your immune system can't fight off the virus, hepatitis B infection may become lifelong, possibly leading to serious illnesses such as cirrhosis and liver cancer. Most infants infected with HBV at birth and many children infected between 1 and 5 years of age become chronically infected. Chronic infection may go undetected for decades until a person becomes seriously ill from liver disease. People with the chronic type can infect others and are at an increased risk of serious liver disease, including cirrhosis and liver cancer. In the United States, an estimated 1.25 million people are chronically infected with HBV.
The hepatitis B virus is spread through infected bodily fluids. Among these bodily fluids are infected blood and blood products. Exposure to infected blood or blood products can occur through working in a laboratory or a dialysis unit, through infected needles used for tattoos or body piercing, or through sharing drug needles. In a few cases, people have been infected with hepatitis B by sharing objects that may have a tiny amount of blood on them, such as a toothbrush, razor, or tools used for manicures.
Hepatitis B is also spread through contact with other infected bodily fluids, such as semen, vaginal fluids, or saliva. A person cannot get the virus from a kiss or other normal everyday activities, such as hugging or shaking hands.
Your risk of hepatitis B infection is increased if you:
Have sex (fornication, adultery) with more than one person
Have sex with someone who's infected with HBV
Have a sexually transmitted infection such as gonorrhea or chlamydia
Are a man who has unnatural sexual contact with other men
Share needles during intravenous (IV) drug use
Share a household with someone who has a chronic HBV infection
Have a job that exposes you to human blood
Receive hemodialysis for end-stage kidney (renal) disease
Travel to regions with high infection rates of HBV, such as Africa, Central and Southeast Asia, and Eastern Europe
When a person becomes infected with the hepatitis B virus (HBV), the virus begins to multiply within the liver cells. As more and more of the hepatitis B virus is made in the liver cells, they can become damaged and may even die.
After 4 to 12 weeks (on average), hepatitis B symptoms can begin. This period between hepatitis B transmission and the start of hepatitis B symptoms is called the "hepatitis B incubation period." The hepatitis B incubation period can be as short as 30 days or as long as 180 days. This incubation period is dependent of the number of virus particles a person is exposed to. Infection with very few particles results in a longer incubation period.
Some hepatitis B symptoms that are especially common in the early stages of the disease include fatigue, diarrhea, nausea or vomiting, and a low-grade fever. Most people with hepatitis B gradually get better within a couple of months. For some people, however, the body is unable to kill the hepatitis B virus. These people develop chronic hepatitis B. A person with chronic hepatitis B may develop cirrhosis, which can cause signs and symptoms such as weakness, nausea, weight loss, and loss of appetite.
When a person becomes infected with the hepatitis B virus (HBV), the virus begins to multiply within the liver. Thirty to 180 days later, a person may develop symptoms of hepatitis B.
However, not everyone infected with the hepatitis B virus will actually have symptoms. Also, some of the people who do develop symptoms will have only very mild symptoms. In fact, about 30 percent of people with this disease will have no symptoms of hepatitis B. You can look and feel perfectly healthy, yet still be infected with the disease and infect others.
Infants and children are more likely to have mild symptoms or no symptoms at all. People over the age of 50 are most likely to have more severe symptoms.
For a person with hepatitis B, symptoms (especially early symptoms) may include one or several of the following:
Fatigue
Excessive tiredness
Not feeling very hungry
Nausea or vomiting
Diarrhea
A low-grade fever
Muscle pain
Joint pain
Sore throat
Mild abdominal pain (or stomach pain)
Dark urine
Light-colored stool.
Oftentimes, these early symptoms may be confused with those commonly seen with the stomach flu.
Jaundice (yellowing of the skin or the whites of the eyes) usually occurs several days after early symptoms of hepatitis B first appear. However, it may occur up to two weeks after symptoms begin. At this point, early symptoms tend to improve; but other new symptoms may appear, such as abdominal pain (or stomach pain) on the right side.
The overall rate of death from a hepatitis B infection is 1 percent. Loss of life is more common in older people infected with the hepatitis B virus. When someone dies from a hepatitis B infection, it is most often because of a complication known as fulminant hepatitis, which is a condition that results in liver failure. Besides older individuals, people who are at an increased risk of fulminant hepatitis include those with severe liver disease (cirrhosis) and those who have had a liver transplant.
For most people, acute hepatitis B symptoms gradually get better within a couple of months. These people will have no long-lasting liver damage and will recover completely. Yet, for some people, the body is not able to completely get rid of the virus. These people end up having a long-term liver infection. This is known as chronic hepatitis B.
Acute hepatitis B will lead to a chronic (long-term) liver infection in 30 percent to 90 percent of people who were infected as infants or children and 6 percent to 10 percent of those infected as adolescents and adults. Chronic infection can lead to chronic liver disease, liver scarring, and liver cancer.
The hepatitis B virus (or HBV) can affect a person with chronic hepatitis B much differently than it would affect someone else. For example, some people have very bad symptoms of hepatitis B and cirrhosis after many years of having the disease, while others have very few scars.
For some people with chronic hepatitis B, the scarring within the liver can get bad and can interfere with, or even prevent, blood from flowing freely through the liver. This makes it harder for the liver to do its job. As the hepatitis continues, more scars are formed and can begin to join together. When many of these scars form together, it is called cirrhosis.
Cirrhosis means that large areas of the liver have become very badly scarred -- usually permanently. This causes the liver to shrink and harden.
There are a number of cirrhosis symptoms that can occur as a result of chronic hepatitis B. Some of these symptoms include:
Exhaustion
Fatigue
Jaundice
Loss of appetite
Nausea
Weakness
Weight loss
Abdominal pain (or stomach pain)
Spider-like blood vessels (spider angiomas) that develop on the skin.
As the liver continues to be damaged and scarred, it may stop performing one or more of its normal functions. For example, it may stop cleaning harmful wastes, toxins, and drugs from the blood. It may also stop making enough of the proteins your body needs to function properly. This is called liver failure.
It is possible that before liver failure develops, people with hepatitis B may not even know that their liver is being damaged. They may not have any symptoms of hepatitis B or notice any physical changes to their body.
However, when the liver becomes badly damaged with cirrhosis and liver failure occurs, several late hepatitis B symptoms can begin to appear, including:
Fluid build-up in the stomach area and legs
Bleeding in the intestines
Slowing of mental function
Bruising or bleeding that occurs very easily
Itchy skin
Personality changes
Coma or death.
When liver failure occurs in a person with hepatitis B, he or she may also develop:
Bleeding in the stomach and esophagus (known as varices)
Insulin resistance
Diabetes
High blood pressure within the liver (portal hypertension)
Sensitivity to medication
Gallstones.
Specific treatment usually isn't necessary for short-term cases of hepatitis B. But for those who develop a chronic condition, treatment may include medications such as alpha interferon and lamivudine. These medications work best in people with high liver enzymes and low levels of the virus in their blood. Staying healthy during hepatitis B treatment involves getting enough calories and exercise.
There are two types of hepatitis B -- acute (recently acquired) hepatitis B and chronic (lifelong) hepatitis B. Treatment differs for each type.
For acute hepatitis B, there are no specific medicines that can cure the disease. Therefore, treatment is focused on dealing with any symptoms or complications that may occur. This is known as supportive care. Even without specialized treatment for acute hepatitis B, however, most people recover completely within a few months.
Although many people who are exposed to hepatitis B will be able to get rid of the virus, some people can develop a chronic condition. This may lead to liver damage, liver cancer, and death. In these cases, specific medicines are available to help slow down liver damage and possibly prevent associated complications.
If you've been diagnosed with chronic hepatitis B infection, your doctor may recommend:
Antiviral medications. Antiviral medications help fight the virus and slow its ability to damage your liver. Several medications are available. Your doctor can suggest which medications may be most appropriate for you.
Liver transplant. If your liver has been severely damaged, a liver transplant may be an option. During a liver transplant, the surgeon removes your damaged liver and replaces it with a healthy liver. Most transplanted livers come from deceased donors, though a small number come from living donors.
Even if a person develops a chronic infection, treating hepatitis B with medicine is not right for everyone. Medicines often work best for people with:
Low levels of the hepatitis B virus (HBV) in the blood
High liver enzymes
A liver biopsy that shows moderate disease activity and fibrosis.
The U.S. Food and Drug Administration (FDA) has approved six drugs for the treatment of chronic hepatitis B. These include:
Alpha interferon
Pegylated alpha interferon
Lamivudine (Epivir-HBV)
Adeforvir dipivoxil (Hepsera)
Entecavir (Baraclude)
Telbivudine (Tyzeka).
These medicines differ in a number of respects. While some of these medicines are given by injection, others are taken by mouth. Some other differences include:
How long they are taken
How effective they are in clearing the virus and stopping any liver damage
Whether they are approved for use in children as well as adults
Side effects
Interactions with other medicines
Whether they increase the risk of a severe and sudden worsening of hepatitis B symptoms after stopping the medicine.
If you are taking any of these medicines, you should stop treatment only after a careful discussion with your doctor. These drugs should not be used during pregnancy.
The goals of chronic hepatitis B treatment are to:
Suppress the virus indefinitely
End any active liver disease.
People with HBeAg-positive chronic hepatitis who have a substantial decrease in the level of HBV DNA (the genetic material of the virus) and a loss of HBeAg at the end of therapy are said to have had a virologic response to treatment. A sustained virological response (SVR) is one that continues for 6 to 12 months after therapy ends. People who have a sustained loss of HBsAg are deemed to have a complete response to antiviral therapy, but this does not happen often.
The response rate to alpha interferon or lamivudine is above 50 percent in people whose ALT levels (an enzyme found in liver cells) are greater than five times the upper limit of normal. The response rate is lower (about 20 to 35 percent) in people with ALT levels two to five times the upper limit of normal. In people with ALT levels less than two times the upper limit of normal, response rates are poor and therapy should be deferred.
Regardless of whether you have acute or chronic hepatitis B, you should take certain steps to stay healthy and avoid hurting your liver -- both as your body is fighting the hepatitis B virus and after treatment has ended. Some of these things include:
Getting enough calories. Many people with hepatitis B -- especially those taking medication -- get nauseous. In order to get enough calories, try eating several small meals throughout the day, instead of three large meals a day. If you feel sick in the morning, try eating some crackers or dry toast before getting out of bed. It may also help to drink lemon water or have a lemon drop.
Getting plenty of rest.
Drinking plenty of fluids. You should try to drink at least 10 to 16 glasses a day of water, clear juices, or other drinks that do not have caffeine in them.
Avoiding medicines that can harm the liver. Talk with your healthcare provider about all of the medicines that you take, including prescription and over-the-counter medicines, as well as vitamins and herbal remedies.
Avoiding alcohol. Alcohol poisons your liver and can cause even more damage to the cells that are already fighting the hepatitis B virus. The exact amount of alcohol that will harm the liver isn't known. Therefore, it's generally recommended that people with hepatitis B avoid alcohol completely.
Exercising regularly. Do light-to-moderate exercise for 30 minutes a day. Walking is one example of an activity that can provide light-to-moderate exercise.
If you've been infected with hepatitis B, take steps to protect others from the virus. For instance:
Take precautions to make sex safer. The only way to protect your marital partner or from your hepatitis B infection is to avoid sexual contact. If you choose to have sex, talk to your partner about the risk of transmitting HBV. Don't use condoms or contraceptives.
Tell people you have had sexual contact with that you have HBV. Let anyone with whom you've had sex with know that you have HBV. They need to be tested and receive medical care if they have the virus. They also need to know their HBV status so that they don't risk infecting others.
Don't share needles or syringes. If you use IV drugs, never share your needles and syringes with anyone.
Don't donate blood or organs. Donating infected blood or organs spreads the virus.
Don't share razor blades or toothbrushes. These items may carry traces of infected blood.
If you're pregnant, tell your doctor you have HBV. That way, your baby can be treated soon after birth.
One herb that continues to attract attention for its touted liver-health properties is milk thistle. Proponents of milk thistle recommend the herb to treat jaundice and other liver disorders. People take milk thistle as a capsule, extract or infusion.
Small studies of milk thistle treatment for liver disease have had mixed results. Many of the studies have been poorly designed, making it difficult for researchers to draw conclusions about the usefulness of milk thistle.
If you're interested in trying milk thistle, discuss the benefits and risks with your doctor.
The hepatitis B vaccine is typically given as a series of three or four injections over a period of six months. You can't get hepatitis B from the vaccine.
The hepatitis B vaccine is recommended for:
All infants, beginning at birth
All children and adolescents who weren't vaccinated at birth
Anyone being treated for a sexually transmitted infection
Developmentally disabled people who live in an institutional setting
Health care workers, emergency workers and other people who come into contact with blood on the job
Anyone infected with HIV
People with chronic liver disease
People who live with someone who has hepatitis B
People with end-stage kidney disease
Sexual partner of someone who has hepatitis B
Travelers planning to go to an area of the world with a high hepatitis B infection rate
Other ways to reduce your risk of HBV include:
Know the HBV status of your marital partner. Abstain from sex until your married partner is cured of HBV or any other sexually transmitted infection.
Stop abusing drugs. Never share your needles and syringes with anyone.
Don't pierce or tattoo your body.
Don't commit fornication or adultery. Don't have unnatural non-procreative sex.
Ask about the hepatitis B vaccine before you travel. If you're planning an extended trip to a region where hepatitis B is more common, ask your doctor about the hepatitis B vaccine well in advance. It's usually given in a series of three injections over a six-month period.