What is hepatitis B?
Hepatitis B is a virus that infects the liver. Most adults who get it have it for a short time and then get better. This is called acute hepatitis B.
Sometimes the virus causes a long-term infection, called chronic hepatitis B. Over time, it can damage your liver. Babies and young children infected with the virus are more likely to get chronic hepatitis B.
You can have hepatitis B and not know it. You may not have symptoms. If you do, they can make you feel like you have the flu. But as long as you have the virus, you can spread it to others.
What causes hepatitis B?
It's caused by the hepatitis B virus. It is spread through contact with the blood and body fluids of an infected person.
You may get hepatitis B if you:
- Have sex with an infected person without using a condom.
- Share needles (used for injecting drugs) with an infected person.
- Get a tattoo or piercing with tools that weren't sterilized.
- Share personal items like razors or toothbrushes with an infected person.
A mother who has the virus can pass it to her baby during delivery. Medical experts recommend that all pregnant women get tested for hepatitis B. If you have the virus, your baby can get shots to help prevent infection with the virus.
You cannot get hepatitis B from casual contact such as hugging, kissing, sneezing, coughing, or sharing food or drinks.
What are the symptoms?
Many people with hepatitis B don't know they have it, because they don't have symptoms. If you do have symptoms, you may just feel like you have the flu. Symptoms include:
- Feeling very tired.
- Mild fever.
- Not wanting to eat.
- Feeling sick to your stomach or vomiting.
- Belly pain.
- Tan-coloured bowel movements (stools).
- Dark urine.
- Yellowish eyes and skin (jaundice). Jaundice usually appears only after other symptoms have started to go away.
Most people with chronic hepatitis B have no symptoms.
How is hepatitis B diagnosed?
A simple blood test can tell your doctor if you have the hepatitis B virus now or if you had it in the past. Your doctor also may be able to tell if you have had the vaccine to prevent the virus.
If your doctor thinks you may have liver damage from hepatitis B, he or she may use a needle to take a tiny sample of your liver for testing. This is called a liver biopsy.
How is it treated?
In most cases, hepatitis B goes away on its own. You can relieve your symptoms at home by resting, eating healthy foods, drinking plenty of water, and avoiding alcohol and drugs. Also, find out from your doctor what medicines and herbal products to avoid, because some can make liver damage caused by hepatitis B worse.
Treatment for chronic hepatitis B depends on whether your infection is getting worse and whether you have liver damage. Most people with chronic hepatitis B can live active, full lives by taking good care of themselves and getting regular checkups. There are medicines for chronic hepatitis B, but they may not be right for everyone. Work with your doctor to decide if medicine is right for you.
Sometimes, chronic hepatitis B can lead to severe liver damage. If this happens, you may need a liver transplant.
Can hepatitis B be prevented?
The hepatitis B vaccine is the best way to prevent infection. The vaccine is a series of 3 or 4 shots. Check with your doctor or check your provincial immunization schedule to see if you or your child needs the hepatitis B vaccine.
A combination vaccine (Twinrix) that protects against both hepatitis B and hepatitis A also is available.
To avoid getting or spreading the virus to others:
- Use a condom when you have sex.
- Don't share needles.
- Wear disposable or plastic gloves if you have to touch blood.
- Don't share toothbrushes or razors.
- Don't get a tattoo, or make sure that the needles used have been cleaned properly and are sterile.
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Hepatitis B is a liver disease caused by infection with the hepatitis B virus.
How hepatitis B is spread
The virus is spread when blood, semen, or vaginal fluids (including menstrual blood) from an infected person enter another person's body. This usually happens through:
- Sexual contact. The hepatitis B virus can enter the body through a break in the lining of the rectum, vagina, urethra (the tube that carries urine out of the body), or mouth.
- Sharing needles and other equipment (such as cotton, spoons, and water) used for injecting illegal drugs.
- Work tasks. People who handle blood or instruments used to draw blood may become infected. Health care workers are at risk of infection if they are accidentally stuck with a used needle or other sharp instrument that has an infected person's blood on it. Infection also can occur if blood splashes onto an exposed surface, such as the eyes, the mouth, or a cut in the skin.
- Childbirth. A newborn baby can get the virus from his or her mother. This can happen during delivery when the baby comes in contact with the mother's body fluids in the birth canal. But breastfeeding doesn't spread the virus from a woman to her child.
- Body piercings and tattoos. The virus may be spread when needles used for body piercing or tattooing aren't sterilized and infected blood enters a person's skin.
- Toiletries. Grooming items such as razors and toothbrushes can spread the virus if they carry blood from a person who is infected.
In the past, blood transfusions were a common way of spreading hepatitis B. Organ transplants could also spread the disease. Today, all donated blood and organs in Canada and the United States are screened for the virus. So it is extremely unlikely that you could become infected from a blood transfusion or an organ transplant.
Contagious and incubation periods
Symptoms appear about 3 months after you have contact with the virus (incubation period). But they can appear as soon as 1 month to as late as 6 months after contact. Blood, semen, and vaginal fluids, whether fresh or dried, are highly contagious during this period and for several weeks after the start of symptoms.
If you have a short-term (acute) infection, in most cases you can't spread the virus after your body starts making a certain type of hepatitis B antibody. This generally takes several weeks. If you have a long-term (chronic) infection, you are able to spread the virus as long as you have an active infection.
Most people who have an acute hepatitis B infection don't have symptoms. But if you do have symptoms, they may include:
- Extreme tiredness (fatigue).
- Mild fever.
- Loss of appetite, nausea, and vomiting.
- Constant discomfort on the right side of the belly under the rib cage. (That's where the liver is located.)
- Tan-coloured bowel movements (stools).
- Dark urine.
- Jaundice. This means that the skin and whites of the eyes look yellow. Jaundice is a major sign of liver damage. It usually appears after other symptoms have started to go away.
Most people who have chronic infection have no symptoms.
You may get infected without knowing it. You may not find out that you have an infection until you have a routine blood test or donate blood. Finding out that a family member or someone you live with is infected also may cause you to be tested. Some people never know they have hepatitis B until a doctor finds that they have cirrhosis or liver cancer.
Most people who have hepatitis B have an acute (short-term) infection.
- They start to feel better after 2 to 3 weeks. They develop antibodies to hepatitis B. These antibodies provide lifelong protection against future infection.
- A small number of people have symptoms that last for months and sometimes years.
- The disease may be more severe in people over 60 years old.
If you stay infected with the virus for 6 months or longer, you have a chronic infection.
The risk of having chronic infection is related to the age at which you first become infected. The risk is highest for newborns infected at birth and children up to age 5.
Many people who have chronic hepatitis B won't develop complications. But about 15 to 25 out of 100 people who have chronic infection will die of cirrhosis or liver cancer.footnote 1 (This means that 75 to 85 people out of 100 who have a chronic infection won't die of these diseases.) Having a lot of virus in the body (a high viral load) increases the risk of getting cirrhosis and liver cancer.
- You are more likely to get cirrhosis if you carry a certain hepatitis B antigen, are older than 40, and have high liver enzymes. For more information, see the topic Cirrhosis.
- Risk factors for getting liver cancer after chronic infection include being male, having a family history of liver cancer, being over 40 years old, having cirrhosis, and also having hepatitis C.
Hepatitis D (delta) virus infection is a problem that can develop in relation to hepatitis B infection, but it's not common. It occurs only in those with hepatitis B. And it may make that infection more severe.
People who have hepatitis B who engage in high-risk behaviour (such as having multiple sex partners or injecting illegal drugs) are at increased risk for hepatitis C. They also are at higher risk of getting HIV, the virus that causes AIDS.
What Increases Your Risk
People who have certain behaviours or certain jobs are at high risk for becoming infected with hepatitis B.
Job risk factors include:
- Handling blood or body fluids as a routine part of your job. This includes health care workers, such as doctors, dentists, nurses, and blood and lab technicians, and students in these jobs. It also includes morticians and embalmers.
- Being an employee or resident of an institution for people who have developmental disabilities.
- Being an employee or inmate of a prison.
Lifestyle risk factors include:
- Being born in, or travelling to, parts of the world where hepatitis B is common or where a large number of people have been infected for a long time. Such areas include Southeast and Central Asia, the islands of the South Pacific, the Amazon River basin, the Middle East, Africa, Eastern Europe, and China.
- Being a man who has sex with men.
- Being sexually active. This includes having unprotected sex with someone who is infected with the virus or whose sexual history is unknown to you.
- Having more than one sex partner. (Your risk is higher if you have another sexually transmitted infection such as chlamydia.)
- Living with someone who has a chronic hepatitis B infection.
- Getting body piercings or tattoos from someone who doesn't sterilize his or her equipment.
- Sharing needles or other equipment (such as cotton, spoons, and water) to inject illegal drugs.
Other factors include:
- Being born to a woman who is infected with hepatitis B (if the newborn doesn't promptly receive the hepatitis B vaccine and hepatitis B immunoglobulin). But breastfeeding doesn't spread the virus to a child.
- Having a blood-clotting disorder, such as hemophilia, that requires you to receive clotting factors from human donors.
- Having severe kidney disease that requires you to have your blood filtered through a machine (hemodialysis).
- Having chronic liver disease.
- Being HIV-positive.
- Being bitten by a person who has the virus.
- Hepatitis B and C: Should I Be Tested?
When should you call your doctor?
If you see a person with hepatitis B become unconscious, call 911 or other emergency services.
Call a doctor right away if you have been diagnosed with hepatitis B and you have severe dehydration or these signs of liver failure:
- Extreme irritability.
- Trouble thinking clearly.
- Extreme sleepiness.
- Swelling of the arms, legs, hands, feet, belly, or face.
- Heavy bleeding from the nose, mouth, or rectum (including blood in the stool), or under the skin.
- Yellowing of the skin and the whites of the eyes.
Call to make an appointment if:
- You have risk factors for hepatitis B, such as handling blood or body fluids as a routine part of your job or having many sex partners.
- You have any symptoms of hepatitis B (see Symptoms).
- Someone in your household has been diagnosed with hepatitis B.
- Your sex partner has been diagnosed with hepatitis B.
- You have been bitten by or exposed to the blood or body fluids (such as semen or vaginal fluids, including menstrual blood) of someone who has hepatitis B.
Watchful waiting is a period of time during which you and your doctor observe your symptoms or condition without using medical treatment. Because of the need to prevent the spread of hepatitis B, watchful waiting isn't advised if you have symptoms of the virus or if you think you have come in contact with the virus.
Who to see
You may be referred to one of the following specialists who may work with your doctor to plan treatment:
Examinations and Tests
Your doctor will diagnose hepatitis B based on a physical examination and blood tests. He or she also will ask about your medical history (including possible risks for the virus, such as your job and sexual activity).
Blood tests to diagnose hepatitis B
Blood tests are done to help diagnose hepatitis B. They include:
- Hepatitis B antigens and antibodies. These help tell if you are or were infected with the virus. They also can show if you have been immunized and if you have long-term (chronic) infection. You also may get tested for the virus's genetic material ( HBV DNA). For more information, see Hepatitis B Virus Tests.
- Tests to see if the hepatitis A, hepatitis C, or Epstein-Barr viruses are causing your hepatitis.
- Tests to see if you are infected with hepatitis D along with hepatitis B.
- Hepatitis B and C: Should I Be Tested?
Blood tests to check for liver damage
Blood tests may be done to help find out if your liver has been damaged. They include:
- Bilirubin, albumin, and prothrombin time. These help show how well your liver is working. Cholesterol testing also may be done.
- Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, and lactic dehydrogenase (LDH). These show whether your liver is damaged or inflamed.
Tests if you are having treatment or are thinking about it
Tests may be done if you have chronic hepatitis and are considering antiviral treatment. These tests also may be used to find out whether treatment has helped control liver damage. The tests include:
- Imaging tests.
- Removing a tissue sample from the liver (liver biopsy).
Test for liver cancer
An alpha-fetoprotein (AFP) test may be done. If the AFP level is high, it may point to liver cancer.
If you have chronic infection, you will need to visit your doctor regularly. He or she will do blood tests to check your liver function and the activity of the virus in your body.
Some of the tests can tell your doctor if the virus is multiplying in your liver. This raises your risk for chronic hepatitis.
The Canadian National Advisory Committee on Immunization (NACI) recommends that all pregnant women have the hepatitis B surface antigen test. The test can show if a woman has a current hepatitis B infection. This test also may be repeated later in the pregnancy if a woman is at high risk for infection.
It is also recommended that you get tested if you:
- Have travelled to or lived in a country where hepatitis B is common.
- May be exposed to blood at work.
- Have unsafe sex.
- Share needles or other drug equipment.
You can be tested for hepatitis B before getting vaccinated.
- Testing will show if you have an active hepatitis B infection and need treatment.
- If testing shows that you are already protected against hepatitis B, you won't need to get the hepatitis B vaccine.
- It's not harmful to get the vaccine even if you already have antibodies against the virus in your blood.
Treatment of hepatitis B infection depends on how active the virus is and whether you are at risk for liver damage such as cirrhosis.
Treatment of short-term (acute) hepatitis B
Treatment depends on whether you:
- Have been recently infected with the virus.
- Have the symptoms of an acute infection.
- Have chronic infection.
If you have not gotten a hepatitis B vaccine and think you may have been exposed to the virus, you should get a shot of hepatitis B immunoglobulin (HBIG) and the first of three shots of the hepatitis B vaccine. It is important to receive this treatment within 7 days after a needle stick and within 2 weeks after sexual contact that may have exposed you to the virus. The sooner you receive treatment after exposure, the better the treatment works.
If you have the symptoms of acute infection, treatment with antiviral medicine usually isn't needed. Home treatment—such as eating well, drinking plenty of fluids, and avoiding alcohol and drugs— usually will relieve your symptoms.
In some cases, you may be given medicine to treat an acute infection. But using medicine usually isn't done unless a person is very sick.
Treatment of long-term (chronic) hepatitis B
Treatment depends on how active the virus is in your body and your chance of liver damage. The goal of treatment is to stop liver damage by keeping the virus from multiplying.
Antiviral medicine is used if the virus is active and you are at risk for liver damage. Medicine slows the ability of the virus to multiply.
Antiviral treatment isn't given to everyone who has chronic hepatitis B.
Whether or not you take medicine, you will need to visit your doctor regularly. He or she will do blood tests to check your liver and the activity of the hepatitis B virus in your body.
Some of the tests can find out whether the virus is multiplying in your liver, which would increase your risk of liver damage.
If you develop advanced liver damage and your condition becomes life-threatening, you may need a liver transplant. But not everyone is a good candidate for a liver transplant.
You can protect yourself against hepatitis B infection by avoiding contact with the body fluids of someone whose health and sexual history aren't known to you. To prevent infection:
- Use a condom when you have sex.
- Do not share needles.
- Do not share toothbrushes or razors.
- Wear disposable or plastic gloves if you have to touch blood.
- Don't get a tattoo unless you are sure the needles have been cleaned properly and are sterile.
Hepatitis B vaccine
The hepatitis B vaccine is the most effective way to prevent infection. The vaccine is up to 95% effective against hepatitis B if you receive all the shots in the vaccination series (3 or 4 shots given at different times).footnote 2
The vaccine provides protection against infection for at least 20 years.footnote 3 A combination vaccine for hepatitis A and B also is available.
Immunization schedules vary from province to province. Vaccination is generally recommended for:
- All newborn babies. Vaccination is especially recommended for babies born to mothers infected with hepatitis B virus.
- Anyone age 18 years or younger who has not previously received the vaccine.
- People who inject illegal drugs.
- People who have had more than one sex partner in the past 6 months or who have a history of sexually transmitted infections.
- Men who have sex with men.
- Household contacts and sex partners of people who have hepatitis B.
- People who have blood-clotting disorders, such as hemophilia, and have received clotting factors from human donors.
- People who have a severe kidney disease that requires them to have their blood filtered through a machine (hemodialysis).
- People who have liver disease or are infected with HIV.
- Health care workers and public safety workers who are likely to be exposed to blood.
- Staff and residents of prisons or institutions for the developmentally disabled.
- People who will spend more than 6 months in parts of the world where hepatitis B is common or where a large number of people have chronic HBV infection. To find the countries where hepatitis B is common, go to wwwnc.cdc.gov/travel/yellowbook/2010/chapter-2/hepatitis-b.aspx.
Discuss vaccination with your doctor even if you aren't in one of the recommended groups. In the United States, about 15 out of 100 of those who become infected don't know how they got infected.footnote 4
In some cases, a doctor will order post-vaccination testing to make sure you have developed immunity to the virus. People who need this testing include those who have an impaired immune system or those who are health care workers or sex partners of people who have chronic infection.
If you are exposed to the virus before you have received all of the shots in the vaccination series, you may be given a dose of hepatitis B immunoglobulin (HBIG) soon afterward. In most cases, this will prevent infection until the vaccine takes effect.
If you have had sex with someone who has hepatitis B and you haven't received all doses of the hepatitis B vaccine, you should receive a shot of HBIG—in addition to continuing the vaccine series—within 14 days of being exposed to the virus.
Avoiding spreading the virus if you have it
If you are already infected, you can take steps to prevent spreading the virus to others. This includes not donating blood and not sharing razors or other toiletries.
Home treatment can help relieve symptoms and prevent the spread of hepatitis B virus (HBV).
- Reduce your activity to match your energy. You don't have to stay in bed, but listen to your body. Slow down when you are tired.
- If you are feeling tired at work or school, try to reduce your workload.
- Avoid strenuous exercise.
- As you start to feel better, slowly go back to your regular activities. If you try to go back to your regular pace too soon, you may get sick again.
- Even though food may not appeal to you, it is important to eat well. For most people, nausea and loss of appetite become worse as the day goes on. Try eating a substantial (but not heavy) meal in the morning and lighter meals later in the day.
- Doctors used to recommend a high-calorie, protein-rich diet to people who have hepatitis. This is no longer believed to help. And such foods can be hard to eat when you feel nauseated. Try to have a balanced diet while eating foods that appeal to you.
It is important to keep your body well-hydrated when you have hepatitis B, especially if you have been vomiting.
- Drink plenty of water.
- If you can tolerate them, fruit juices and broth are other good choices, because they provide extra calories.
- Many sports drinks, such as Gatorade or Powerade, can help replace essential minerals (electrolytes) that are lost during vomiting. You can also make your own rehydration drink.
Avoid alcohol and drugs
Hepatitis makes it hard for your liver to process drugs and alcohol. If you take drugs (prescription or illegal) or drink alcohol when you have hepatitis, their effects may be more powerful and may last longer. They also can make liver damage worse.
- If you are taking prescription medicines, your doctor may tell you to stop using them until your liver has had time to heal. Don't stop taking the medicines unless your doctor has told you to do so.
- Check with your doctor before taking any over-the-counter medicines, including herbal products and acetaminophen (such as Tylenol). Acetaminophen can make liver disease worse, especially if you continue to drink alcohol.
- Avoid alcohol until your doctor feels that your liver is completely healed. This may take as long as 3 to 4 months.
Try to control itching
People who have hepatitis sometimes have itchy skin. You can control itching by keeping cool and out of the sun, wearing cotton clothing, or using over-the-counter antihistamines such as a non-drowsy one like loratadine (Claritin) or one that may make you sleepy like diphenhydramine (Benadryl). Talk to your doctor before taking these medicines.
Treatment with medicine usually isn't recommended for people who have acute hepatitis B. Antiviral medicine may be used for chronic infection if the virus is multiplying. You also may take medicine if you have liver damage, such as cirrhosis, or could develop it.
Antiviral therapy may not help if you already have severe liver damage.
The Canadian Association for the Study of the Liver has made recommendations on who should receive antiviral treatment for chronic hepatitis B.
It's important to weigh the benefits of treatment against the risks. Treatment for chronic hepatitis B doesn't cure the disease, but it does suppress it.
- Interferons, such as interferon alfa-2b and pegylated interferon alfa-2a
- Nucleoside reverse transcriptase inhibitors (NRTIs) such as adefovir, entecavir, lamivudine, telbivudine, and tenofovir
What to think about
- Interferons have common side effects, including fever, headaches, and hair loss. They may also cause mental problems or make them worse.
- If you have cirrhosis, you cannot use interferons. But you can use adefovir, entecavir, lamivudine, telbivudine, and tenofovir.
- After any kind of treatment for hepatitis B, the virus may become active again (relapse).
There is no surgical treatment for hepatitis B.
If you have advanced liver damage because of hepatitis and your condition becomes life-threatening, you may need a liver transplant.
In rare cases, acute hepatitis B progresses rapidly to liver failure, a deadly condition called fulminant hepatitis. For people who develop this condition, a liver transplant is the only treatment choice.
- American Public Health Association (2015). Hepatitis B. In DL Heymann, ed., Control of Communicable Diseases, 20th ed., pp. 257–264. Washington, DC: American Public Health Association.
- American Academy of Pediatrics (2015). Hepatitis B. In DW Kimberlin et al., eds., Red Book: 2015 Report of the Committee on Infectious Diseases, 30th ed., pp. 400–423. Elk Grove Village, IL: American Academy of Pediatrics.
- World Health Organization (2015). Hepatitis B fact sheet. Available online: http://www.who.int/mediacentre/factsheets/fs204/en/index.html. Accessed May 7, 2015.
- Perrillo R (2010). Hepatitis B and D. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed., vol. 2, pp. 1287–1312. Philadelphia: Saunders Elsevier.
Other Works Consulted
- Centers for Disease Control and Prevention (CDC) (2012). Updated CDC recommendations for the management of hepatitis B virus–infected health-care providers and students. MMWR, 61(RR03): 1–12.
- Janssen, H (2005). Pegylated interferon alfa-2b alone or in combination with lamivudine for HBeAg-positive chronic hepatitis B: A randomised trial. Lancet, 365(9454): 123–129.
- Lok SFL, McMahon BJ (2009). Chronic Hepatitis B: Update 2009. Available online: http://www.aasld.org/practiceguidelines/Documents/Bookmarked%20Practice%20Guidelines/Chronic_Hep_B_Update_2009%208_24_2009.pdf.
- Papatheodoridis GV, et al. (2008). Current treatment indications and strategies in chronic hepatitis B virus infection. World Journal of Gastroenterology, 14(45): 6902–6910.
- Sorrell MF, et al. (2009). National Institutes of Health consensus development conference statement: Management of hepatitis B. Annals of Internal Medicine, 150(2): 104–110.
- U.S. Preventive Services Task Force (2009). Screening for hepatitis B virus infection in pregnancy: U.S. Preventive Services Task Force reaffirmation recommendation statement. Annals of Internal Medicine, 150(12): 869–874.
- Weinbaum CM, et al. (2008). Recommendations for identification and public health management of persons with chronic hepatitis B virus infection. MMWR, 57(RR-08): 1–20. Also available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5708a1.htm.
Current as of: September 23, 2020
Author: Healthwise Staff
Kathleen Romito MD - Family Medicine
Donald Sproule MDCM, CCFP - Family Medicine
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Elizabeth T. Russo MD - Internal Medicine
W. Thomas London MD - Hepatology
Current as of: September 23, 2020