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What is hepatitis B?
Hepatitis B is a virus that infects the liver. Most people 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. As long as you have the virus, you can spread it to others.
What causes it?
The condition is caused by the hepatitis B virus. It's spread through contact with blood and body fluids from an infected person.
What are the symptoms?
Most people who get hepatitis B do not have symptoms. If you have symptoms, you may just feel like you have the flu. Symptoms usually start to go away in 2 to 3 weeks and may include:
- A fever.
- Light-colored stools.
- Dark urine.
- Yellow skin and eyes (jaundice).
How is it diagnosed?
A 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 do tests to check for liver damage.
How is hepatitis B treated?
Treatment depends on how active the virus is and if you are at risk for liver damage, such as cirrhosis. For short-term (acute) hepatitis B, you may get a shot of hepatitis B immunoglobulin (HBIG) and the hepatitis B vaccine. For long-term (chronic) hepatitis B, you may get antiviral medicine.
Can it be prevented?
The hepatitis B vaccine is the best way to prevent infection. At-risk adults and all babies, children, and teenagers should be vaccinated. You can do things to help avoid an infection. Use condoms during sex. Wear protective gloves if you have to touch blood. And don't share toothbrushes or razors.
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How it Spreads
Hepatitis B is spread through contact with blood and body fluids from an infected person. For example, the virus can be spread:
- Through infected blood, semen, and other body fluids during sexual contact.
- When people share needles to inject drugs.
- When an infected person shares items that may have blood on them. Examples are a razor or toothbrush.
- When needles used for tattoos, body piercing, or acupuncture are not cleaned properly.
People who handle blood may become infected with the virus. For example, health care workers may get the virus when they treat an infected person.
A mother who has the virus can pass it to her baby during the birth. If you are pregnant and think you may have been exposed to hepatitis B, get tested. If you have the virus, your baby can be given shots to help prevent getting the virus.
You can't get hepatitis B from casual contact such as hugging, kissing, sneezing, coughing, or sharing food or drinks.
What Increases Your Risk
Certain things can increase your risk for being infected with hepatitis B. These include:
- Handling blood or body fluids.
- Living in parts of the world where hepatitis B is common.
- Being a man who has sex with men.
- Living with someone who has a chronic hepatitis B infection.
- Getting body piercings or tattoos using needles that weren't cleaned the right way.
- Sharing needles or other things (such as cotton, spoons, and water) to inject drugs.
- Being born to a woman who has hepatitis B. 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. (This is called hemodialysis.)
The hepatitis B vaccine is the best way to prevent infection. The vaccine is a series of 2, 3, or 4 shots. At-risk adults and all babies, children, and teenagers should be vaccinated.
A combination vaccine 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 gloves if you have to touch blood.
- Don't share toothbrushes or razors.
- Don't get a tattoo. Or, if you do, make sure that the needles used have been cleaned properly and are sterile.
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.
Many 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-colored 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.
Many people who have a chronic infection have no symptoms.
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 give them lifelong protection against getting infected again.
- A small number of people have symptoms that last for months and sometimes years.
- The disease may be more severe in people who are older than 60.
If you stay infected with the virus for 6 months or longer, you have a chronic infection.
The risk of having a chronic infection is related to your age when you first become infected. The risk is highest for newborns infected at birth and children up to age 5.
A chronic hepatitis B infection can lead to cirrhosis. This can increase the risk of liver cancer.
When to Call a Doctor
Call a doctor now 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, such as a headache, feeling tired, or an upset stomach.
- 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.
In most areas, public health clinics or health departments are able to diagnose and provide low-cost assessment and treatment of hepatitis B.
Watchful waiting is a wait-and-see approach. 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.
Exams and Tests
Your doctor will diagnose hepatitis B based on a physical exam and blood tests. You will also be asked about your past health. This includes possible risks for the virus, such as your job and sexual activity.
Blood tests include:
- Hepatitis B antigens and antibodies. These tests help tell if you are or were infected with the virus. They also can show if you've been immunized and if you have long-term (chronic) infection. You also may get tested for the virus's genetic material (HBV DNA).
- Tests to see if the hepatitis A, hepatitis C, or Epstein-Barr viruses are causing your hepatitis.
- Tests to see if you also are infected with hepatitis D.
Blood tests may also be done to help find out if your liver has been damaged.
Treatment of a hepatitis B infection depends on how active the virus is. It also depends on whether you are at risk for liver damage such as cirrhosis.
Treatment of short-term (acute) hepatitis B
If you haven't had a hepatitis B vaccine and think you may have been exposed to the virus, you should get a shot of hepatitis B immunoglobulin (HBIG). You should also get the first of three shots of the hepatitis B vaccine. Make sure to get this treatment within 7 days after a needle stick and within 2 weeks after sexual contact that may have exposed you to the virus.
In some cases, you may get medicine to treat an acute infection. But this usually isn't done unless you are very sick.
Treatment of long-term (chronic) hepatitis B
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.
- Reduce your activity to match your energy level.
- Avoid alcohol for as long as your doctor tells you to. This may be months. Alcohol can make liver problems worse.
- Make sure your doctor knows all the medicines you take. Some medicines, such as acetaminophen (Tylenol), can make liver problems worse. Do not take any new medicines unless your doctor says it is okay.
- Be safe with medicines. If your doctor prescribes antiviral medicine, take it exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.
- If you have nausea or vomiting, try to eat smaller meals and eat more often.
- Drink plenty of fluids. If you have kidney, heart, or liver disease and have to limit fluids, talk with your doctor before you increase the amount of fluids you drink.
- If you have itchy skin, keep cool, stay out of the sun, and wear cotton clothing. Talk to your doctor about medicines that can be used for itching. Read and follow the instructions on the label.
How to avoid spreading hepatitis B
- Tell the people you live with or have sex with about your illness as soon as possible. The CDC recommends that people in close contact with an infected person get the hepatitis B vaccine.
- Do not donate blood or blood products, organs, sperm, or eggs (ova).
- Stop all sexual activity or use latex condoms. Do this until your doctor tells you that you can no longer give hepatitis B to others. Avoid anal contact with a sex partner while you are infected.
- Do not share personal items that may have your blood on them. These include razors, toothbrushes, towels, and nail files.
- Use lotions or ointments to prevent chapped or broken skin. These skin problems can expose others to your blood.
- Tell your doctor, dentist, and anyone else who may come in contact with your blood about your illness.
- If you are pregnant, tell the doctor who will deliver your baby about your illness. Be sure your baby gets medicine to prevent infection. This should start right after birth.
- If you get blood on your clothing or other fabrics, clean them well.
- Be sure to carefully get rid of sanitary napkins and tampons or other disposable items that have your blood on them. Place them in sealed plastic bags before you throw them away.
- Use a solution of 1 part bleach to 10 parts water to clean surfaces that have your blood or any other body fluid (such as semen or menstrual blood) on them. These surfaces include toilet seats, countertops, and floors.
- If you have long-term hepatitis B, always use latex condoms during any sexual activity. You can infect others with the virus even if you do not have symptoms.
Current as of: February 9, 2022
Author: Healthwise Staff
Kathleen Romito MD - Family Medicine
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
W. Thomas London MD - Hepatology
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