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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.
The condition is caused by the hepatitis B virus. It's spread through contact with blood and body fluids from an infected person.
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 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.
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.
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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Hepatitis B is spread through contact with blood and body fluids from an infected person. For example, the virus can be spread:
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.
Certain things can increase your risk for being infected with hepatitis B. These include:
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:
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:
Many people who have a chronic infection have no symptoms.
Most people who have hepatitis B have an acute (short-term) infection.
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.
Call a doctor now if you have been diagnosed with hepatitis B and you have severe dehydration or these signs of liver failure:
Call to make an appointment if:
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.
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:
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.
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.
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.
Current as of:
February 9, 2022
Author: Healthwise StaffMedical Review: Kathleen Romito MD - Family MedicineE. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicineW. Thomas London MD - Hepatology
Current as of: February 9, 2022
Author: Healthwise Staff
Medical Review: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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