The viral infection hepatitis B is transmitted through bodily fluids such as blood. There’s no cure for this common liver disease, but an effective vaccine and antiviral medications are available.

Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). HBV is one of five types of viral hepatitis. The others are hepatitis A, C, D, and E. Each is a different type of virus. Types B and C are most likely to become chronic, or long lasting.

According to the World Health Organization, around 296 million people around the world are living with hepatitis B. Around 1.5 million people newly contracted chronic hepatitis B in 2019.

HBV infection can be acute or chronic.

Acute hepatitis B causes symptoms to appear quickly in adults. Infants who contract it at birth rarely develop only acute hepatitis B. Nearly all hepatitis B infections in infants go on to become chronic.

Chronic hepatitis B develops slowly. Symptoms may not be noticeable unless complications develop.

Symptoms of acute hepatitis B may not be apparent for months. But common symptoms include:

  • fatigue
  • dark urine
  • joint and muscle pain
  • loss of appetite
  • fever
  • abdominal discomfort
  • weakness
  • yellowing of the whites of the eyes and skin (jaundice)

Any symptoms of hepatitis B need urgent evaluation. Symptoms of acute hepatitis B are worse in people over age 60.

Let your doctor know immediately if you’ve been exposed to hepatitis B. You may be able to prevent infection.

Hepatitis B is a viral infection that’s transmitted through blood or other bodily fluids, including semen or vaginal fluids.

Some of the ways hepatitis B can be transmitted include:

  • having sex with a person who has HBV without using a condom or other barrier methods
  • sharing toothbrushes, razors, or nail clippers that have been exposed to blood
  • receiving a tattoo or body piercing with equipment that has not been sterilized
  • injecting drugs and sharing needles, syringes, or other equipment
  • from a birthing parent to a newborn baby

Although the virus may be found in the saliva, hepatitis B is not transmitted through:

  • kissing
  • sneezing
  • coughing
  • sharing utensils

Certain groups have a particularly high risk of HBV infection. These include:

  • healthcare workers
  • people who use injection drugs
  • infants born to birthing parents who have HBV
  • sexual partners of people with HBV
  • people receiving dialysis for kidney disease

According to the WHO, around 296 million people around the globe live with chronic HBV. Around 1.5 million new infections occur every year.

According to the Centers for Disease Control and Prevention (CDC), chronic hepatitis B affects approximately 1.2 million people in the United States.

But HBV often goes undetected. In fact, the WHO estimates that only about 10.5% of people living with hepatitis B were aware of their condition as of 2019.

Doctors can usually diagnose hepatitis B with blood tests. Screening for hepatitis B may be recommended for people who:

  • use injection drugs
  • receive kidney dialysis
  • were born in a country where hepatitis B is common
  • are a household contact or sexual partner of someone with hepatitis B
  • are taking medications that suppress the immune system
  • are donating blood or organs
  • are an infant born to a birthing parent with hepatitis B
  • have lab test results that show elevated liver enzymes
  • are pregnant
  • are men who have sex with men
  • have HIV

To screen for hepatitis B, your doctor will perform a series of blood tests.

Hepatitis B surface antigen test

A hepatitis B surface antigen test shows if you have an active infection. A positive result means you have hepatitis B and can transmit the virus to others. A negative result means you don’t currently have hepatitis B.

This test doesn’t distinguish between chronic and acute infection. This test is used together with other hepatitis B tests to determine the state of a hepatitis B infection.

Hepatitis B core antibody test

The hepatitis B core antigen test shows whether you’re currently living with HBV. Positive results usually mean you have acute or chronic hepatitis B. It may also mean you’re recovering from acute hepatitis B.

Hepatitis B surface antibody test

A hepatitis B surface antibody test is used to check for immunity to HBV. A positive test means you’re immune to hepatitis B.

There are two possible reasons for a positive test:

  • you may have been vaccinated
  • you may have recovered from an acute HBV infection and can no longer transmit the virus

Liver function tests

Liver function tests are important in people with hepatitis B or any liver disease.

These tests check your blood for the number of enzymes your liver makes. High levels of liver enzymes indicate a damaged or inflamed liver. These results can also help determine which part of your liver may be functioning abnormally.

If liver function tests show high levels of liver enzymes, you might need testing for hepatitis B, C, or other liver infections. Hepatitis B and C viruses are a major cause of liver damage throughout the world.

You’ll likely also need an ultrasound of the liver or other imaging tests.

If you think you may have been exposed to hepatitis B, it’s important to talk with a healthcare professional as soon as possible.

A doctor or other healthcare professional may administer the first dose of the hepatitis B vaccine and a shot of hepatitis B immunoglobulin. This is a combination of antibodies that provide short-term protection against the virus.

Though both can be given up to a week after exposure, they’re most effective at preventing infection if administered within 48 hours.

If you receive a diagnosis of acute hepatitis B, a doctor may refer you to a specialist. They may advise you to get regular blood tests to ensure you don’t develop chronic hepatitis.

Many people with acute hepatitis B don’t experience serious symptoms. But if you do, it can help to:

  • get plenty of rest
  • wear loose clothing
  • maintain a cool environment
  • take over-the-counter pain mediation, like naproxen, when needed

Other lifestyle changes may also be needed to manage your infection, such as:

  • eating a nutritious, balanced diet
  • avoiding substances that can harm your liver, such as:
    • alcohol
    • certain herbal supplements or medications, including acetaminophen (Tylenol)

If blood tests show you still have an active infection after 6 months, your doctor may recommend further treatment, including medications to help control the virus and prevent liver damage.

Medications

Some medications a doctor may prescribe to treat chronic hepatitis B include:

  • Peginterferon alfa-2a (Pegasys): This medication is a type of interferon. It’s used to stimulate immune function so your body can fight HBV more effectively. It’s usually administered through a weekly injection for 6 months to 1 year.
  • Entecavir (Baraclude): Most often available in tablet form, this antiviral medication is one of the most commonly prescribed treatments used to treat chronic HBV.
  • Tenofovir (Viread, Vemlidy): An antiviral medication, tenofovir is taken as a tablet once daily. It’s used to reduce symptoms of viral infections like chronic HBV or HIV.
  • Adefovir dipivoxil (Hepsera): This medication is taken orally. It belongs to a class of medications known as nucleotide analogs. It works to reduce the amount of HBV in your body to treat chronic infections.
  • Telbivudine (Tyzeka or Sebivo): This pill is taken once a day. It’s usually only considered after other treatment options have been ruled out.
  • Lamivudine (Epivir-HBV): Also commonly known as 3TC, lamivudine is an antiretroviral medication available in liquid or tablet form. It’s usually not used in the United States because more effective treatments exist, and people may develop drug resistance within a couple of years.
  • Interferon alfa-2b (Intron A): This medication is administered through an injection. It can increase immune function to help the body fight chronic hepatitis B. It’s an older drug that’s not used often in the United States.

Complications of having chronic hepatitis B include:

  • hepatitis D infection
  • liver scarring (cirrhosis)
  • liver failure
  • liver cancer
  • death

Hepatitis D infection can only occur in people with hepatitis B. Hepatitis D is uncommon in the United States but can also lead to chronic liver disease.

Hepatitis B can be transmitted from a birthing parent to a newborn infant. This is because the newborn is exposed to blood and bodily fluids during delivery.

In fact, 90% of mothers with an acute hepatitis B infection and 10% to 20% of mothers with chronic hepatitis B will transmit the virus to their newborn, estimates the American College of Obstetricians and Gynecologists.

For this reason, birthing parents are routinely screened for hepatitis B during each pregnancy.

Additionally, the hepatitis B vaccine and hepatitis B immune globulin are both administered to infants with an HBV-positive birthing parent within 12 hours of birth to prevent infection.

According to the CDC, without this treatment, around 40% of infants with an HBV-positive birthing parent would develop chronic hepatitis B, of which approximately 25% would eventually die from chronic liver disease.

The best way to prevent hepatitis B infection is to get the hepatitis B vaccine. It’s very safe and effective.

The CDC now recommends nearly universal vaccination for hepatitis B. This includes:

  • all infants, within 24 hours of birth
  • children and adolescents who weren’t vaccinated at birth
  • unvaccinated adults ages 19 through 59
  • unvaccinated adults ages 60 and older with risk factors for hepatitis B

Adults ages 60 and older who do not have known risk factors for hepatitis B may still choose to get vaccinated.

The following groups are at greater risk of hepatitis B:

  • people living in institutional settings
  • people whose work brings them into contact with blood
  • people living with HIV
  • people with hepatitis C infection
  • men who have sex with men
  • people with multiple sexual partners
  • people who are seeking treatment for a sexually transmitted infections (STIs)
  • people with current or recent injection drug use
  • family members or sexual partners of those with hepatitis B
  • people with chronic liver disease
  • people traveling to areas with high rates of hepatitis B
  • people on maintenance dialysis
  • people who are incarcerated

The hepatitis B vaccine is usually administered in three shots, given 1 month and 6 months after the first dose. Another recently approved vaccine is completed in two doses spaced 1 month apart.

Hepatitis B is highly contagious. It’s transmitted through contact with blood and certain other bodily fluids. Although the virus can be found in saliva, it’s not transmitted through sharing utensils or kissing. It’s also not transmitted through sneezing, coughing, or breastfeeding.

Symptoms of hepatitis B may not appear for 3 months after exposure. Symptoms can last for several weeks.

But even without symptoms, you can still transmit the infection to others. The virus can live outside the body and remains infectious for at least 7 days.

Possible methods of transmission include:

  • direct contact with blood
  • from birthing parent to baby during birth
  • being pricked with a contaminated needle
  • intimate contact with a person with HBV
  • oral, vaginal, and anal sex without a barrier method
  • using a razor or any other personal item with remnants of bodily fluid

Hepatitis B is a highly contagious condition. It’s associated with many serious complications, some of which can be life threatening.

But there are many treatment options available and multiple ways you can prevent infection, including getting vaccinated.

If you suspect you may have been exposed to hepatitis B, it’s important to talk with a doctor to prevent infection and determine the best course of treatment for you.

Is hepatitis B curable?

There’s currently no known cure for hepatitis B, but there are many ways you can prevent infection and avoid transmitting the virus to others.

The most effective and safe way to prevent hepatitis B is to get vaccinated. You can also use barrier methods, like condoms, when having sex and avoid sharing needles.

How long can you live with hepatitis B?

Most people who contract hepatitis B during adulthood fully recover within 1 to 3 months.

People with chronic hepatitis B may have a higher risk of developing long-term liver problems, like cirrhosis or liver cancer, which require treatment and may be life threatening.

Keep in mind that the risk of developing chronic hepatitis B is higher for babies and children, especially if they have not been vaccinated against the virus.

Can you get hepatitis B from blood transfusions?

Though hepatitis B is transmitted through bodily fluids, including blood, the risk of transmission from a blood transfusion is extremely low.

This is because all blood used for blood transfusions in the United States has been screened for hepatitis B since 1972, making transfusion-transmitted HBV very rare.

Who should get the hepatitis B vaccine?

Infants should receive their first dose of the hepatitis B vaccine within 24 hours of birth and subsequent doses between 6 and 18 months of age.

Children, adolescents, and adults who have not received the vaccine should also be vaccinated against hepatitis B.

This is especially important for those at an increased risk of infection, such as:

  • people living in institutionalized settings
  • people with multiple sexual partners
  • people who use injection drugs
  • men who have sex with men
  • people who regularly have contact with blood or bodily fluids
  • people with certain chronic conditions