What is hepatitis B?
Hepatitis B is a viral infection that affects your liver. It causes inflammation in your liver tissues, which is what “hepatitis” means. It begins as an acute infection that’s usually short-lived. But in some people, it turns into a chronic infection that never goes away.
Long-term inflammation does serious damage to your liver over time. It can lead to cirrhosis and liver failure. Like other chronic liver diseases, hepatitis B infection can do this damage without causing symptoms. Many people don’t realize they’re infected.
Why is it called “hepatitis B”?
There are several different viruses that can infect your liver and cause inflammation (hepatitis). They include hepatitis A, B, C, D and E. Each is a little different in how they’re transmitted, how they affect your body and how they’re treated (or prevented).
What distinguishes hepatitis B from other hepatitis viruses?
Some distinguishing features of hepatitis B include:
- Hepatitis B has a safe and effective vaccine that makes it preventable. The World Health Organization (WHO) recommends vaccination for all children as soon as possible after birth.
- Hepatitis B disproportionately affects children. Only 5% of adults who are infected go on to develop a chronic infection, but 30% of children under the age of 6 do.
- As hepatitis B spreads through bodily fluids, birthing parents can infect their babies at birth. Up to 90% of infants infected with hepatitis B develop a chronic infection.
- Chronic hepatitis B is treatable, but not curable. Antiviral medications can help control the infection, but you’ll have to take special care of your liver for the rest of your life.
How common is hepatitis B infection?
Hepatitis B is the most common liver infection in the world. As many as 2 billion people (or 1 in 3) have been infected worldwide. Approximately 250 million people worldwide are living with chronic hepatitis B infection, many unaware.
It’s less common in the U.S. than in some other places, thanks to the vaccine. The Centers for Disease Control and Prevention (CDC) estimates approximately 20,000 new acute infections occur in the U.S. each year. An estimated 862,000 people in the U.S. are living with chronic hepatitis B.
Symptoms and Causes
What are the symptoms of hepatitis B infection?
Not everyone has symptoms. If you do, they can range from mild to severe. You may have symptoms (or not) during the acute phase of infection, and you may also have them (or not) with chronic infection. You’re still contagious with or without symptoms.
Typical symptoms of infection include:
- Loss of appetite.
- Nausea and vomiting.
- Abdominal pain.
- Weakness and fatigue.
- Joint pain.
You may also have symptoms of liver disease, including:
- Jaundice (yellowing of your skin and the whites of your eyes).
- Dark-colored urine.
- Light or clay-colored poop.
- Swelling with fluid in your belly or arms and legs.
With acute infection, symptoms of liver disease may indicate a more severe reaction than usual. Although many people clear the HBV virus without treatment, you should see a healthcare provider if you have symptoms of liver disease.
With chronic infection, you may have mild or vague symptoms on an ongoing basis, or you may not have symptoms at all for decades. When symptoms appear later, especially symptoms of liver disease, it may indicate your liver is beginning to fail.
How do you get hepatitis B?
Hepatitis B infection comes from the hepatitis B virus (HBV). The virus spreads through bodily fluids. Transmission occurs when fluids from the body of a person who’s infected enter the body of a person who’s uninfected. This might happen through:
- Sexual contact.
- Contact with an open wound.
- Sharing needles or syringes.
- Sharing a toothbrush or razor.
- Accidental stick from an infected sharp instrument.
HBV can live on surfaces outside of your body for at least seven days. So, used instruments that haven’t been sterilized can still carry the virus. This includes medical instruments and common items like a toothbrush or razor that may have provoked bleeding.
Besides blood, HBV also lives in other bodily fluids, including saliva. But unlike some viruses, hepatitis B isn’t easily transmitted through saliva. That means you aren’t likely to get it from sharing food or eating utensils or from someone coughing or sneezing on you.
Who is more likely to get hepatitis B?
You’re more likely to get hepatitis B if you belong to a community where infection is more common. The more people around you may be infected, the more chances the virus has to infect you. Communities with higher rates of infection include:
- People with HIV. As much as 7.5% of people with HIV also have chronic hepatitis B.
- People who use intravenous drugs. Rates of hepatitis B infection have risen steeply in states recently affected by the opioid crisis.
- People of African, Asian or Pacific Island descent. Infection rates in these countries range between 2% and 8%. In the U.S., these peoples make up more than half of those with chronic hepatitis B infection.
How do you get chronic hepatitis B?
Chronic hepatitis B develops when your immune system fails to fight off the virus. Most people successfully fight it off during the acute phase of the infection. The acute phase is when your immune system recognizes the virus and launches its attack.
When you have symptoms of illness after an infection, such as fever, nausea and vomiting, those symptoms are part of your immune response. Your immune system is trying to get rid of the virus by purging and burning it out. That’s the acute phase.
Sometimes, some people’s immune systems don’t succeed in clearing the HBV virus during the acute phase. For various reasons, their immune response is weaker than necessary. The acute phase only happens once. If the virus survives, there isn’t another one.
A person might have a weaker immune response to the virus if they:
- Are a young child whose immune system is still developing.
- Have another infection at the same time.
- Have a chronic medical condition that compromises their immune system.
- Receive immunosuppressant therapy or chemotherapy.
What is reactivated hepatitis B?
Sometimes after overcoming an acute hepatitis B infection, something causes your immune system to weaken against the virus later in life. Maybe your immune system was strong at the time of infection, but now you have a condition that weakens it.
When this happens, the once-defeated virus can become active in your body again. Reactivated hepatitis B can be temporary or lasting. But because it tends to occur in immune-suppressed people, it may be especially severe and even cause acute liver failure.
How long are you contagious with hepatitis B?
You’re contagious as long as the virus is active in your body. If you have an acute infection, it may last from a few weeks to six months, and you’re contagious that whole time. If you have a chronic infection, you’re contagious as long as it lasts, which is usually for life.
What are the possible complications of hepatitis B infection?
Most complications come from chronic infection, but some people may have complications with acute infection. Though it’s not common, some people experience acute liver failure with acute hepatitis B infection, which is a life-threatening emergency.
Complications of chronic hepatitis B can include:
- Hepatitis D. Hepatitis D, or delta virus, is another viral hepatitis infection that only affects people with hepatitis B. If you have chronic hepatitis B, you can get both viruses. This is called superinfection. It doubles the stress on your liver and can lead to acute liver failure.
- Cirrhosis. Chronic liver inflammation leads to cirrhosis in some people. It takes a long time and depends on many factors, such as the overall health of your liver and other conditions that might affect it. Cirrhosis happens when injured liver tissues are gradually replaced with scar tissue. The scar tissue stops your liver from functioning, which leads to chronic liver failure.
- Chronic liver failure. Chronic liver failure is a gradual process where your liver loses its ability to function over time. It usually follows cirrhosis. Even though it happens slowly, chronic liver failure is life-threatening. You can’t live without a functioning liver. Liver failure can also cause life-threatening side effects as it progresses. The only cure is a liver transplant.
- Liver cancer. For reasons that aren’t entirely clear, people with chronic hepatitis are more likely to develop primary liver cancer. In fact, healthcare providers consider chronic hepatitis B to be the leading cause of liver cancer. Liver cancer itself is one of the leading causes of death in people with chronic hepatitis B.
Diagnosis and Tests
How is hepatitis B diagnosed?
A healthcare provider will ask you about your symptoms and physically examine you. They might ask about your health history, any history of liver disease in your family or other factors that might make you more susceptible to viral hepatitis.
As you might not have symptoms or any known risk factors, the only way to find out for sure if you have hepatitis B is by testing your blood. Specific blood tests can tell your healthcare provider all they need to know about your condition, such as:
- If you have an acute or chronic infection.
- If you’ve been infected in the past.
- If you’ve developed immunity to the virus.
- If the infection is interfering with your liver function.
After diagnosis, your provider may want to order additional tests to check how your liver is doing. They might want to look at radiographic images of your liver tissues. In some cases, they might want to take a small sample to examine in the lab (liver biopsy).
If you’ve only recently been exposed to HBV and the virus is still incubating in your body, it might not show up on a blood test yet. A healthcare provider may not be able to tell right away if you’ve been infected, but they can still treat you preventatively.
Management and Treatment
What treatment is available for hepatitis B?
A healthcare provider may offer you different treatment options based on the status of the infection.
If you have reason to believe you or your child has recently been exposed to the virus, a healthcare provider might suggest prophylactic treatments to help prevent the infection from taking hold. These treatments include:
- Vaccination. Healthcare providers recommend an immediate dose of the hepatitis B vaccine if you haven’t had it yet, preferably within 24 hours of exposure. You’ll need two more doses over the next six months to become fully vaccinated against the virus.
- Hepatitis B immune globulin (HBIG). HBIG is a substance made from human blood containing naturally-produced antibodies to the hepatitis B virus. It’s given as a shot to help prevent infection in people who’ve recently been exposed to the virus.
These treatments are very effective in preventing babies born to parents with chronic hepatitis B from becoming infected. Infants who receive these treatments shortly after birth have a good prognosis, and they can safely breastfeed (chestfeed).
There’s no specific medication to treat an acute hepatitis B infection, and many people won’t need any treatment. But if you’re having severe symptoms, a healthcare provider might monitor you for complications and offer supportive care, such as:
Treatment for chronic infection
Several medications are available to treat chronic hepatitis B, but they may not be appropriate for everyone. A healthcare provider will recommend treatment based on your condition and risk factors. Your treatment plan may include:
A healthcare provider treating you for chronic hepatitis B will monitor your liver health through regular checkups and testing, ideally every six months. They’ll look for signs of active liver disease that may be affecting your liver’s functioning.
Tests may include:
- Blood tests.
- Imaging tests.
- Elastography (organ stiffness scan).
Healthcare providers have found that current medications for hepatitis B are most effective for people who show signs of active liver disease. This may be only 25% of people diagnosed with chronic hepatitis B, according to the World Health Organization (WHO).
Current medications help boost your immune system and slow down the rate at which the virus reproduces itself. They don’t kill the virus completely, but they can help keep your liver as healthy as possible for as long as possible. They include:
- Immune modulator drugs. Immune modulators, also known as interferons, include peginterferon alfa-2a and interferon apfa-2b. These are synthetic versions of the antibodies our bodies produce to fight infections. They’re given by injection for a course of six to 12 months. They’re prescribed for some adults and as a first-line treatment for children.
- Oral antiviral medications. Antivirals taken by mouth are the most potent medications for suppressing HBV. Your provider might recommend one or several based on who you are and how you respond. First-line antivirals include tenofovir disoproxil or tenofovir alafenamide and entecavir. Most people who begin these medications will continue them for life.
Whether or not you’re taking medication for hepatitis B, you’ll need to take steps to protect your liver from further harm throughout your life. Healthcare providers particularly recommend that you avoid alcohol and maintain a healthy, balanced diet.
Alcohol use and metabolic factors such as a high BMI and high triglycerides are two of the leading causes of liver inflammation outside of infection. When you already have chronic hepatitis, it’s best to limit alcohol, sugar and fat intake to minimize inflammation.
If chronic hepatitis leads to complications such as cirrhosis and liver failure or liver cancer, you might need to have surgery to remove part or all of your liver. Your liver can regenerate itself after a partial resection, as long as enough healthy tissue remains.
If too much of your liver is diseased or failing, however, you’ll need a liver transplant to replace it. Most donated livers come from recently deceased people, and there’s a long waiting list for these. But you can skip the wait if you’re able to find a living liver donor.
How can I reduce my risk of hepatitis B infection?
The best way to prevent infection is vaccination. If you’re vaccinated against the virus, you won’t have to worry about accidental exposure in your day-to-day life. However, it does take about six months to complete the three doses of the hepatitis B vaccine.
In the short-term, you can reduce your risk by:
- Practicing safe sex. If you don’t know whether your partner is infected, use a latex or polyurethane condom.
- Not sharing personal items that might be exposed to blood, such as toothbrushes, razors, medical equipment or needles.
- Planning ahead for travel abroad. If you plan to travel to regions where the rate of infection is relatively high, schedule your vaccinations for before you go.
- Prophylactic treatment. If you think you may have recently been exposed, you can reduce your risk of infection by receiving a dose of vaccine and hepatitis B immune globulin within 24 hours.
How can I prevent spreading the infection to others?
If you have active hepatitis B, you can help protect others from infection by:
- Getting diagnosed. You may not have symptoms of liver disease, but if it’s possible you may have been exposed to the virus through your job or your community, get tested. The sooner you learn about an infection, the better prepared you’ll be to take care of yourself and protect those you work and live with.
- Practicing safe sex. Share your diagnosis with your sexual partners and encourage them to get vaccinated. If they’ve already been exposed, encourage them to get prophylactic treatment. In the meantime, use a latex or polyurethane condom for protection.
- Practicing safe needle use. If you use needles to inject intravenous drugs, make sure to dispose of them safely and wash your hands thoroughly afterward.
- Planning ahead for childbirth. Most maternity healthcare providers will test you for hepatitis B infection, but if you already have a diagnosis, be sure to let them know. They’ll plan ahead to treat your baby immediately after birth to protect them against infection.
Outlook / Prognosis
Is hepatitis B curable?
If you only have a temporary, acute infection, chances are good your immune system will overcome it shortly. Once you’ve recovered from an acute infection, you won’t get it again. A blood test can tell you if you’ve overcome the virus and become immune.
If you don’t overcome it during the acute phase of infection, you’ll develop a chronic infection, which is lifelong. Chronic hepatitis B isn’t curable, but it’s manageable with treatment. A blood test can tell you if you need treatment for a chronic infection.
How often is hepatitis B fatal?
Death from acute hepatitis B is rare. The death rate from chronic hepatitis B is approximately 15%. About 25% of people who become chronically infected as children die of the disease. About 25% of chronic hepatitis B infections lead to liver cancer.
How should I take care of myself while living with chronic hepatitis B?
If you have chronic hepatitis B, it’s very important to stay connected with a qualified healthcare provider, such as a gastroenterologist or a hepatologist (liver specialist). Your provider will keep track of the progress of your disease and advise you on treatment and self-care.
- Go for regular check-ups with your provider every six months or as directed. Check-ups will include various liver tests to monitor the disease and watch for complications.
- Check with your provider before taking any new medicine, including herbal medicines. Some herbs may be harmful to your liver, or they may not mix with your other medications.
- Avoid drinking alcohol and follow a healthy diet to manage your body weight. Alcohol and overweight can add unnecessary stress to your liver.
- Protect yourself from other liver infections. If you haven’t been vaccinated for hepatitis A, get the vaccine. Get tested for hepatitis C and get treatment if you have it. Hepatitis C is curable.
A note from Cleveland Clinic
Most people who get hepatitis B recover shortly on their own. But if you develop a chronic infection, hepatitis B is lifelong. There’s no cure yet for hepatitis B, but regular testing and treatment can minimize the damage it does. Most people can expect to live full, long lives.
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