The primary purpose of a hepatitis B test is to diagnose an acute or a chronic liver infection due to the hepatitis B virus. Testing may also be done to detect a previous, resolved hepatitis B infection or sometimes to monitor the treatment of your infection. The CDC recommends hepatitis B testing for:
Hepatitis B testing is typically done through a blood sample, but for further evaluation or unclear test results, your doctor may order a liver biopsy. A liver biopsy can also help determine if liver damage has occurred and the severity of the damage.
While there’s no preparation needed for blood tests, liver biopsy preparation may include undergoing a physical exam and completing a medical history. You may also need to stop taking medications that affect bleeding, avoid eating or drinking anything for up to eight hours before the procedure, and arrange for someone to drive you home afterward.
The most common risk factors for becoming infected with hepatitis B reported in 2017 were injection drug use, men who have sex with men, and multiple sex partners. It’s also common for household members in close contact with people infected with hepatitis B to become infected. Babies born of mothers with hepatitis B are also at a high risk of getting the virus.
Hepatitis B can survive outside the body and still cause infection for at least seven days. This puts health care and public safety workers at an increased risk of getting hepatitis B from occupational exposure to blood and body fluids contaminated with blood infected with the virus. Direct contact with an open wound on a person with hepatitis B can cause you to become infected. However, hepatitis B can’t be spread through coughing, sneezing, hugging, kissing, hand-holding, food or water, sharing eating utensils, or breastfeeding.
There are several variations of viral hepatitis. The three most common types are hepatitis A, B, and C. Hepatitis A is the mildest form, while hepatitis B and C are more serious. Rare forms of the virus include hepatitis D and E, but both variations are very uncommon in the U.S. Perinatal hepatitis B is a specific variation of hepatitis B that’s directly passed to infants from mothers infected with the virus.
Stages of hepatitis B include active and chronic infection. When you first become infected, you’re in the acute stage. In this stage, your symptoms may range from nonexistent to liver failure. There are three phases of acute infection, including the prodromal, preicteric, and icteric phases, and each has differing symptoms.
Most adults recover from acute infection and have no further problems. However, if the virus remains in your blood for more than six months, you enter the chronic stage. In this stage, you’re at a higher risk of developing liver cancer. Infants and young children are at a greater risk of developing chronic hepatitis B.
If symptoms of acute hepatitis B occur, they typically last several weeks, but they can persist for up to six months. When symptoms occur, they begin an average of 90 days after exposure to the virus. Acute hepatitis B symptoms may differ depending on which of the three stages you’re in.
The prodromal phase is the early stage, and symptoms may include:
The next stage is the preicteric phase, and symptoms may include:
During the final icteric phase, previous symptoms may subside, but nausea and/or vomiting, and anorexia may worsen. You may also develop irritated skin lesions, and jaundice, which is the yellowing of the skin and eyes, will likely occur.
Sometimes acute hepatitis B infections go away on their own, but some people develop a chronic infection. Symptoms of chronic hepatitis B may be similar to acute hepatitis, but most people don’t have any symptoms or any evidence of liver disease unless the virus progresses. If the virus progresses to cirrhosis, which is when your liver becomes severely scarred, you may develop symptoms of liver failure, including:
Hepatitis B testing is complex but should be done to detect the virus before it causes liver damage. If you think you’ve been exposed to the virus or you have symptoms that indicate you may have the virus, your doctor begins your hepatitis B diagnosis by conducting a thorough physical examination, while you describe your symptoms and medical history.
Next, blood samples are taken from a vein, and your doctor orders diagnostic tests to see if you have abnormal levels of certain enzymes in your blood. Lab technicians look for specific markers, including:
The purpose of these blood tests is to look for a marker or series of markers that indicate whether you’re infected and whether you have acute or chronic hepatitis B. Blood tests can also be used to determine whether you’re immune to hepatitis B due to vaccination or immunity from prior infection, or if you’re vulnerable to infection and should be vaccinated. You may also need a series of blood tests to gauge your liver function.
If your blood test results are unclear, you have symptoms that aren’t typically associated with hepatitis B, or there’s evidence of chronic liver disease, your doctor may order a liver biopsy. During this biopsy, a small sample of your liver tissue is removed and sent to a lab for analysis. This analysis determines whether you have hepatitis B and how much scar tissue is on your liver.
Besides being tested by your doctor, there are also walk-in laboratories, health clinics, STD testing sites, and other health care facilities that provide testing for hepatitis B. If you need help finding a testing facility, the CDC maintains a database of testing centers that screen for hepatitis B and other STDs. For private, more discreet testing, you may also purchase an at-home hepatitis B test kit at some pharmacies or other local stores and online, direct from the manufacturer.
If you have an acute hepatitis B infection, it may resolve itself or become chronic. Treatment isn’t recommended for acute infection, and there aren’t any medications available to aid in treatment. However, you may receive supportive care to treat the symptoms and even be hospitalized if the symptoms are severe.
If your infection becomes chronic, there are several medications available to suppress the virus, and you must be monitored regularly to prevent liver damage. If left untreated, chronic hepatitis B can cause cirrhosis or liver cancer, leading to liver failure or death. A previously resolved case of hepatitis B can reactivate, meaning it can suddenly come back and be worse than before. Treatment may slow the progression of the virus. It’s important to speak to a medical provider to learn which treatment options are right for you.
While there currently isn’t a cure for Hepatitis B, it’s preventable with a series of vaccinations, usually given in three doses over six months. Since 1991, the Advisory Committee on Immunization Practices has recommended that all infants receive the hepatitis B vaccine to help eliminate the virus. Other people who should get a hepatitis B vaccine include:
If you haven’t been vaccinated and you’re exposed to hepatitis B, you may avoid infection by getting a hepatitis B immune globulin shot within 24 hours of exposure. It’s common for you also to be given the first dose of the hepatitis B vaccine at that time.
Easy to use at-home test kits for hepatitis B are available online with simple instructions. Once you receive your test kit, you must first activate it. You use a lancet to prick the tip of your finger to collect a blood sample, which you pack back into the box the kit arrived in. Place this box in the postage-paid mailer and send it to the laboratory for testing. You’ll receive confidential test results typically within a few days through a secure online account.
At-home test kits may be available over-the-counter from local pharmacies and other stores. Pharmacies that don’t carry test kits in the store may allow you to order one and have it shipped to your home. You can also order test kits directly from the manufacturer online or by phone or mail.
According to the CDC, the results of your hepatitis B blood test vary depending on whether the infection is a new acute infection or a chronic infection. Depending on the antigens or antibodies found in your blood sample, a positive result can mean varying things. A positive result for:
Like positive results, negative results can also mean various things depending on what’s found in your blood sample. A negative result for:
To date, there’s not a cure for hepatitis B. Once infected, you could carry the virus for the rest of your life, which can lead to cirrhosis or cancer of the liver, and death. If you’ve previously been infected with hepatitis B and your body cleared the virus, it develops a natural immunity, and you can’t get infected again. If you’re exposed to hepatitis B and you’re unvaccinated, you can avoid infection by getting a hepatitis B immune globulin shot within 24 hours.
The time it takes to receive your test results vary, depending on where you get tested and whether they have an in-house laboratory or they mail it out for testing. Typically, it takes a week or two to receive your results if your sample must be mailed to an external laboratory for testing. After submitting a sample from an at-home test kit, the analyzing laboratory generally has results with a few days.
For patients living with chronic hepatitis B infection, the Hepatitis B Research Network provides links to clinical trials and recent studies involving the virus.