Does Hepatitis B cause symptoms? Causes and immunity screening for Hep B

January 31, 2024

Hepatitis B is a contagious liver infection caused by the hepatitis B virus (HBV). It is transmitted through contact with infected blood or other bodily fluids.


HBV infections can be serious, as they may increase the risk of complications like liver disease if left unaddressed. However, it can be difficult to know whether you have an HBV infection, as there may not be any symptoms.


While many people are vaccinated for hepatitis B during childhood, not everyone receives the vaccine, and immunity can wane over time.


So, how do you know if you’re protected against hepatitis B? Here’s what you need to know about hepatitis B symptoms, causes and immunity testing.


What are the symptoms of hepatitis B?

Symptoms of chronic hepatitis B can range from mild to severe. In the earliest phase of HBV infection, known as the acute phase, some people do have flu-like symptoms, such as:

  • Fatigue
  • Fever
  • Loss of appetite 
  • Nausea
  • Vomiting
  • Abdominal pain
  • Joint pain
  • Jaundice (yellowing skin and eyes)


However, many people have no symptoms at all during acute HBV infection. In fact, it’s estimated that asymptomatic acute infection occurs in up to 70% of adults who contract the virus.


In most cases, the infection resolves on its own and the virus is cleared from the body. However, when HBV remains in the body after acute infection, chronic hepatitis B may develop. This occurs in about 5% to 10% of adult cases. Chronic hepatitis B has similar symptoms to acute hepatitis B, but it can eventually progress to serious liver damage, including cirrhosis or liver cancer over time. Treatments are available and may require long-term dosing to keep the virus in check. This is why it’s important to talk to your healthcare provider if you’re experiencing any of these symptoms.


Understanding the causes of hepatitis B: Who is most at risk?

Hepatitis B is spread through contact with infected blood and bodily fluids. Activities like unprotected sex, sharing needles, living with an infected person and childbirth are common ways hepatitis B is transmitted.


You are at higher risk of contracting hepatitis B if you:

  • Live with someone infected with hepatitis B
  • Have multiple sexual partners
  • Have a sexually transmitted infection
  • Are a man who has sex with men
  • Inject drugs or share needles
  • Have household contact with someone who injects drugs
  • Are on kidney dialysis
  • Have HIV
  • Travel to countries where hepatitis B is common
  • Are an infant born to a mother infected with HBV


Who should be tested for hepatitis B?

Since symptoms do not always occur with hepatitis B infection, testing is important to detect the virus. The Centers for Disease Control and Prevention (CDC) recommends hepatitis B testing for all adults and anyone who may be concerned about contact with infected blood or bodily fluids.


Specifically, the CDC recommends testing for:

  • All adults aged 18 years and older once in their lifetime
  • All pregnant people early during each pregnancy
  • Infants born to pregnant people with HBV infection
  • Any individual who requests hepatitis B testing


To find out if you’re protected from HBV, Labcorp OnDemand's Hepatitis B Immunity Test can help you determine your immunity status. Our immunity test is not intended to diagnose a current active hepatitis B infection, but it can detect immunity from either past resolved HBV infection or hepatitis B vaccination.


What do hepatitis B antibody test results mean?

Even if you were vaccinated for hepatitis B as a child, immunity can decrease over time. Labcorp OnDemand’s Hepatitis B Immunity Test can help determine whether you still have protection. This knowledge empowers you to discuss next steps, like a potential booster shot, with your healthcare provider.


Knowing your immunity status empowers you to take action to prevent infection if needed.