Hepatitis B is an infection caused by the HBV virus that leads to inflammation of the liver. It can cause acute symptoms such as fever, nausea, vomiting, joint pain, and yellowing of the skin and eyes.
Hepatitis B spreads through contact with contaminated blood or body fluids such as semen or vaginal secretions. Unprotected sex is a major risk factor, which is why hepatitis B is classified as a sexually transmitted infection (STI).
Treatment depends on the stage of the disease. In acute hepatitis B, rest, hydration, and dietary care are usually recommended. In chronic hepatitis B, treatment typically involves prescription medications prescribed by a hepatologist, infectious disease specialist, or primary care doctor.
Main symptoms
The most common early symptoms of hepatitis B include:
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Low-grade fever
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Skin rashes
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Joint and muscle pain
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Fatigue
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Nausea or vomiting
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Abdominal pain
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Loss of appetite
Other signs such as yellowing of the skin and eyes, dark urine, and pale stools indicate that the disease is progressing and causing liver damage.
In chronic hepatitis B, most people do not develop symptoms, but the virus remains in the body and can still be transmitted.
The incubation period for hepatitis B ranges from 2 to 6 months, so signs and symptoms of acute infection often appear 1 to 3 months after exposure.
Complications of hepatitis B
Hepatitis B virus can cause direct toxic injury to the liver or trigger an immune response that results in liver inflammation.
In some cases, the infection becomes chronic and may progress to cirrhosis of the liver.
Online symptom checker
To assess the risk of having hepatitis B, select the symptoms you are experiencing in the tool below:
This symptom checker is for guidance only. It does not provide a diagnosis and does not replace an evaluation by a hepatologist, infectious disease specialist, or primary care doctor.
How a diagnosis is confirmed
Hepatitis B is diagnosed by a hepatologist, infectious disease specialist, or primary care doctor based on symptoms, medical history, sexual history, drug use, occupation, and a physical exam.
To confirm the diagnosis, blood tests are used to detect the presence of HBV and measure its viral load. These results are important to guide treatment decisions.
Hepatitis B test results
To confirm hepatitis B infection, blood tests are performed to check for antigens (Ag) and antibodies (anti). Possible results include:
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HBsAg positive: indicates hepatitis B infection
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HBeAg positive: shows active viral replication, meaning a higher risk of transmission
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Anti-HBs positive: indicates immunity or recovery from hepatitis B, often after vaccination
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Anti-HBc positive: indicates prior exposure to the hepatitis B virus
Additional blood tests may be ordered to evaluate liver function, such as AST (TGO), ALT (TGP), GGT, and bilirubin. In some cases, a liver biopsy may be recommended to assess the extent of damage, predict disease progression, and determine treatment needs.
How it's transmitted
Hepatitis B is transmitted through contact with blood, semen, vaginal secretions, or breast milk from an infected person.
1. Horizontal transmission
Horizontal transmission occurs through direct contact with infected blood or fluids, or by sharing contaminated items such as needles, syringes, or equipment used for tattoos, piercings, or acupuncture.
Sharing personal items like razors, toothbrushes, or manicure/pedicure tools can also spread hepatitis B.
Unprotected sex, whether vaginal, anal, or oral, is another common way the virus spreads, since hepatitis B is present in semen, vaginal fluids, and saliva. This is why it is considered an STI.
Although the virus can be found in saliva, it is rarely spread through kissing or sharing utensils unless there are open sores in the mouth.
2. Vertical transmission
Vertical transmission occurs less frequently and happens when a mother passes hepatitis B to her baby during childbirth or breastfeeding.
Types of hepatitis B
The main types of hepatitis B are:
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Acute hepatitis B: liver inflammation lasting from a few weeks up to 6 months, usually with clearance of the virus during this time
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Chronic hepatitis B: persistence of HBsAg in the blood for more than 6 months
Chronic hepatitis B can cause ongoing liver damage, increase the risk of cirrhosis, and raise the likelihood of developing liver cancer.
Treatment options
Treatment for hepatitis B should always be guided by a hepatologist, infectious disease specialist, or primary care doctor. It generally involves rest, hydration, dietary adjustments, and avoiding alcohol.
If necessary, medications may be prescribed to relieve symptoms such as fever, headaches, nausea, or vomiting.
For chronic hepatitis B, treatment includes avoiding alcohol, following a low-fat diet, and taking antiviral or immunomodulatory drugs such as interferon or lamivudine to prevent irreversible liver damage. These medications may need to be taken for life.
Can hepatitis B be cured?
Most cases of acute hepatitis B resolve on their own, as the immune system produces antibodies that eliminate the virus.
In some people, however, the infection becomes chronic, and the virus stays in the body permanently.
With proper treatment, a person may become an inactive carrier, meaning the virus remains but does not cause active liver disease. In some cases, people with chronic hepatitis B may eventually be cured after many years of treatment.
Prevention of hepatitis B
Prevention measures for hepatitis B include:
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Receiving all 3 doses of the hepatitis B vaccine
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Using condoms during all sexual activity
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Avoiding sharing personal items like toothbrushes, razors, or manicure tools
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Avoiding sharing needles, syringes, or sharp instruments
It is also important to ensure that all equipment for tattoos, piercings, or acupuncture is properly sterilized.
Hepatitis B vaccine
The hepatitis B vaccine is the most effective way to prevent infection. It should be given at birth (within 12 hours), followed by doses at 2 months and 6 months of age, for a total of 3 doses.
Adults who were not vaccinated as children can still receive the vaccine, including pregnant women starting in the second trimester.
The effectiveness of vaccination can be confirmed with an Anti-HBs blood test, which is positive when immunity has been achieved.