Hepatitis B: How It Spreads, Who Is at Risk, and How to Prevent It

Hepatitis is inflammation of the liver: swelling that occurs when tissue is injured or infected, which can damage the liver and affect how well it works. Hepatitis B is a form of viral hepatitis that can cause an acute (short-term) or chronic (long-term) infection. Most people with acute infection recover on their own; some with chronic infection need treatment. Thanks to vaccination, hepatitis B is not very common in the United States, but it is more common in parts of the world such as sub-Saharan Africa and parts of Asia.

How it spreads

The hepatitis B virus spreads through contact with blood, semen or other body fluids of a person who has it.

Who is at higher risk

• babies born to mothers with hepatitis B
• people who inject drugs or share needles, syringes or other drug equipment
• sex partners of people with hepatitis B, especially without latex or polyurethane condoms
• men who have sex with men
• people who live with someone who has hepatitis B, especially if they share razors, toothbrushes or nail clippers
• health care and public safety workers exposed to blood on the job
• people on hemodialysis
• people who have lived in or often travel to places where hepatitis B is common
• people with diabetes, hepatitis C or HIV

Symptoms

Often there are none. Adults and children over 5 are more likely than younger children to have symptoms. Some people with acute infection develop symptoms 2 to 5 months after infection, including:

• dark yellow urine, and gray or clay-colored stools
• diarrhea, nausea or vomiting, and loss of appetite
• fatigue and fever
• joint pain and abdominal pain
• jaundice, yellowing of the eyes and skin

With chronic hepatitis B, symptoms may not appear until complications develop, possibly decades after infection. That is why screening, testing people without symptoms, matters; a provider may recommend it for people at high risk.

Complications

Rarely, acute hepatitis B causes liver failure. Chronic hepatitis B can become a serious disease leading to cirrhosis (scarring of the liver), liver cancer and liver failure. In anyone who has ever had hepatitis B, the virus can reactivate later in life, damaging the liver and causing symptoms.

Diagnosis and treatment

Diagnosis uses a medical history, a physical exam and blood tests, including tests for viral hepatitis. Acute hepatitis B usually needs no treatment, and some people with chronic infection do not either; but if blood tests show the virus may be damaging the liver, antiviral medicines may be needed.

Prevention

The best protection is the hepatitis B vaccine. You can also lower your risk by:

• not sharing needles or other drug equipment
• wearing gloves if you must touch someone else's blood or open sores
• making sure tattoo artists and body piercers use sterile tools
• not sharing toothbrushes, razors or nail clippers
• using a latex condom during sex, or a polyurethane one if either partner is allergic to latex

If you think you have been exposed, see a provider right away. A dose of hepatitis B vaccine, and in some cases hepatitis B immune globulin (HBIG), can prevent infection; both should be given as soon as possible, ideally within 24 hours.

Sources

• MedlinePlus (National Library of Medicine), "Hepatitis B," from the National Institute of Diabetes and Digestive and Kidney Diseases. https://medlineplus.gov/hepatitisb.html