How common is chronic HBV infection in the United States?
An estimated 800,000–1.4 million persons in the United States have chronic HBV infection. Chronic infection is an even greater problem globally, affecting approximately 350 million persons. An estimated 620,000 persons worldwide die from HBV-related liver disease each year.

Hepatitis means inflammation of the liver. Toxins, certain drugs, some diseases, heavy alcohol use, and bacterial and viral infections can all cause hepatitis. Hepatitis is also the name of a family of viral infections that affect the liver; the most common types in the United States are hepatitis A, hepatitis B, and hepatitis C.

Hepatitis B is a contagious liver disease that results from infection with the hepatitis B virus. It can range in severity from a mild illness lasting a few weeks to a serious, lifelong illness. Hepatitis B is usually spread when blood, semen, or another body fluid from a person infected with the hepatitis B virus enters the body of someone who is not infected. This can happen through sexual contact with an infected person or sharing needles, syringes, or other drug-injection equipment. Hepatitis B can also be passed from an infected mother to her baby at birth.

Hepatitis B can be either acute or chronic. Acute hepatitis B virus infection is a short-term illness that occurs within the first 6 months after someone is exposed to the hepatitis B virus. Acute infection can — but does not always — lead to chronic infection. Chronic hepatitis B virus infection is a long-term illness that occurs when the hepatitis B virus remains in a person’s body. Chronic hepatitis B is a serious disease that can result in long-term health problems, and even death.

What are the symptoms of acute hepatitis B?

Symptoms of acute hepatitis B, if they appear, can include:

• Fever
• Fatigue
• Loss of appetite
• Nausea
• Vomiting
• Abdominal pain
• Dark urine
• Clay-colored bowel movements
• Joint pain
• Jaundice (yellow color in the skin or the eyes)

How soon after exposure to hepatitis B will symptoms appear?

On average, symptoms appear 90 days (or 3 months) after exposure, but they can appear any time between 6 weeks and 6 months after exposure.

How long do acute hepatitis B symptoms last?

Symptoms usually last a few weeks, but some people can be ill for as long as 6 months.

Can a person spread hepatitis B without having symptoms?

Yes. Many people with hepatitis B have no symptoms, but these people can still spread the virus.

What are the symptoms of chronic hepatitis B?

Some people have ongoing symptoms similar to acute hepatitis B, but most individuals with chronic hepatitis B remain symptom free for as long as 20 or 30 years. About 15%–25% of people with chronic hepatitis B develop serious liver conditions, such as cirrhosis (scarring of the liver) or liver cancer. Even as the liver becomes diseased, some people still do not have symptoms, although certain blood tests for liver function might begin to show some abnormalities.

How will I know if I have hepatitis B?

Talk to your health professional. Since many people with hepatitis B do not have symptoms, doctors diagnose the disease by one or more blood tests. These tests look for the presence of antibodies or antigens and can help determine whether you:

• have acute or chronic infection
• have recovered from infection
• are immune to hepatitis B
• could benefit from vaccination

How serious is chronic hepatitis B?

Chronic hepatitis B is a serious disease that can result in long-term health problems, including liver damage, liver failure, liver cancer, or even death.