What are the causes of Hepatitis B?

Hepatitis B is caused by the Hepatitis B virus and is transmitted when blood, semen, or other bodily fluid infected with the virus enters the body of an uninfected person. Ways people can become infected include:

  • Sex with an infected partner
  • Sharing syringes, needles, or other drug-injection paraphernalia
  • Birth (spread from an infected mother to her baby during birth)
  • Sharing items such as toothbrushes or razors with an infected person
  • Direct contact with the blood or open sores of an infected person
  • Exposure to blood from needle sticks or other sharp instruments

Many of those who have the chronic Hepatitis B virus may not realize they even have the disease since they neither look nor feel sick. That said, they may still develop serious health problems later on and can still spread the virus to others.

Nearly two thirds of the acute Hepatitis B cases in the U.S. are the result of sexual contact amongst adults which is the most common mode of transmission. Spread via bodily fluids like blood, semen and vaginal fluids, Hepatitis B is 50 to 100 times more infectious than HIV.

Hepatitis B is not typically transmitted via water or food like Hepatitis A, but has been known to spread to young children whose food has been pre-chewed by a person with the disease. It is not transmitted by hugging, kissing, holding hands, coughing, sneezing, breastfeeding or by sharing eating utensils.

What are the symptoms of Hepatitis B?

Some people may exhibit symptoms of acute Hepatitis B, but a majority of the people with chronic Hepatitis B can remain symptom-free for 20-30 years. Serious liver damage can occur in 15-25% of the people with chronic Hepatitis B such as cirrhosis (scarring) of the liver, liver failure and liver cancer. Some people still may not know they have liver disease caused by Hepatitis B due to lack of symptoms – only blood tests for liver function may reveal abnormalities.

Symptoms of acute Hepatitis B virus infection will typically manifest in older children and adults. About 70% of adults and children over the age of 5 with the infection will develop symptoms.

Symptoms (if they manifest themselves) of acute Hepatitis B can include:

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

Typically, symptoms develop an average of 90 days (range: 60 – 150 days) after exposure to the virus, but they can appear anytime between 6 weeks and 6 months after initial exposure.

Symptoms may only last a few weeks, but sometimes can persist for up to 6 months. Many infected with the Hepatitis B virus show no symptoms, but they can still spread the disease.

Visit your doctor if you think you may have Hepatitis B. Since symptoms are often not seen nor experienced, the disease usually needs to be diagnosed via blood tests. Such tests search for the presence of antigens and antibodies to help determine if you have:

  • Acute or chronic infection
  • Recovered from infection
  • An immunity to Hepatitis B
  • The potential to benefit from vaccination  

What is the Hepatitis B Vaccine?

The Hepatitis B vaccine is a series of inoculations that stimulate the body’s immune system to shield against the Hepatitis B virus. Once the vaccine is administered, antibodies are produced to shield the person against the virus. Antibodies are found in the bloodstream and are produced when the body detects a virus invading it. Once manufactured, the antibodies will stay in the body and fight an infection – like Hepatitis B – if the person is exposed to the virus in the future.

Who should get vaccinated?

The Hepatitis B vaccine is typically administered in a sequence of 3-4 shots during a 6-month period.

It is recommended for:

  • All infants, beginning with the first dose of Hepatitis B vaccine at birth
  • All children and adolescents younger than 19 years of age who have not been vaccinated
  • Sexually active individuals who are not in a long-term, mutually monogamous relationship
  • People whose sex partners have Hepatitis B
  • Men who have sexual contact with other men
  • Persons seeking evaluation or treatment for a sexually transmitted disease
  • People who share syringes, needles, or other drug-injection paraphernalia
  • People who have close household contact with someone infected with the Hepatitis B virus
  • Health care and public safety workers at risk for exposure to blood or blood-contaminated body fluids while on the job
  • People with end-stage renal disease, including predialysis, hemodialysis, peritoneal dialysis, and home dialysis patients
  • Residents and staff of facilities for developmentally disabled persons
  • People with chronic liver disease
  • People with HIV infection
  • Travelers to regions with moderate-to-high rates of Hepatitis B
  • People aged 19 – 59 with diabetes
  • Anyone who wishes to be protected from Hepatitis B virus infection

To proactively reach those at risk for Hepatitis B, vaccination is also recommended for people in or seeking treatment from the following:

  • Sexually transmitted disease treatment facilities
  • HIV testing and treatment facilities
  • Health care settings targeting services to men who have sex with men
  • Facilities providing drug-abuse treatment and prevention services
  • Correctional facilities
  • Health care settings targeting services to injection drug users
  • Chronic hemodialysis facilities and end-stage renal disease programs
  • Institutions and nonresidential day care facilities for developmentally disabled persons

    When should a person get the Hepatitis B vaccine series?

    • During childhood and adolescence
    • At birth and complete the vaccine series by 6-18 months of age
    • Before a child reaches 19 years of age, especially those who have not yet gotten the vaccine should also be vaccinated  (“Catch-up” vaccination is recommended for children and adolescents who were never vaccinated or who did not get the entire vaccine series)
    • Adulthood – especially any adult who is at risk for Hepatitis B virus infection (those who want to be vaccinated should talk to their doctor about receiving the vaccine series)