Risk Factors and Transmission:

Depending on the type of hepatitis virus, there are different ways that people can acquire hepatitis. In the United States, the main ways that people contract hepatitis are:

• Hepatitis A. Through contaminated food and water
• Hepatitis B. Through sexual contact
• Hepatitis C. Through contact with infected blood, usually by sharing drug injection needles and syringes

Hepatitis A

The hepatitis A virus is excreted in feces and transmitted by ingesting contaminated food or water. An infected person can transmit hepatitis to others if they do not take strict sanitary precautions, such as thoroughly washing hands before food preparation

People can become infected with hepatitis A by:

• Eating or drinking food or water contaminated with hepatitis A virus. Contaminated fruits, vegetables, shellfish, ice, and water are common sources of hepatitis A transmission.
• Engaging in sexual practices (oral-anal contact) that may facilitate ingestion of fecal matter.

People at high risk for hepatitis A infection include:

• International travelers. Hepatitis A is the hepatitis strain people are most likely to encounter in the course of international travel to developing countries.
• Day care employees and children. Many cases of hepatitis A occur among day care employees and children who attend day care. Risks can be reduced if hygienic precautions are used, particularly when changing babies and handling diapers.
• People living in a household with someone who has hepatitis A
• Men who have sex with men
• Users of illegal drugs

Hepatitis B

The hepatitis B virus is transmitted through blood, semen, and vaginal secretions. Situations that can cause hepatitis B transmission include:

• Sexual contact with an infected person (using a condom can help reduce risk)
• Sharing needles and drug injection equipment
• Sharing personal items, (such as toothbrushes, razors, and nail clippers), with an infected person
• Having direct contact with blood of an infected person, through touching open wounds or needlesticks
• During birth, an infected mother can spread the hepatitis B virus to her baby.

The CDC recommends routine testing for chronic hepatitis B virus (HBV) infection for the following high risk groups:

• Persons born in regions with high rates of hepatitis B infection. Hepatitis B is very common in Asian and Pacific Island countries. In the United States, 1 in 10 Asian Americans is chronically infected with the hepatitis B virus. Other regions with high rates of HBV prevalence include Africa, the Middle East, Eastern Europe, South and Central America, and the Caribbean. US-born people not vaccinated as infants whose parents were born in these regions should also be screened for HBV.
• People who use injected drugs or who share needles
• Men who have sex with men
• People receiving chemotherapy or immunosuppressive therapy for certain medical conditions including cancer, organ transplantation, or rheumatologic or gastoenterologic disorders
• Donors of blood, organs, or semen
• Hemodialysis patients
• All pregnant women and infants born to mothers infected with HBV
• People who have sex with an infected person or who live in a household with an infected person
• Health care workers and others exposed to blood products and needlestick devices.
• People infected with HIV

Other people at high risk for hepatitis B virus infection include:

• People who have multiple sex partners
• International travelers to countries with high rates of hepatitis B
• People who received a blood transfusion or received a blood clotting product prior to 1987, when better procedures were implemented to screen donors and blood products for the hepatitis B virus.

Hepatitis C

The hepatitis C virus is transmitted by contact with infected human blood.

• Most people are infected through sharing needles or other drug injection equipment.
• Less commonly, hepatitis C is spread through sexual contact, sharing household items such as razors or toothbrushes, or through birth to a mother infected with hepatitis C.

People at high risk for hepatitis C include:

• Current and former drug injection users (this group is most at risk)
• People who received a blood transfusion, blood product, or organ before 1992 when procedures were implemented to screen blood for hepatitis C
• People who received a blood clotting product prior to 1987, when screening procedures were implemented
• Hemodialysis patients
• People who have had tattooing or body piercing performed with non-sterile instruments
• Healthcare workers who may be exposed to needlesticks
• People infected with HIV
• Babies born to mothers infected with hepatitis C