How Is Hepatitis B Transmitted?

The hepatitis B virus is known as a blood-borne virus because it is transmitted from one person to another via blood or fluids contaminated with blood. Another important route of transmission is from an infected mother to a newborn child, which occurs during or shortly after birth.

Direct contract with blood may occur through the use of dirty needles during illicit drug use, inadvertent needle sticks experienced by healthcare workers, or contact with blood through other means. Semen, which contain small amounts of blood, and saliva that is contaminated with blood also carry the virus.

The virus may be transmitted when these fluids come in contact with broken skin or a mucous membrane (in the mouth, genital organs, or rectum) of an uninfected person.

People who are at an increased risk of being infected with the hepatitis B virus include the following:

* Men or women who have multiple sex partners, especially if they don't use a condom

* Men who have sex with men

* Men or women who have sex with a person infected with hepatitis B virus

* People with other sexually transmitted diseases

* People with HIV or hepatitis C

* People who inject drugs with shared needles

* People who receive organ transplants or transfusions of blood or blood products (exceedingly rare these days)

* People who undergo dialysis for kidney disease

* Institutionalized mentally handicapped people and their attendants, caregivers, and family members

* Health care workers who are stuck with needles or other sharp instruments contaminated with infected blood

* Infants born to infected mothers

* People born outside the United States in areas where hepatitis B is common

* People who travel to areas of the world where hepatitis B is common

In some cases, the source of transmission is never known.