Hepatitis B
Hepatitis B (HBV) is a viral infection that affects the liver. It is considered an STD because it can be transmitted by exchange of infected bodily fluid during unprotected sex. It affects all age groups, and sometimes causes severe liver disease or cancer. It can be fatal in some cases. Like many other viruses, once it gets into the bloodstream, it is there for life; there is no cure. Preventing people from getting infected is the only way to stop its spread. According to the CDC, about 78,000 people were newly infected with HBV in the United States in 2003.
Approximately one in twenty people in North America will get infected with HBV at some time during their lives. Those who are at the greatest risk of being infected are the people who have unprotected sex, share needles, live in a house with someone who is infected, or work in jobs that expose them to bodily fluids like blood or saliva.
The virus is relatively tough and has been known to remain infectious after long periods of time outside of the body. If an infected person spits on a surface and does not properly clean up, there will be infectious viral particles on the surface that can be picked up by the next person to touch that surface. This is one reason why people that live with HBV infected people are at risk of infection.