Hepatitis B is caused by the Hepatitis B virus. Often, no symptoms occur, but symptoms can include fatigue, fever, and lack of appetite. Hepatitis B attacks the liver and eventually leads to liver damage or failure. Hep B is found in saliva, blood, semen, and urine and can be spread through intimate touching and kissing, vaginal, oral, and anal sex, as well as through needle sharing. In some people, the infection clears on its own, but others may remain infected and contagious for life. Hepatitis B can be prevented by a series of vaccines. Condoms provide limited protection. A blood test can be used to diagnose Hepatitis B.