Hepatitis A is acquired through ingesting fecally contaminated water or food or engaging in sexual practices involving anal contact. Injection drug users who share unclean needles also are at risk. The hepatitis B virus is found in blood, semen, vaginal secretions and saliva. This highly contagious virus is spread through sexual contact, sharing contaminated drug needles, blood transfusions, and piercing the skin with contaminated instruments. Hepatitis B may damage the liver, putting people at risk for cirrhosis and liver cancer.
Most infections clear up by themselves within four to eight weeks.
Hepatitis B is the only STD for which there is a vaccine. Although many public health officials recommend the vaccine for children, adolescents and young adults, it is not widely administered, due in part to the stigmatization of STDs and the cost of the three-part vaccine. Another virus-induced liver disease. An estimated 40 million Americans have genital herpes, with 500,000 new cases each year. Approximately two-thirds of people who are infected do not know they have genital herpes, either because they have no symptoms or because their symptoms are so mild they go unnoticed.