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Sexually Transmitted Diseases
Sexually transmitted diseases (STDs, venereal diseases) are among the most common infectious diseases in the United States today. STDs are sometimes referred to as sexually transmitted infections, since these conditions involve the transmission of an infectious organism between sex partners. More than 20 different STDs have been identified, and about 19 million men and women are infected each year in the United States, according to the CDC (2010).
Depending on the disease, the infection can be spread through any type of sexual activity involving the sex organs, the anus, or the mouth; an infection can also be spread through contact with blood during sexual activity. STDs are infrequently transmitted by other types of contact (blood, body fluids or tissue removed from an STD infected person and placed in contact with an uninfected person).