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). However, people that share unsterilized needles markedly increase the chance to pass many diseases, including STD’s (especially hepatitis B), to others. Some diseases are not considered to be officially an STD (for example, hepatitis types A, C, E) but are infrequently noted to be transferred during sexual activity. Consequently, some authors include them as STD’s, while others do not. Some lists of STD’s can vary, depending on whether the STD is usually transmitted by sexual contact or only infrequently transmitted.
STDs affect men and women of all ages and backgrounds, including children. Many states require that Child Protective Services be notified if children are diagnosed with an STD. STDs have become more common in recent years, partly because people are becoming sexually active at a younger age, are having multiple partners, and do not use preventive methods to lessen their chance of acquiring an STD. Seniors show a marked increase in STDs in the last few years as many do not use condoms. People can pass STDs to sexual partners even if they themselves do not have any symptoms.
Frequently, STDs can be present but cause no symptoms, especially in women (for example, chlamydia, genital herpes or gonorrhea). This can also occur in some men. Health problems and long-term consequences from STDs tend to be more severe for women than for men. Some STDs can cause pelvic infections such as pelvic inflammatory disease (PID), which may cause a tubo-ovarian abscess. The abscess, in turn, may lead to scarring of the reproductive organs, which can result in an ectopic pregnancy (a pregnancy outside the uterus), infertility or even death for a woman. Human papillomavirus infection (HPV infection), an STD, is a known cause of cancer of the cervix. Many STDs can be passed from a mother to her baby before, during, or immediately after birth.