Sexually transmitted diseases STDs , or sexually transmitted infections STIs , are infections that are passed from one person to another through sexual contact. The contact is usually vaginal, oral, and anal sex. But sometimes they can spread through other intimate physical contact. STDs can be caused by bacteria , viruses , and parasites. Most STDs affect both men and women, but in many cases the health problems they cause can be more severe for women.
Sexually Transmitted Diseases
The gay bowel syndrome: a common problem of homosexual patients in the emergency department
HIV-1 is more virulent, easily transmitted and is the cause of the vast majority of HIV infections globally. Scientists generally accept that the known strains or groups of HIV-1 are most closely related to the simian immunodeficiency viruses SIVs endemic in wild ape populations of West Central African forests. Using HIV-1 sequences preserved in human biological samples along with estimates of viral mutation rates, scientists calculate that the jump from chimpanzee to human probably happened during the late 19th or early 20th century, a time of rapid urbanisation and colonisation in equatorial Africa. Exactly when the zoonosis occurred is not known. Some molecular dating studies suggest that HIV-1 group M had its most recent common ancestor MRCA that is, started to spread in the human population in the early 20th century, probably between and
Here's how you know if you have contracted a sexually transmitted disease
Since reports of the human immunodeficiency virus HIV began to emerge in the United States in the s, the HIV epidemic has frequently been linked to gay , bisexual , and other men who have sex with men MSM by epidemiologists and medical professionals. The first official report on the virus was published by the Center for Disease Control CDC on June 5, and detailed the cases of five young gay men who were hospitalized with serious infections. It is now well understood that HIV does not only affect the gay community but can also infect anybody, regardless of sex, ethnicity, or sexual orientation.
Print Version pdf icon. The content here can be syndicated added to your web site. Sexually transmitted diseases STDs are diseases that can be passed from one person to another through intimate physical contact and sexual activity. While anyone who has sex can get an STD, sexually active gay, bisexual and other men who have sex with men MSM are at greater risk. Sexual contact includes oral, anal and vaginal sex, as well as genital skin-to-skin contact.