Transmission A<unk>  present in a pregnant woman may be passed on to the infant before or after birth. Risk of transmission per unprotected sexual act with an infected person Known risks Possible Performing oral sex on a man * Throat chlamydia * Throat gonorrhea (25–30%) * Herpes (rare) * HPV * Syphilis (1%) * Hepatitis B (low risk) * HIV (0.01%) * Hepatitis C (unknown) Performing oral sex on a woman * Herpes * HPV * Throat gonorrhea * Throat chlamydia Receiving oral sex—man * Chlamydia * Gonorrhea * Herpes * Syphilis (1%) * HPV Receiving oral sex—woman * Herpes * HPV * Bacterial vaginosis * Gonorrhea Vaginal sex—man * Chlamydia (30–50%) * Crabs * Scabies * Gonorrhea (22%) * Hepatitis B * Herpes (0.07% for HSV-2) * HIV (0.05%) * HPV (high: around 40–50%) * Mycoplasma hominis<unk>  * Mycoplasma genitalium * Syphilis * Trichomoniasis * Ureaplasma<unk>  * Hepatitis C Vaginal sex—woman * Chlamydia (30–50%) * Crabs * Scabies * Gonorrhea (47%) * Hepatitis B (50–70%) * Herpes * HIV (0.1%) * HPV (high; around 40–50%) * Mycoplasma hominis<unk>  * Syphilis * Trichomoniasis * Ureaplasma<unk>  * Hepatitis C Anal sex—insertive * Chlamydia * Crabs * Scabies (40%) * Gonorrhea * Hepatitis B * Herpes * HIV (0.62%) * HPV * Syphilis (14%) * Hepatitis C Anal sex—receptive * Chlamydia * Crabs * Scabies * Gonorrhea * Hepatitis B * Herpes * HIV (1.7%) * HPV * Syphilis (1.4%) * Hepatitis C Anilingus * Amoebiasis * Cryptosporidiosis (1%) * Giardiasis * Hepatitis A(1%) * Shigellosis (1%) * HPV (1%) Bacterial * Chancroid (Haemophilus ducreyi) * Chlamydia (Chlamydia trachomatis) * Gonorrhea (Neisseria gonorrhoeae) * Granuloma inguinale or (Klebsiella granulomatis) * Mycoplasma genitalium * Mycoplasma hominis * Syphilis (Treponema pallidum) * Ureaplasma<unk>  Viral Micrograph showing the viral cytopathic effect of herpes (ground glass nuclear inclusions, multi-nucleation). Pap test. Pap stain. * Viral hepatitis (hepatitis B virus)—saliva, venereal fluids.(Note: hepatitis A and hepatitis E are transmitted via the fecal-oral route; hepatitis C is rarely<unk>  transmittable, and the route of transmission of hepatitis D (only if infected with B) is uncertain, but may include sexual transmission.) * Herpes simplex (Herpes simplex virus 1, 2) skin and mucosal, transmissible with or without visible blisters * HIV (Human Immunodeficiency Virus)—venereal fluids, semen, breast milk, blood * HPV (Human Papillomavirus)—skin and mucosal contact. 'High risk' types of HPV cause almost all cervical cancers, as well as some anal, penile, and vulvar cancer. Some other types of HPV cause genital warts. * Molluscum contagiosum (molluscum contagiosum virus MCV)—close contact * Zika virus Parasites * Crab louse, colloquially known as "crabs" or "pubic lice" (Pthirus pubis). The infestation and accompanying inflammation is Pediculosis pubis * Scabies (Sarcoptes scabiei) * Trichomoniasis (Trichomonas vaginalis), colloquially known as "trich" Main types<unk> s include: * Chlamydia is a<unk>  caused by the bacterium Chlamydia trachomatis. In women, symptoms may include abnormal vaginal discharge, burning during urination, and bleeding in between periods, although most women do not experience any symptoms. Symptoms in men include pain when urinating, and abnormal discharge from their penis. If left untreated in both men and women, chlamydia can infect the urinary tract and potentially lead to pelvic inflammatory disease (PID). PID can cause serious problems during pregnancy and even has the potential to cause infertility. It can cause a woman to have a potentially deadly ectopic pregnancy, in which the egg implants outside of the uterus. However, chlamydia can be cured with antibiotics. * The two most common forms of herpes are caused by<unk>  with herpes simplex virus (HSV). HSV-1 is typically acquired orally and causes cold sores, HSV-2 is usually acquired during sexual contact and affects the genitals, however, either strain may affect either site. Some people are asymptomatic or have very mild symptoms. Those that do experience symptoms usually notice them 2 to 20 days after exposure which lasts 2 to 4 weeks. Symptoms can include small fluid-filled blisters, headaches, backaches, itching or tingling sensations in the genital or anal area, pain during urination, flu like symptoms, swollen glands, or fever. Herpes is spread through skin contact with a person infected with the virus. The virus affects the areas where it entered the body. This can occur through kissing, vaginal intercourse, oral sex or anal sex. The virus is most<unk> s during times when there are visible symptoms, however, those who are asymptomatic can still spread the virus through skin contact. The initial<unk>  and symptoms are usually the most severe because the body does not have any antibodies built up. After the primary attack, one might have recurring attacks that are milder or might not even have future attacks. There is no cure for the disease but there are antiviral medications that treat its symptoms and lower the risk of transmission (Valtrex). Although HSV-1 is typically the "oral" version of the virus, and HSV-2 is typically the "genital" version of the virus, a person with HSV-1 orally CAN transmit that virus to their partner genitally. The virus, either type, will settle into a nerve bundle either at the top of the spine, producing the "oral" outbreak, or a second nerve bundle at the base of the spine, producing the genital outbreak. * The human papillomavirus (HPV) is the most common STI in the United States. There are more than 40 different strands of HPV and many do not cause any health problems. In 90% of cases, the body's immune system clears the<unk>  naturally within two years. Some cases may not be cleared and can lead to genital warts (bumps around the genitals that can be small or large, raised or flat, or shaped like cauliflower) or cervical cancer and other HPV related cancers. Symptoms might not show up until advanced stages. It is important for women to get pap smears in order to check for and treat cancers. There are also two vaccines available for women (Cervarix and Gardasil) that protect against the types of HPV that cause cervical cancer. HPV can be passed through genital-to-genital contact as well as during oral sex. The infected partner might not have any symptoms. * Gonorrhea is caused by bacterium that lives on moist mucous membranes in the urethra, vagina, rectum, mouth, throat, and eyes. The<unk>  can spread through contact with the penis, vagina, mouth, or anus. Symptoms of gonorrhea usually appear two to five days after contact with an infected partner however, some men might not notice symptoms for up to a month. Symptoms in men include burning and pain while urinating, increased urinary frequency, discharge from the penis (white, green, or yellow in color), red or swollen urethra, swollen or tender testicles, or sore throat. Symptoms in women may include vaginal discharge, burning or itching while urinating, painful sexual intercourse, severe pain in lower abdomen (if<unk>  spreads to fallopian tubes), or fever (if<unk>  spreads to fallopian tubes); however, many women do not show any symptoms. Antibiotic resistant strains of Gonorrhea are a significant concern, but most cases can be cured with existing antibiotics. Secondary syphilis * Syphilis is an STI caused by a bacterium. Untreated, it can lead to complications and death. Clinical manifestations of syphilis include the ulceration of the uro-genital tract, mouth or rectum; if left untreated the symptoms worsen. In recent years, the prevalence of syphilis has declined in Western Europe, but it has increased in Eastern Europe (former Soviet states). A high incidence of syphilis can be found in places such as Cameroon, Cambodia, Papua New Guinea. Syphilis<unk> s are increasing in the United States. * Trichomoniasis is a common STI that is caused by<unk>  with a protozoan parasite called Trichomonas vaginalis. Trichomoniasis affects both women and men, but symptoms are more common in women. Most patients are treated with an antibiotic called metronidazole, which is very effective. * HIV (human immunodeficiency virus) damages the body's immune system, which interferes with its ability to fight off disease-causing agents. The virus kills CD4 cells, which are white blood cells that help fight off various<unk> s. HIV is carried in body fluids and is spread by sexual activity. It can also be spread by contact with infected blood, breastfeeding, childbirth, and from mother to child during pregnancy. When HIV is at its most advanced stage, an individual is said to have AIDS (acquired immunodeficiency syndrome). There are different stages of the progression of and HIV<unk> . The stages include primary<unk> , asymptomatic<unk> , symptomatic<unk> , and AIDS. In the primary<unk>  stage, an individual will have flu-like symptoms (headache, fatigue, fever, muscle aches) for about two weeks. In the asymptomatic stage, symptoms usually disappear, and the patient can remain asymptomatic for years. When HIV progresses to the symptomatic stage, the immune system is weakened and has a low cell count of CD4+ T cells. When the HIV<unk>  becomes life-threatening, it is called AIDS. People with AIDS fall prey to opportunistic<unk> s and die as a result.
Sexually transmitted infection
Interstitial cystitis
Vertically transmitted infection
Neurodegenerative disease
Blood-borne disease
Environmental disease
Secondary trauma
Psychogenic disease