[1] Sexually transmitted infection (STI) or sexually transmitted disease (STD) (older term: venereal disease (VD) is an infection spread by sex, mainly vaginal intercourse, anal sex, oral sex, or manual sex. STIs often dont initially cause symptoms, risking transmitting them on to others.
STI symptoms/signs may be vaginal discharge, penile discharge, ulcers on or around the genitals, and pelvic pain. Some STIs can cause infertility.
[1] Bacterial STIs are chlamydia, gonorrhea, and syphilis. Viral STIs include genital warts, genital herpes, and HIV/AIDS.[1] Parasitic STIs include trichomoniasis. Most STIs are treatable and curable; of the most common infections, syphilis, gonorrhea, chlamydia, and trichomoniasis are curable, while HIV/AIDS and genital herpes are not curable. Some vaccinations may decrease the risk of certain infections including hepatitis B and few types of HPV. Safe sex practices such as use of condoms, having smaller number of sexual partners, and being in a relationship in which each person only has sex with the other also decreases STIs risk. Comprehensive sex education may also be useful.
Chlamydia is caused by the bacterium Chlamydia trachomatis
[1] Not all STIs are symptomatic, and symptoms may not show right after infection. At times, a disease is carried without symptoms, making higher risk to pass it to others. Depending on the disease, untreated STIs can cause infertility/chronic pain/death.[12]
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