STIS

Sexually transmitted infections (STIs) are infections spread primarily through sexual contact, including vaginal, anal, and oral sex. Some STIs can also be transmitted through blood or from mother to child during childbirth. Many STIs are preventable through safe-sex practices, vaccination, and regular testing, and early treatment reduces complications and transmission.

Common STIs include chlamydia, gonorrhea, syphilis, human immunodeficiency virus (HIV), hepatitis B, human papillomavirus (HPV), herpes simplex virus (HSV), and trichomoniasis. Symptoms, when they occur, can vary and many infections are asymptomatic. Possible signs include unusual discharge, burning with urination, genital sores or warts, itching, or flu-like symptoms. Because asymptomatic infections are common, regular screening is important for at‑risk individuals and partners.

Diagnosis relies on infection-specific tests, such as nucleic acid amplification tests for chlamydia and gonorrhea, serology or rapid tests for HIV and syphilis, swabs or urine tests, and cervical or other site sampling for HPV-related testing. Timely testing helps prevent complications and reduces onward transmission.

Treatment varies by infection. Many bacterial STIs (such as chlamydia, gonorrhea, syphilis, and trichomoniasis) are curable with antibiotics when detected early. HIV is managed with antiretroviral therapy, which controls the virus but is not curable. There is no cure for HSV or HPV, but vaccines (for HPV and hepatitis B) and antiviral therapies can manage symptoms and prevent spread.

Prevention includes consistent condom or barrier use, vaccination (HPV, hepatitis B), risk-reduction strategies, regular testing, prompt treatment of partners, and, for HIV, pre-exposure prophylaxis (PrEP) for those at risk. Pregnancy requires prenatal STI screening to prevent mother-to-child transmission. Public health efforts emphasize confidentiality, education, stigma reduction, and contact tracing.