Sexually transmitted infections
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This reference extract addresses Sexually transmitted infection, a related subject. It does not cover every part of Sexually transmitted infections.. The article introduction is reproduced here, so you do not need to leave MedAtlas to read it. It may not match the latest official medical guidance.
A sexually transmitted infection (STI), also known as a sexually transmitted disease (STD) or venereal disease (VD), is an infection that is spread by sexual activity, especially vaginal intercourse, anal sex, oral sex, or sometimes manual sex. STIs often do not initially cause symptoms, which results in a risk of transmitting them to others. The term sexually transmitted infection is generally preferred over sexually transmitted disease or venereal disease, as it includes cases with no symptomatic disease. Symptoms and signs of STIs may include vaginal discharge, penile discharge, ulcers on or around the genitals, and pelvic pain. Some STIs can cause infertility.
Bacterial STIs include chlamydia, gonorrhea, and syphilis. Viral STIs include genital warts, genital herpes, and HIV/AIDS. Parasitic STIs include trichomoniasis. Most STIs, such as syphilis, gonorrhea, chlamydia and trichomoniasis, are treatable and curable. Others, such as HIV/AIDS and genital herpes, are not curable. Some vaccinations have been known to decrease the risk of certain infections including hepatitis B and a few types of HPV. Using condoms, having a smaller number of sexual partners, and being in a relationship in which each person only has sex with the other are all safe sex practises that decreases the risk of contracting STIs. Comprehensive sex education may also be useful.
STI diagnostic tests are usually easily available in the developed world, but they are often unavailable in the developing world. There is often shame and stigma associated with STIs. In 2015, STIs (excluding HIV) resulted in 108,000 deaths worldwide. Globally, in 2015, about 1.1 billion people had STIs other than HIV/AIDS. About 500 million have syphilis, gonorrhea, chlamydia or trichomoniasis. At least an additional 530 million have genital herpes, and 290 million women have human papillomavirus. Historical documentation of STIs in antiquity dates back to at least the Ebers Papyrus (c. 1550 BCE) and the Hebrew Bible/Old Testament (8th/7th C. BCE).
How this connects to MD Dermatology
Infectious-disease biology depends on organism properties, entry route, replication, tissue tropism and host response. Infection must be distinguished from colonization or contamination. Laboratory test timing, specimen quality and local epidemiology affect interpretation; antimicrobial choice requires current susceptibility and professional guidance.
Text credit: Wikipedia contributors, “Sexually transmitted infection”, original article · authors & revision history · CC BY-SA 4.0. Unmodified opening extract, accessed 24 September 2026. This Wikipedia-derived section is provided under CC BY-SA 4.0; the independent MedAtlas notes and design are separate works.
Sexually transmitted infections · visual study map
Scalable vector illustration. Labeled conceptual map, not a precise anatomical, histological or diagnostic image.The wording in this learning map is adapted from the attributed Wikipedia background section below (CC BY-SA 4.0).
What the underlying subject studies
At postgraduate and higher-specialty level, begin with normal anatomy and physiology of the relevant organ system, then compare distinct disease mechanisms, their evidence base and the limitations of available investigations.
How mechanisms and evidence connect
Advanced study requires evidence appraisal, multidisciplinary interpretation and a clear distinction between established facts, hypotheses and research findings. Procedural, diagnostic and prescribing skills must be learned under an accredited program.
How to develop a sound explanation
Identify the scope of this topic within the named specialty, connect it to the applicable patient population and formulate a structured question that can be answered using current specialty literature and supervised teaching.
References and verification (optional)
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