Sexually transmitted diseases are infections that are commonly spread by sexual contact. [1] The medical subarea is also called venereology (Latin: venus – "love" and Greek: logos – "science") [2] [3]

Viral and bacterial germs as well as microorganisms such as fungi and single-cell organisms might cause infections. Parasites like crab lice can inhabit the skin of the genital area and cause irritations. [1] [4]

Large parts of society still regard sexuality which is not within heteronormative or monogamous constellations as negative. Due to this moral assessment, venereal diseases are also a big taboo which prevents open and sensible dealings with them. Since the access to adequate information as well as effective methods of treatment is complicated, infections can spread successfully. Even so, there are therapy modalities which can cure or at least control infections. In case they remain unnoticed and/or untreated, they can cause lasting damage like infertility or cancer and decrease the quality of living of those affected. [5] [6]

Since the list of all diseases which can be transmitted by physical and mucosal contact would go beyond the scope of this chapter, only the most important ones will be discussed here: Infections like Chlamydia, gonorrhea, syphilis, herpes, water warts, and vaginal mycosis, HIV/AIDS, hepatitis B and HPV.