This document discusses sexually transmitted infections (STIs), providing key facts and details. It notes that 448 million new curable STIs like syphilis and gonorrhea occur yearly. Some STIs have no symptoms but can still spread and cause complications. Untreated STIs can lead to infertility, pregnancy complications, cervical cancer, and increased HIV risk. The document outlines common bacterial, viral and parasitic STIs as well as STI syndromes and recommends abstinence or consistent condom use to prevent transmission.