An STD is a sexually transmitted disease such as HIV, chlamydia, genital herpes, genital warts, gonorrhea, hepatitis, syphilis and trichomoniasis. It is spread through sexual contact. WebMD cautions that an STD can be very severe, sometimes resulting in lifelong treatment; HIV in particular has no cure. STDs are usually caused by bacteria and viruses in blood, semen and vaginal secretions, but genital herpes and warts can spread through skin-to-skin contact.
According to Mayo Clinic, one of the difficulties of recognizing an STD is that each one has different symptoms and many are asymptomatic. Some people show no symptoms whatsoever. To minimize the risk of either contracting an STD or spreading it, WebMD suggests always using a condom during sexual intercourse and never sharing needles when taking drugs; failure to do so is high-risk behavior. Condoms are not a foolproof method, and people should disclose diagnoses of STDs with sexual partners so they understand the risk of infection.
WebMD recommends that people go to doctors if they suspect an infection. Doctors often treat STDs with antibiotics that either cure or lessen the symptoms, reducing the risk of transmission in the process. If you are diagnosed, inform previous and current partners of possible exposure.