Gonorrhea is a sexually transmitted disease caused by the transmission of a bacteria. Like many other STDs, gonorrhea can hide from the immune system and an infected person can remain infected indefinitely, although the person may not always be contagious. In addition, the consequences of being infected by gonorrhea are less serious than those caused by syphilis, although the disease can cause sterility if untreated.
Once the infection sets in, it causes the membranes around the urethra to hemorrhage, causing a burning sensation when urinating. In addition, if untreated, pus will start to accumulate and leak from the penis. Females are often completely asymptomatic as the sores only affect the interior surfaces of the reproductive system, but do suffer from vaginal discharge or pelvic pain in most cases.