Gonorrhea, also called “the clap,” is a type of sexually transmitted disease (STD) caused by bacteria. The bacteria that cause gonorrhea (Neisseria gonorrhoeae) thrive in moist areas of the body in both women and men. Gonorrhea can be spread through any kind of sexual contact (vaginal, oral or anal) with an infected person. Ejaculation is not necessary to spread gonorrhea. Physical contact with the infected area may also spread the disease (e.g., touching the genitals and then touching the inside of the mouth or an eye). It is not spread by kissing.

In women, the gonorrhea bacteria usually enter the body during vaginal intercourse. The cervix (entrance to the uterus) is the most likely site of a gonorrhea infection in women and may become inflamed. Bacteria may also reach the urethra (tube leading to the bladder) and cause inflammation there. Gonorrhea bacteria may also lodge in the vagina and glands near the entrance to the vagina. This can result in painful swelling of the gland. However, this type of gonorrhea is uncommon in adult women.

In men, gonorrhea bacteria are transmitted into the urethra during intercourse, where the bacteria cause inflammation to occur. The most common indication of a gonorrhea infection in men is discharge from the penis and a burning sensation when urinating.

Gonorrhea can also occur in the anus, either from anal sex or by bacteria transmitted to the anus from the genitals. Infection of the anus is rare in heterosexual men and most often occurs in men and women who engage in receptive anal intercourse. People may also contract a gonorrhea infection in the throat by having oral sex with an infected partner. If a person touches an infected area and then touches the eyes, gonorrhea may spread to the eyes, a condition called gonococcal conjunctivitis. However, the gonorrhea bacteria can only survive for brief periods of time away from moist surfaces. The bacteria cannot survive or be transmitted from inanimate objects or surfaces.

In extreme cases when gonorrhea is left untreated, infection can spread to other parts of the body, causing inflammation of areas such as the brain and spinal chord (meningitis), heart (endocarditis) or joints (arthritis). In women, gonorrhea can spread to the upper reproductive organs where it can cause pelvic inflammatory disease (PID). PID that is not treated in a timely manner can scar the tissue within the fallopian tubes and can cause infertility. In men, gonorrhea can cause epididymitis, a condition that causes painful swelling of the scrotum. Epididymitis can also lead to infertility. Gonorrhea can also increase the risk of becoming infected with human immunodeficiency virus (HIV), the virus that leads to acquired immune deficiency syndrome (AIDS). Some studies suggest that a history of gonorrhea may increase a man's risk of developing prostate cancer. This risk may be even higher if the man has a history of multiple gonorrhea infections. 

More than 330,000 cases of gonorrhea were reported to the U.S. Centers for Disease Control and Prevention (CDC) in 2004, the last year for which figures are available. However, the CDC estimates that this number accounts for only half of the nation’s gonorrhea cases since many of the cases go unreported. Because gonorrhea in women is frequently asymptomatic, an important element in controlling the spread of gonorrhea is to screen women who are at risk for STDs. African-Americans are most affected by the disease, with almost 20 times the incidence in 2004 than was found among white Americans. Other minority groups, including Hispanics, may also have a higher rate of incidence. For the past four consecutive years, the gonorrhea rate has been higher for women than men.