What it is: Gonorrhea is a bacterial infection, also known as "the clap."

How you get it: Vaginal, anal or oral sex.

Symptoms: Worse for men than women, who may not show any symptoms. Men have extreme pain in urination and discharge from the penis. Women can have some discharge and swollen, tender labia. Sore throat from unprotected oral sex.

Prevention: Avoid intercourse until the person is cured. Condom and spermicide reduce risk, but not entirely.

Treatment: Antibiotics.

Long-term Implications: Untreated gonorrhea can lead to pelvic inflammatory disease (PID) and sterility.