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3. SEXUALLY TRANSMITTED DISEASE: HERPES

Genital herpes is caused by two viruses: Herpes simplex type 1 (HSV1), which usually affects your mouth as cold sores, and herpes simplex type 2 (HSV2), which mainly targets your genitals. Sexual contact can spread your partner’s oral herpes to your genitals or her genital herpes to your mouth. The virus can be spread even if you—or your partner—don’t have any signs of it. Wearing condoms can help protect you, but not completely: They’re only 80 percent effective for preventing herpes transmission, says Dr. Ghanem. That’s partly because the virus can live on parts of your skin that aren’t covered by the condom.

Signs of herpes

Up to 70 percent of people infected with the virus don’t have symptoms. If you do, you may notice blisters or ulcers on your genitals, or just feel some burning and itching. When first infected, some patients will develop fevers, chills, swollenlymph nodes, headaches, and fatigue.

How to detect herpes

Have your doctor take a look at any suspicious sores.

How to treat herpes

There’s no cure for genital herpes, but antiviral drugs can ease your symptoms, according to the CDC.