Athlete's foot is a fungal infection of the skin, not an STI.

Chlamydia is the most commonly reported STI in the United States, with over 1.3 million cases reported in 2018.

Gonorrhea is caused by the bacterium Neisseria gonorrhoeae and can be treated with antibiotics.

Syphilis is caused by the spirochete Treponema pallidum and can lead to serious health problems, including damage to the heart, brain, and nervous system, if left untreated.

HIV is caused by the human immunodeficiency virus and can lead to AIDS (acquired immunodeficiency syndrome), a life-threatening condition that weakens the immune system.

The best way to prevent STIs is to abstain from sexual activity, use condoms correctly every time you have sex, and get vaccinated against HPV and hepatitis B.

Chlamydia can cause a variety of symptoms, including painful urination, discharge from the penis or vagina, and swollen lymph nodes.

Gonorrhea can cause a variety of symptoms, including painful urination, discharge from the penis or vagina, and swollen lymph nodes.

Syphilis can cause a variety of symptoms, including a painless sore on the genitals, anus, or mouth, swollen lymph nodes, and a rash on the palms of the hands and soles of the feet.

HIV can cause a variety of symptoms, including fever, fatigue, weight loss, and other flu-like symptoms.

Chlamydia is treated with antibiotics.

Gonorrhea is treated with antibiotics.

Syphilis is treated with antibiotics.

HIV is treated with antiviral drugs.

The best way to protect yourself from STIs is to abstain from sexual activity, use condoms correctly every time you have sex, and get vaccinated against HPV and hepatitis B.