The STI Files: Trichomoniasis

Stat: Trichomoniasis is one of the most common sexually transmitted diseases, mainly affecting people younger than thirty-five years.

What is it exactly? Trichomoniasis ("trick-oh-moe-nye-uh-sis") means an infection with Trichomonas vaginalis, a microscopic parasite found all over the world.

About how many people have it? In the United States, it is estimated that over 7 million people become infected with trichomoniasis each year.

How is it spread? Trichomonas needs a warm and damp environment to live, so it cannot live on toilet seats, but it can live in the vagina, urethra, or bladder. This parasite does not usually grow well in the anus or mouth. Trichomonas is usually sexually transmitted when there is penis-vulva or vulva-vulva contact though it may rarely be passed by sharing damp towels, washcloths, or bathing suits.

What are its symptoms? There is a wide range of symptoms from trichomoniasis. Almost half of infected people will not have any signs at all. If a person does have signs, they usually develop in the first month after infection, but some signs may not show up for six months.

People with vulvas may have the following signs: a bad smelling discharge from the vagina that is yellow or green and may look frothy. This is usually accompanied by vaginal itching and redness, pain during intercourse, pain during urination, or a frequent urge to urinate.

People with penises are less likely to have symptoms than those who have vulvas. If they have symptoms, they may have pain during urination and ejaculation, discharge from the urethra, or a frequent urge to urinate.

How is it diagnosed? By microscopic examination of vaginal discharge and/or a genital exam. If you have a penis, a urine test can be used.

Is it treatable? Yes. A doctor will prescribe antibiotics such as metronidazole or clindamycin for infected people and their sexual partners. This will usually cure the infection, but a second set of antibiotics is sometimes needed. It is also helpful to wear cotton underwear and avoid wearing pantyhose so that there is enough air circulation to keep the area around the vagina dry.

Is it curable? Yes, but you can get it again.

Can it affect fertility? There are no known cases of trichomoniasis effecting fertility. However, it can be passed on to a baby during birth. Very rarely, trichomoniasis will cause changes in PAP smears. In people with penises, this infection can progress to prostatitis (infection of the prostate), urethritis (infection of the urethra), epididymitis (infection of the epididymis), or sores on the penis.

Can it cause death? There are no known cases of trichomoniasis causing death in adults though this infection can increase the risk of preterm delivery, which is risky for infants. The general inflammation caused by any infection, including trichomoniasis, might also increase a person's risk of acquiring HIV infection if they are exposed to HIV or passing HIV to a partner.

How can we protect against it? If you do not have genital contact with other people, your risk of getting trichomonas is very small. If you are having genital contact, it is best to practice safer sex, get regular STI checks with your partners, and limit your number of partners. Having safer sex is a very effective way to prevent the spread of trichomonas during sexual contact which means using latex barriers like condoms, dental dams, and gloves correctly and consistently.

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