Trichomoniasis is a common sexually transmitted infection (STI) affecting millions of people annually worldwide. It is often called “trich.”
Trichomoniasis: What It Is and How It Spreads
Trichomoniasis is caused by a single-celled parasite called Trichomonas vaginalis. This parasite primarily infects the lower genital tract in women, including the vulva, vagina, cervix, and urethra, and the urethra in men. Humans are the only known hosts for T. vaginalis. The parasite requires a moist environment to survive and is very fragile outside the human body.
Transmission of Trichomonas vaginalis through inanimate objects like towels, toilet seats, or hot tubs is considered extremely rare or virtually impossible. While the parasite can survive for a few hours on moist surfaces, it quickly loses viability once it dries or is exposed to significant temperature changes. Therefore, direct, intimate contact is almost exclusively necessary for its spread.
The primary and most common way trichomoniasis spreads is through direct sexual contact. This includes vaginal-penile intercourse, vaginal-vaginal contact, and in some cases, other forms of genital touching. The parasite typically spreads from a penis to a vagina, or from a vagina to a penis, during sexual activity. It is not common for the parasite to infect other body parts, such as the hands, mouth, or anus.
Recognizing the Symptoms
Many individuals infected with trichomoniasis, particularly men, may not experience any noticeable symptoms. In fact, about 70% of people with the infection remain asymptomatic, which contributes to its quiet spread. When symptoms do occur, they can vary from mild irritation to more severe inflammation and typically appear between 5 to 28 days after exposure, though sometimes much later.
In women, symptoms can include a change in vaginal discharge, which might be thin, frothy, or have a white, yellow, or greenish appearance with a strong, foul, or “fishy” odor. Other signs can involve itching, burning, soreness, or redness around the genitals. Discomfort during urination or pain during sexual intercourse are also common.
Men who experience symptoms may notice irritation or itching inside the penis. They might also have a mild discharge from the penis or experience a burning sensation during urination or after ejaculation.
Diagnosis and Treatment Options
Diagnosing trichomoniasis typically involves a healthcare provider assessing a person’s symptoms and conducting specific tests. A physical exam may be performed, which for women can include a pelvic examination where a healthcare provider might observe signs like a “strawberry cervix” in some cases. Laboratory tests are essential to confirm the diagnosis.
For women, a sample of vaginal fluid is often collected and examined under a microscope in a “wet mount” to look for the motile Trichomonas vaginalis parasite. For men, a urine sample or a urethral swab might be used for testing. Nucleic acid amplification tests (NAATs) are also available and are highly sensitive, identifying the parasite’s genetic material.
Trichomoniasis is curable with prescription medication, usually a course of antibiotics. Metronidazole or tinidazole are commonly prescribed. It is crucial for the infected individual to complete the entire course of medication as prescribed, even if symptoms improve. All sexual partners of an infected person should also be tested and treated simultaneously to prevent re-infection and further spread. Individuals undergoing treatment should abstain from sexual activity until both they and their partners have completed treatment and all symptoms have resolved, typically for about one week.
Preventing Trichomoniasis
Preventing trichomoniasis primarily involves practicing safer sexual habits, as it is almost exclusively transmitted through sexual contact. Consistent and correct use of condoms during every sexual encounter significantly reduces the risk of transmission. Condoms act as a barrier, preventing the exchange of bodily fluids that can carry the parasite.
Limiting the number of sexual partners can also lower the risk of exposure to trichomoniasis and other STIs. Engaging in a mutually monogamous relationship with a partner who has been tested and is known to be uninfected is another effective prevention strategy. Open and honest communication with sexual partners about sexual health history and STI status is a valuable step towards prevention.
Regular STI testing is important, especially for sexually active individuals or those with new partners, even if no symptoms are present. Early detection and treatment prevent further transmission and potential complications. If diagnosed, ensuring all sexual partners receive treatment is essential to break the cycle of infection and prevent re-infection.