Trichomoniasis is a common sexually transmitted infection (STI) that can affect individuals of all genders. Caused by the Trichomonas vaginalis parasite, trichomoniasis is one of the most prevalent STIs worldwide. Though often asymptomatic, it can lead to a range of uncomfortable symptoms, such as irritation, discharge, and discomfort during sexual activity. Fortunately, trichomoniasis is treatable with antibiotics and preventable with safe sexual practices.

In this article, we’ll explore everything you need to know about trichomoniasis, including its causes, symptoms, diagnosis, treatment options, prevention strategies, and how it can impact your health in the long term.

What Is Trichomoniasis?

Trichomoniasis, often referred to as "trich," is a parasitic infection caused by Trichomonas vaginalis, a single-celled organism that thrives in the moist areas of the genitourinary system. It is one of the most common sexually transmitted infections globally, affecting millions of people annually. According to the Centers for Disease Control and Prevention (CDC), about 2.1% of people assigned female at birth and 0.5% of people assigned male at birth in the United States are infected with trichomoniasis.

The parasite primarily infects the genital tract, including the vagina, urethra, and prostate. In women, trichomoniasis is commonly associated with vaginitis, an inflammation of the vagina, while in men, it can lead to urethritis, inflammation of the urethra.

Trichomoniasis Symptoms: What to Look For

Trichomoniasis is often referred to as a "silent" STI because many people infected with the parasite do not show any symptoms. In fact, approximately 70% of people with trichomoniasis remain asymptomatic, making it difficult to detect without proper testing.

When symptoms do occur, they usually appear within 5 to 28 days of exposure to the parasite. These symptoms can vary in severity, but common signs of trichomoniasis include:

Common Symptoms for Women

  • Vaginal discharge: The discharge associated with trichomoniasis is typically thin, frothy, and may have a foul odor. It can be clear, white, yellowish, or greenish in color.

  • Itching and irritation: Women may experience itching or irritation around the vaginal area and the vulva.

  • Pain during urination: A person infected with trichomoniasis may feel a burning or painful sensation when urinating.

  • Painful sexual intercourse: Discomfort or pain during sexual activity is common among individuals with trichomoniasis.

  • Redness or swelling: The genital area may appear red or swollen.

Common Symptoms for Men

  • Penile discharge: Men infected with trichomoniasis may notice a clear, white, or yellow discharge from the penis.

  • Itching or irritation: Men may also experience itching or irritation around the tip of the penis or urethra.

  • Pain during urination: Similar to women, men with trichomoniasis may feel discomfort or pain when urinating.

  • Painful ejaculation: Some men may experience discomfort or pain during ejaculation.

  • Redness around the penis: Red spots or irritation may appear on the genital area.

While these symptoms can be unpleasant, they may subside on their own or with treatment. However, untreated trichomoniasis can lead to complications and recurrent infections.

What Causes Trichomoniasis?

Trichomoniasis is caused by the Trichomonas vaginalis parasite, which is transmitted through sexual contact. The parasite is highly contagious and can be spread through vaginal, anal, or oral sex with an infected person. In some cases, it may also be passed through the sharing of contaminated sex toys.

The parasite thrives in moist environments and can survive in the genitourinary tract for long periods. It primarily infects the vagina and urethra in women, and the prostate and urethra in men. Trichomoniasis is not spread through casual contact, such as hugging, kissing, or sharing utensils.

Risk Factors: Who Is at Risk for Trichomoniasis?

Several factors can increase your likelihood of contracting trichomoniasis. These include:

  • Multiple sexual partners: Having multiple sexual partners increases the risk of exposure to STIs, including trichomoniasis.

  • Unprotected sex: Not using condoms or other barrier methods during sex significantly increases the risk of getting trichomoniasis and other STIs.

  • History of STIs: A person who has previously been infected with another STI, such as chlamydia or gonorrhea, is at greater risk of contracting trichomoniasis.

  • Drug use: Using intravenous drugs that involve sharing needles can increase the risk of trichomoniasis, as it may involve exposure to infected fluids.

  • Low socioeconomic status: Studies have shown that individuals with lower levels of education or those living below the federal poverty line may be at higher risk of contracting STIs, including trichomoniasis.

  • Smoking: Smoking may also increase the risk of trichomoniasis, as it can weaken the immune system and affect the health of the genital tract.

Diagnosing Trichomoniasis

To diagnose trichomoniasis, healthcare providers will typically conduct a physical examination and may request additional tests to confirm the infection. The diagnostic methods for trichomoniasis include:

  • Nucleic acid amplification test (NAAT): This is an FDA-approved test used to detect the presence of Trichomonas vaginalis DNA in urine or vaginal samples. It is highly sensitive, with a 90% detection rate.

  • Microscopic examination: A healthcare provider may take a sample of vaginal discharge or urine and examine it under a microscope for signs of the parasite.

  • Cotton swab test: For women, a healthcare provider may use a cotton swab to collect discharge from the vaginal walls, which will then be tested for the parasite.

  • Urine sample: In some cases, a urine sample may be analyzed to detect the presence of Trichomonas vaginalis.

A positive test result will confirm the diagnosis of trichomoniasis, and additional tests may be performed to check for other STIs, as trichomoniasis is often found in conjunction with conditions like chlamydia and gonorrhea.

Treatment Options for Trichomoniasis

Trichomoniasis is a curable infection, and treatment usually involves the use of oral antibiotics. The two main antibiotics used to treat trichomoniasis are:

  • Metronidazole: This antibiotic is taken in doses of 500 mg twice a day for seven days.

  • Tinidazole: This is another antibiotic, typically taken as a single 2-gram dose.

Both medications work by eliminating the Trichomonas vaginalis parasite, providing relief from symptoms and reducing the risk of complications. It's crucial that both sexual partners receive treatment to avoid reinfection.

In some cases, pregnant individuals are advised to undergo treatment to reduce the risk of premature labor and low birth weight. However, tinidazole is not recommended for use during pregnancy, while metronidazole is considered safe for use in the second trimester and beyond.

Preventing Trichomoniasis

Prevention of trichomoniasis involves adopting safe sexual practices. Here are the key steps to reduce your risk of contracting or spreading trichomoniasis:

  • Abstinence: Refraining from sexual activity until you and your partner are no longer infected can help prevent the spread of trichomoniasis.

  • Consistent condom use: Using condoms during vaginal, anal, and oral sex reduces the risk of trichomoniasis and other STIs. It’s essential to use a new condom for each sexual act and ensure it is applied correctly.

  • Mutual monogamy: Having a single, mutually monogamous sexual partner who has been tested for STIs and is free of trichomoniasis reduces the likelihood of contracting the infection.

Additionally, regular STI screenings are recommended for sexually active individuals, particularly those with multiple partners or who engage in unprotected sex.

Long-Term Health Impacts and Comorbid Conditions

Although trichomoniasis is treatable, untreated infections can lead to serious health complications. If left untreated, trichomoniasis can increase the risk of developing other STIs, including:

  • HIV/AIDS: People with trichomoniasis are at greater risk of acquiring HIV.

  • Pelvic Inflammatory Disease (PID): In women, untreated trichomoniasis can lead to PID, which can cause damage to the reproductive organs, increase the risk of infertility, and contribute to chronic pelvic pain.

  • Epididymitis: In men, trichomoniasis can cause inflammation of the epididymis, the tube at the back of the testicle, leading to pain and potential fertility issues.

  • Prostatitis: This is inflammation of the prostate gland, which can be caused by trichomoniasis in men.

Recurrence of Trichomoniasis

Even after successful treatment, trichomoniasis can return. Studies show that one in five people may get re-infected with trichomoniasis within three months after treatment. This can be due to unprotected sex with an infected partner or not completing the full course of antibiotics.

To prevent reinfection, both partners must be treated simultaneously, and individuals should take steps to practice safe sex going forward.