Trichomoniasis is a common sexually transmitted infection (STI) caused by the single-celled parasite, Trichomonas vaginalis. This infection is transmitted through sexual contact, though most infected individuals experience no noticeable symptoms, making routine testing important for control. Even without symptoms, the presence of the parasite can increase the risk of transmitting or acquiring other STIs, including HIV. Because symptoms can be subtle or mimic other conditions, laboratory testing is the only reliable way to confirm a diagnosis of trichomoniasis.
The Status of At-Home Testing
At-home options for trichomoniasis testing allow for screening outside of a traditional clinical setting. Historically, at-home options involved sample collection kits, requiring the user to collect a vaginal swab or urine sample and mail it to a certified laboratory for analysis. These mail-in kits utilize the same high-sensitivity laboratory methods as in-clinic tests, often providing results within a few days.
A recent development is the authorization of a fully at-home, nonprescription diagnostic test for women. This product is a single-use, molecular test that detects the parasite’s genetic material and delivers results within approximately 30 minutes, without needing to mail the sample to a lab. This device uses a self-collected vaginal swab and a small powered testing unit to perform a highly accurate analysis, similar to a simplified version of clinical equipment.
Clinical trials demonstrated that this rapid at-home test correctly identified positive Trichomonas vaginalis samples with an accuracy of approximately 97.8 percent. While these advances offer greater convenience and privacy, any positive result from an at-home test or collection kit requires follow-up with a healthcare provider for treatment.
Clinical Diagnostic Methods
In healthcare facilities, clinicians primarily rely on accurate laboratory procedures to detect the parasite. The gold standard for identifying Trichomonas vaginalis is the Nucleic Acid Amplification Test (NAAT), which detects the genetic material of the organism. NAATs are significantly more sensitive than older methods, with some assays demonstrating a detection rate near 98 percent, making them the preferred choice for both symptomatic and asymptomatic screening.
NAAT testing can be performed on various sample types, including vaginal swabs, endocervical swabs, or urine, which are then sent to a lab for processing. This molecular method is effective because it can identify a small number of organisms, even in patients who have no outward symptoms.
Another method still sometimes used is direct microscopy, often called a wet mount or wet prep. This involves examining a fresh sample of vaginal discharge under a microscope to look for the characteristic jerky movement of the live parasites. However, the wet mount’s sensitivity is low (typically 44 to 68 percent) because parasites quickly lose motility and the test relies heavily on the reader’s skill. Due to its poor performance, especially for screening, the wet mount is not recommended as the primary diagnostic tool.
Accessing Testing and Treatment Options
Individuals seeking testing have multiple accessible avenues beyond the at-home options. Testing is routinely available through primary care physicians, gynecologists, specialized sexual health clinics, and local health departments. Urgent care centers and telehealth providers also frequently offer testing services for trichomoniasis and other STIs.
Sexual health clinics and public health services are often excellent resources, providing confidential testing and sometimes offering low-cost or free options for those who are uninsured or underinsured. Telehealth services can facilitate the process by offering remote consultations and coordinating the necessary lab work, which may include sending a lab order for an in-person collection or arranging a mail-in kit.
A positive diagnosis is followed by a straightforward and effective treatment regimen. The infection is treated with prescription oral antibiotics, typically metronidazole or tinidazole. Treatment is generally simple, often requiring just a single dose of medication to eliminate the parasite.
All sexual partners must also receive treatment simultaneously to prevent immediate re-infection (known as partner treatment). Following treatment, patients should abstain from sexual activity for about one week until the medication has taken effect. To ensure the infection is completely cleared, a follow-up test, known as a test of cure, is often recommended for women three months after treatment.