Trichomonas
What Is Trichomoniasis? Symptoms, Diagnosis and Treatment
Trichomoniasis is a sexually transmitted infection caused by a parasite called Trichomonas vaginalis. It is treatable. The infection can occur in the vagina and urogenital area in women, and most commonly in the urethra in men.
A substantial proportion of people with the infection may have no symptoms or only mild symptoms. Even without symptoms, the infection can be transmitted to a sexual partner.
How is trichomoniasis transmitted?
Trichomoniasis is most commonly transmitted through sexual contact. A person with no symptoms of infection can also pass the parasite to their partner. Correct and consistent condom use reduces the risk of transmission.
What are the symptoms of trichomoniasis?
Symptoms can vary from person to person. The infection may cause no symptoms at all, and symptoms in those who do develop them can vary in severity.
Possible symptoms in women:
- Increased vaginal discharge or a change in its colour, smell or consistency
- Itching, irritation, redness or tenderness in the genital area
- Pain or burning during urination or sexual intercourse
Possible symptoms in men:
- Burning during urination or after ejaculation
- Itching or irritation in the urethra
- Discharge from the penis
These symptoms are not specific to trichomoniasis; other infections and health conditions can cause similar symptoms. It is therefore not possible to make a diagnosis based on symptoms alone.
How is trichomoniasis diagnosed?
The diagnosis can be confirmed with a laboratory test. Although microscopic examination may be used, its sensitivity may be lower than that of molecular tests. Nucleic acid amplification tests (NAAT/PCR) are among the sensitive methods used to detect T. vaginalis. The appropriate sample type is determined according to the person's circumstances and the test's sample acceptance criteria.
Wellcare STI PCR panel includes Trichomonas vaginalis. For information about the sample type and collection method, and to learn more about the test, you can visit our STI PCR test page.
People diagnosed with trichomoniasis may also need to be evaluated for other sexually transmitted infections, such as HIV, syphilis, chlamydia and gonorrhoea.
How is trichomoniasis treated?
Trichomoniasis is treated with prescription medicines taken by mouth. The CDC recommends metronidazole twice daily for 7 days for women and a single dose of metronidazole for men. The WHO's 2024 recommendation favours metronidazole twice daily for 7 days for adults and adolescents. Treatment appropriate for the individual should be determined by a doctor based on their clinical condition, pregnancy status and current guidelines. Do not take medicines without a doctor's advice.
If symptoms occur during pregnancy, a doctor should be consulted for evaluation and treatment. The CDC states that data indicate metronidazole poses a low risk during pregnancy, while tinidazole should not be used during pregnancy. The treatment decision should be made by a doctor.
Do sexual partners need treatment?
Yes. To prevent reinfection, it is important for current sexual partners to be evaluated and treated at the same time on a doctor's advice. Individuals and their partners should avoid sexual contact until they have completed treatment and any symptoms have resolved.
Is repeat testing needed after treatment?
Sexually active women treated for trichomoniasis are advised to be tested again after approximately 3 months to detect reinfection. There is insufficient evidence to support routine repeat testing in men. If symptoms persist or recur after treatment, medical evaluation should be sought. If an early follow-up test using NAAT/PCR is needed, testing within the first 3 weeks after treatment is completed may produce misleading results due to residual genetic material.
How can trichomoniasis be prevented?
Correct and consistent condom use reduces the risk of sexual transmission of trichomoniasis. Having partners evaluated during the testing or treatment process also helps prevent reinfection. Vaginal douching is not recommended, as it may increase the risk of vaginal infections.