From the Guidelines
Trichomonas vaginalis can indeed lay dormant in the body without causing acute symptoms, and this is particularly common in men who often serve as asymptomatic carriers, as well as in women who may harbor the infection without noticeable symptoms. This phenomenon is supported by the fact that most men infected with T. vaginalis do not have symptoms, while others may have non-gonococcal urethritis (NGU) 1. Women, on the other hand, may have symptoms characterized by a diffuse, malodorous, yellow-green discharge with vulvar irritation, but some may have minimal or no symptoms 1. The ability of T. vaginalis to persist asymptomatically is likely due to its ability to adapt to changes in vaginal pH and evade immune responses, allowing it to survive in the moist environments of the genital tract.
Some key points to consider about asymptomatic Trichomonas vaginalis infection include:
- The infection can persist for months or even years without causing noticeable symptoms
- Asymptomatic carriers, particularly men, can transmit the infection to their sexual partners
- Women may also harbor the infection without symptoms, with studies suggesting that 10-50% of infected women remain asymptomatic
- The standard treatment for trichomoniasis is a single 2-gram dose of metronidazole or tinidazole taken orally, or alternatively, 500 mg of metronidazole twice daily for 7 days 1
- Both sexual partners should be treated simultaneously to prevent reinfection, even if one partner has no symptoms
It is essential to note that diagnosis of vaginal trichomoniasis is usually performed by microscopy of vaginal secretions, but this method has a sensitivity of only about 60%--70% 1. Culture is the most sensitive commercially available method of diagnosis, and PCR testing may also be available from commercial laboratories that have developed their own PCR tests 1. Testing is recommended for anyone with symptoms or who has had sexual contact with an infected person.
From the Research
Trichomonas Infection Characteristics
- Trichomonas vaginalis can infect the genitourinary tract and has been isolated from virtually all genitourinary structures 2.
- Asymptomatic disease is common in both men and women, thus screening for disease is important 2.
- Infection with T vaginalis could have an important role in transmission and acquisition of HIV 2.
Dormancy and Recurrence
- Most persons infected with TV are asymptomatic, and high rates of retest positive are found among TV infected persons after single dose metronidazole treatment 3.
- Persistent and recurrent TV infections are frequent in women, potentially due to the lack of routine screening recommendations for this pathogen, the chronic nature of some infections, and drug resistance 4.
- Treatment failure can range from 7-10 % and even higher among HIV+ women, suggesting that the infection can lay dormant without acute illness 3.
Treatment and Management
- Metronidazole and tinidazole are two oral drugs that are effective against trichomoniasis, but metronidazole resistance is an emerging problem 2, 4.
- Single-dose 2-g oral secnidazole is a newly approved treatment for trichomoniasis, with favorable pharmacokinetics and efficacy 5.
- Tinidazole therapy has been shown to be effective in treating metronidazole-resistant vaginal trichomoniasis, with a cure rate of 92% in one study 6.