People who have been treated for trichomoniasis can get it again. About 1 in 5 people get infected again within 3 months after receiving treatment. To avoid getting reinfected, all sex partners should get treated with antibiotics at the same time. Wait to have sex again until everyone has been treated and any symptoms go away (usually about a week). Get checked at 3 months to make sure you have not been infected again, or sooner if your symptoms come back before then.

Trichomoniasis is a sexually transmitted infection (STI) caused by a parasite. The parasite is spread most often through vaginal, oral, or anal sex. It is one of the most common STIs in the United States and affects more women than men. It is easily treated with antibiotics, but many women do not have symptoms. If left untreated, trichomoniasis can raise your risk of getting HIV.
^ Epstein, Aaron; Roy, Subir (2010). "Chapter 50: Vulvovaginitis". In Goodwin, T. Murphy (ed.). Management of Common Problems in Obstetrics and Gynecology (5th ed.). Wiley-Blackwell. p. 228. ISBN 978-1405169165. Archived from the original on 2017-02-15. In 80% of cases, the diagnosis of trichomoniasis is confirmed by microscopic examination of saline wet mount, with the observation of motile trichominondas; their shape is "football-like" with moving flagella.

^ Epstein, Aaron; Roy, Subir (2010). "Chapter 50: Vulvovaginitis". In Goodwin, T. Murphy (ed.). Management of Common Problems in Obstetrics and Gynecology (5th ed.). Wiley-Blackwell. p. 228. ISBN 978-1405169165. Archived from the original on 2017-02-15. In 80% of cases, the diagnosis of trichomoniasis is confirmed by microscopic examination of saline wet mount, with the observation of motile trichominondas; their shape is "football-like" with moving flagella.


^ Kissinger P, Mena L, Levison J, Clark RA, Gatski M, Henderson H, et al. (December 2010). "A randomized treatment trial: single versus 7-day dose of metronidazole for the treatment of Trichomonas vaginalis among HIV-infected women". Journal of Acquired Immune Deficiency Syndromes. 55 (5): 565–71. doi:10.1097/qai.0b013e3181eda955. PMC 3058179. PMID 21423852.
For 95-97% of cases, infection is resolved after one dose of metronidazole.[26][35] Studies suggest that 4-5% of trichomonas cases are resistant to metronidazole, which may account for some “repeat” cases.[33][9] Without treatment, trichomoniasis can persist for months to years in women, and is thought to improve without treatment in men.[9] Women living with HIV infection have better cure rates if treated for 7 days rather than with one dose.[31][36]
^ Vos T, et al. (GBD Study 2013 Collaborators) (August 2015). "Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013". Lancet. 386 (9995): 743–800. doi:10.1016/s0140-6736(15)60692-4. PMC 4561509. PMID 26063472.
People who have been treated for trichomoniasis can get it again. About 1 in 5 people get infected again within 3 months after receiving treatment. To avoid getting reinfected, all sex partners should get treated with antibiotics at the same time. Wait to have sex again until everyone has been treated and any symptoms go away (usually about a week). Get checked at 3 months to make sure you have not been infected again, or sooner if your symptoms come back before then.
Trichomoniasis (trich) infection is spread when you have sex with an infected partner. Many women and most men do not have any symptoms of trich. If symptoms appear, they usually start within 1 week after a person is infected. But it may take up to a month for symptoms to appear. In most cases, trich should be treated to prevent transmitting this sexually transmitted infection (STI) to others and to prevent some problems that can happen if you are pregnant. You and your sex partner(s) should be treated for trich at the same time, to avoid reinfecting each other.
For 95-97% of cases, infection is resolved after one dose of metronidazole.[26][35] Studies suggest that 4-5% of trichomonas cases are resistant to metronidazole, which may account for some “repeat” cases.[33][9] Without treatment, trichomoniasis can persist for months to years in women, and is thought to improve without treatment in men.[9] Women living with HIV infection have better cure rates if treated for 7 days rather than with one dose.[31][36]
Watchful waiting is a period of time during which you and your doctor observe your symptoms or condition without using medical treatment. Watchful waiting isn't appropriate if you think you have trichomoniasis (trich). In most cases, trich should be treated to prevent transmitting this sexually transmitted infection to others and to prevent some problems that can happen if you are pregnant.
A draft sequence of the Trichomonas genome was published on January 12, 2007 in the journal Science confirming that the genome has at least 26,000 genes, a similar number to the human genome. An additional ~35,000 unconfirmed genes, including thousands that are part of potentially transposable elements, brings the gene content to well over 60,000.[16]
For 95-97% of cases, infection is resolved after one dose of metronidazole.[26][35] Studies suggest that 4-5% of trichomonas cases are resistant to metronidazole, which may account for some “repeat” cases.[33][9] Without treatment, trichomoniasis can persist for months to years in women, and is thought to improve without treatment in men.[9] Women living with HIV infection have better cure rates if treated for 7 days rather than with one dose.[31][36]

The parasite passes from an infected person to an uninfected person during sex. In women, the most commonly infected part of the body is the lower genital tract (vulva, vagina, cervix, or urethra). In men, the most commonly infected body part is the inside of the penis (urethra). During sex, the parasite usually spreads from a penis to a vagina, or from a vagina to a penis. It can also spread from a vagina to another vagina. It is not common for the parasite to infect other body parts, like the hands, mouth, or anus. It is unclear why some people with the infection get symptoms while others do not. It probably depends on factors like a person’s age and overall health. Infected people without symptoms can still pass the infection on to others.


^ Epstein, Aaron; Roy, Subir (2010). "Chapter 50: Vulvovaginitis". In Goodwin, T. Murphy (ed.). Management of Common Problems in Obstetrics and Gynecology (5th ed.). Wiley-Blackwell. p. 228. ISBN 978-1405169165. Archived from the original on 2017-02-15. In 80% of cases, the diagnosis of trichomoniasis is confirmed by microscopic examination of saline wet mount, with the observation of motile trichominondas; their shape is "football-like" with moving flagella.
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