Trichomoniasis
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Trichomoniasis is a common sexually transmitted disease (STD)
that affects both women and men, although symptoms are more common in
women.
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Trichomoniasis is the most common curable STD in young, sexually
active women. An estimated 7.4 million new cases occur each year in
women and men.
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Trichomoniasis is caused by the single-celled protozoan parasite,
Trichomonas vaginalis. The vagina is the most common site of
infection in women, and the urethra (urine canal) is the most common
site of infection in men. The parasite is sexually transmitted through
penis-to-vagina intercourse or vulva-to-vulva (the genital area outside
the vagina) contact with an infected partner. Women can acquire the
disease from infected men or women, but men usually contract it only
from infected women.
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Most men
with trichomoniasis do not have signs or symptoms; however, some men may
temporarily have an irritation inside the penis, mild discharge, or
slight burning after urination or ejaculation.
Some women
have signs or symptoms of infection which include a frothy, yellow-green
vaginal discharge with a strong odor. The infection also may cause
discomfort during intercourse and urination, as well as irritation and
itching of the female genital area. In rare cases, lower abdominal pain
can occur. Symptoms usually appear in women within 5 to 28 days of
exposure.
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The genital
inflammation caused by trichomoniasis can increase a woman’s
susceptibility to HIV infection if she is exposed to the virus. Having
trichomoniasis may increase the chance that an HIV-infected woman passes
HIV to her sex partner(s).
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Pregnant
women with trichomoniasis may have babies who are born early or with low
birth weight (less than five pounds).
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For both men
and women, a health care provider must perform a physical examination
and laboratory test to diagnose trichomoniasis. The parasite is harder
to detect in men than in women. In women, a pelvic examination can
reveal small red ulcerations (sores) on the vaginal wall or
cervix.
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Trichomoniasis can usually be cured with the prescription drug,
metronidazole, given by mouth in a single dose. The symptoms of
trichomoniasis in infected men may disappear within a few weeks without
treatment. However, an infected man, even a man who has never had
symptoms or whose symptoms have stopped, can continue to infect or
re-infect a female partner until he has been treated. Therefore, both
partners should be treated at the same time to eliminate the parasite.
Persons being treated for trichomoniasis should avoid sex until they and
their sex partners complete treatment and have no symptoms.
Metronidazole can be used by pregnant women.
Having
trichomoniasis once does not protect a person from getting it again.
Following successful treatment, people can still be susceptible to
re-infection.
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The surest
way to avoid transmission of sexually transmitted diseases is to abstain
from sexual contact, or to be in a long-term mutually monogamous
relationship with a partner who has been tested and is known to be
uninfected.
Latex male
condoms, when used consistently and correctly, can reduce the risk of
transmission of trichomoniasis.
Any genital
symptom such as discharge or burning during urination or an unusual sore
or rash should be a signal to stop having sex and to consult a health
care provider immediately. A person diagnosed with trichomoniasis (or
any other STD) should receive treatment and should notify all recent sex
partners so that they can see a health care provider and be treated.
This reduces the risk that the sex partners will develop complications
from trichomoniasis and reduces the risk that the person with
trichomoniasis will become re-infected. Sex should be stopped until the
person with trichomoniasis and all of his or her recent partners
complete treatment for trichomoniasis and have no symptoms.
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Division
of STD Prevention (DSTDP)
CDC
National Prevention Information Network (NPIN)
American
Social Health Association (ASHA)
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Abnormal Vaginal Bleeding
