Women may have a greenish yellow, frothy, fishy-smelling vaginal discharge with irritation and soreness in the genital area.
Men usually have no symptoms, but a few have a frothy discharge from the penis and mild pain or discomfort during urination.
Examination of a sample of the discharge under a microscope usually enables doctors to identify trichomoniasis.
Infected people and their sex partners are treated with antibiotics.
Using condoms during genital sex can help prevent passing trichomoniasis and other sexually transmitted infections (STIs) from one person to another.
(See also Overview of Sexually Transmitted Infections Overview of Sexually Transmitted Infections (STIs) Sexually transmitted infection (STI) refers to an infection that is passed through blood, semen, vaginal fluids, or other body fluids during oral, anal, or genital sex with an infected partner... read more .)
Trichomonas vaginalis commonly causes an STI of the vagina in women and an STI of the urinary tract in men and women. Women are much more likely to develop symptoms. About 20% of women develop trichomoniasis of the vagina (trichomonas vaginitis Trichomonal Vaginitis Trichomonal vaginitis is a vaginal infection caused by the protozoa Trichomonas vaginalis. Trichomonal vaginitis is usually sexually transmitted. It can cause a green or yellow discharge... read more ) during their reproductive years.
People with trichomoniasis may also have gonorrhea Gonorrhea Gonorrhea is a sexually transmitted infection caused by the bacteria Neisseria gonorrhoeae, which infect the lining of the urethra, cervix, rectum, or throat, or the membranes that cover... read more or other STIs.
Symptoms of Trichomoniasis
In women, the infection usually starts with a greenish yellow, frothy, fishy-smelling discharge from the vagina. In some women, the discharge is slight. The genital area may be irritated and sore, and sexual intercourse may be painful. In severe cases, the genital area and surrounding skin may be inflamed, and the tissues around the vagina's opening (labia) may be swollen. Urination may be painful or frequent, as occurs in a bladder infection. Urinary and vaginal symptoms may occur alone or together.
Most men with trichomoniasis of the urethra (the tube carries urine from the bladder out of the body) have no or only mild symptoms, but they can still infect their sex partners. Some men have a frothy discharge from the penis, pain during urination, and an urge to urinate frequently.
Did You Know...
Diagnosis of Trichomoniasis
Examination and sometimes culture of a sample of the discharge or urine
Doctors suspect trichomoniasis in the following people:
Women with vaginal infections Overview of Vaginitis (Vaginal Infection or Inflammation) Vaginal infections are one of the most common reasons women see their doctor, accounting for millions of visits each year. Vaginal infections are caused by infectious organisms (such as bacteria... read more as well as their sex partners
The organism is much more difficult to detect in men than in women.
In women, the diagnosis can usually be made quickly by examining a sample of the vaginal discharge with a microscope and identifying the organism. If results are unclear, the sample is cultured for several days.
In men, a sample of the discharge from the end of the penis (obtained in the morning, before urination) may be examined under a microscope and sent to the laboratory for culture. Alternatively, doctors sometimes do tests to identify the organism’s unique genetic material (DNA or RNA) using techniques that increase the amount of the bacteria's genetic material. These tests are called nucleic acid amplification tests (NAATS). These techniques make the organisms easier to detect.
Occasionally, microscopic examination of the urine detects Trichomonas, but identification is more likely if a urine culture is done.
Tests for other STIs are usually also done because people with trichomoniasis may also have gonorrhea Gonorrhea Gonorrhea is a sexually transmitted infection caused by the bacteria Neisseria gonorrhoeae, which infect the lining of the urethra, cervix, rectum, or throat, or the membranes that cover... read more or a chlamydia Chlamydia and Other Nongonococcal Infections Chlamydial infections include sexually transmitted infections of the urethra, cervix, and rectum that are caused by the bacteria Chlamydia trachomatis. These bacteria can also infect... read more .
Treatment of Trichomoniasis
The antibiotic metronidazole or tinidazole
Simultaneous treatment of sex partners
Women are usually treated with a seven-day course of antibiotics, either metronidazole or tinidazole. Men may be treated with a single dose. Their sex partners must be treated simultaneously or women may be reinfected. Sometimes, if a woman's partner is unlikely to return for follow-up, the woman is given medications or a prescription to deliver to her sex partner (called expedited partner therapy Sex partners ).
Metronidazole may cause a metallic taste in the mouth, nausea, or a decrease in the number of white blood cells. Women who take the medication may be more susceptible to vaginal yeast infections Vaginal Yeast Infection (Candidiasis) A vaginal yeast infection (also called candidiasis) is caused by an infectious organism called Candida, usually Candida albicans. A vaginal yeast infection may cause intense itching... read more (vaginal candidiasis).
Infected people should abstain from sexual intercourse until the infection is cured, or they can infect their partners.
Prevention of Trichomoniasis
The following general measures can help prevent trichomoniasis (and other STIs):
Safer sex practices, including using a condom Condoms Barrier contraceptives physically block the sperm’s access to a woman’s uterus. They include condoms, diaphragms, cervical caps, contraceptive gels, contraceptive sponges, and spermicides (foams... read more every time for oral, anal, or genital sex
Decreased risk of exposure to STIs by reducing the number of sex partners, not having high-risk sex partners (people with many sex partners or who do not practice safer sex), or practicing mutual monogamy or abstinence
Prompt diagnosis and treatment of the infection (to prevent spread to other people)
Identification of the sexual contacts of infected people, followed by counseling or treatment of these contacts