Talk to patients about trichomoniasis risks

Trichomoniasis, or “trich,” is the most common curable sexually transmitted infection (STI) in the United States, yet only one in five women are familiar with it, according to a new survey commissioned by the American Sexual Health Association (ASHA) in Research Triangle Park, NC.

According to survey results, many women perceive trichomoniasis as the least common STI, when in reality there are more new cases of trich annually in the United States than syphilis, chlamydia, and gonorrhea combined.

“Despite the high prevalence, trich is very much the forgotten STD. The majority of cases don’t have symptoms, and when symptoms do occur, they can be confused with other common vaginal infections,” notes Lynn Barclay, association president and chief executive officer. Other factors come into play, notes Barclay. Trichomoniasis is not a reportable disease. Also, social and economic factors weigh in, with the greatest disease burden found among African American women, she notes.

Women might not be as concerned about trichomoniasis as they are other STIs such as chlamydia, gonorrhea, and HIV because the infection does not have as many adverse health sequelae and there is no routine screening test for it, according to Anita Nelson, MD, professor in the Obstetrics and Gynecology Department at the David Geffen School of Medicine at the University of California in Los Angeles.

Trichomoniasis is caused by a protozoan parasite, Trichomonas vaginalis, that is passed from an infected person to an uninfected person during sex. About 70% of those who are infected display no symptoms. Symptoms in females with the infection include itching, burning, redness or soreness of the genitals, discomfort with urination, or a thin discharge with an unusual smell that can be clear, white, yellowish, or greenish. Men with trichomoniasis might feel itching or irritation inside the penis, burning after urination or ejaculation, or some penile discharge.

The Centers for Disease Control and Prevention (CDC) recommends that any sexually active woman seeking treatment for vaginal discharge be tested for trichomoniasis. However, 65% of women participating in the recent survey said they would not seek medical attention if they experienced symptoms. The women indicated they would wait to see if the symptoms would go away or treat themselves with over-the-counter medicine, which are ineffective against such infection.

What are the possible complications with trichomoniasis infection? Pregnant women who are infected are more likely to have preterm or low birth weight babies. Trichomoniasis also increases the risk of acquiring and transmitting HIV, the virus that causes AIDS. Among women surveyed who were concerned about contracting an STI, nearly half (49%) said they worried about trich increasing their risk of HIV.

Boost partner testing

While testing your patients is important, it also is important to emphasize testing their partners as well, say ASHA officials. One in five people can be reinfected within three months of treatment, according to the CDC.1

Women can be at risk for trich even if they have only one sexual partner, says Barclay. Because the infection is symptomless and can last for many months without treatment, a person can be infected before meeting his or her current partner, she notes. According to the ASHA survey, 63% of women cite having only one sex partner as a reason they would not get tested for infection.

By offering women testing at their routine visits, clinicians could increase awareness of this STI, says Jane Schwebke, professor of medicine in the Infectious Disease Division at the University of Alabama at Birmingham and medical director for the Jefferson County Department of Health’s STD clinic.

Clinicians commonly use wet mount microscopy to test for trichomoniasis due to its wide availability, low cost, and rapid results; however, it is one of the least sensitive Trichomonas vaginalis tests available.2 Culture is considered the gold standard for detecting the Trichomonas parasite, but it can be costly, time-consuming, and only moderately sensitive.3

Two point-of-care tests approved by the Food and Drug Administration — Affirm VPIII (Becton Dickinson, Sparks, MD) and OSOM Trichomonas Rapid Test (Sekisui Diagnostics, Lexington, MA) — are more sensitive than wet mount microscopy, but use is limited to vaginal specimens from symptomatic patients.2

The only federally approved nucleic acid amplification test for trichomoniasis is the APTIMA TV assay (Gen-Probe, San Diego). (Contraceptive Technology Update reported on the approval in its STI Quarterly supplement; see Test now for trichomonas infection; new data shows spread of disease,” September 2011, supplement p. 1.) The amplified nucleic acid assay may be used to test clinician-collected endocervical or vaginal swabs, urine, and specimens collected in PreservCyt solution from symptomatic or asymptomatic women. Trichomoniasis can be cured with a single dose of a prescription antibiotic medication, either metronidazole or tinidazole, both of which can be taken by mouth.

To raise awareness, Barclay says getting the word out to women about trichomoniasis is key, including information about how common it is, how one gets it, when to be tested, and the ease with which it is cured.

“We also can do a better job educating healthcare providers, so they are testing for trich in women with vaginal symptoms and counseling their patients about trich and other STIs,” Barclay says.


1. Centers for Disease Control and Prevention. Trichomoniasis. Accessed at

2. Chapin K, Andrea S. APTIMA Trichomonas vaginalis, a transcription-mediated amplification assay for detection of Trichomonas vaginalis in urogenital specimens. Expert Rev Mol Diagn 2011; 11(7):679-688.

3. Ginocchio CC, Chapin K, Smith JS, et al. Prevalence of Trichomonas vaginalis and coinfection with Chlamydia trachomatis and Neisseria gonorrhoeae in the United States as determined by the Aptima Trichomonas vaginalis nucleic acid amplification assay. J Clin Microbiol 2012; 50(8):2,601-2,608.