The Little Known STI That Can Have Big Consequences
Research and Innovations Trichomoniasis is one of the most common sexually transmitted infections (STI) in North America and can have serious health consequences, but most people have never heard of it.

The parasitic infection, caused by an organism called Trichomonas vaginalis, is more common than chlamydia and gonorrhea combined. In the U.S., an estimated 3.7 million people have trichomoniasis, according to the Centers for Disease Control and Prevention, but only 30 percent of patients will show signs of infection.
Women with trichomoniasis, also known as “trich,” typically experience vaginal discharge, odour, irritation, and pain during urination or sex — symptoms that can easily be mistaken for other conditions such as yeast infections, bacterial vaginitis, or other STIs.
“This makes it very challenging to make a diagnosis based on clinical symptoms alone,” says Dr. Anu Rebbapragada, director of the microbiology lab at Dynacare, a health solutions company. “That’s why an accurate test is required — a test that is highly specific and highly sensitive, that can distinguish between the different pathogens that can infect a woman, and give a definitive diagnosis.”
Testing for “trich”
Traditionally, to test for trichomoniasis, a medical laboratory would look at a patient’s specimen under a microscope, searching for the live parasitic organisms.
“The problem is that most organisms are dead on arrival by the time the specimen reaches the lab, and in order for microscopy to accurately identify infection with trichomonas, you need at least 1,000 swimming, motile organisms on the slide,” says Dr. Rebbapragada. “So it’s a very poor sensitivity test.”
Studies indicate that traditional methods of testing missed up to 50 percent of trichomoniasis infections.
Due to these shortcomings, starting in August 2014 Dr. Rebbapragada’s lab decided to offer the nucleic acid amplification test (NAAT), a form of molecular testing that detects specific genetic material found only in the Trichomonas vaginalis parasite.
Once diagnosed, trichomoniasis can be cured with a seven-day course of antibiotics. However, if left untreated, it can lead to pelvic inflammatory disease and complications during pregnancy, and can increase the risk for HIV, cervical cancer, and infertility.
Though men can be infected with trichomonas — causing penile discharge, irritation, and some burning after urination or ejaculation — Health Canada has only approved using NAAT for women, and it can be done using a vaginal or cervical swab, or a urine sample.
“It’s highly sensitive for the presence of this organism, and it can detect even one organism in the specimen, whether or not the patient is showing any symptoms” says Dr. Rebbapragada, adding that with this test, trichomoniasis detection has doubled in the lab’s patient population. “This test has uncovered a lot of infections that were going missed before.”
Detection key to diagnosis
Once diagnosed, trichomoniasis can be cured with a seven-day course of antibiotics. However, if left untreated, it can lead to pelvic inflammatory disease and complications during pregnancy, and can increase the risk for HIV, cervical cancer, and infertility.
With NAAT, Dr. Rebbapragada says, medical labs now have the tools necessary to help definitively diagnose trichomoniasis and, it’s hoped, fully avoid these complications.
“Molecular testing is really creating a revolution in how we detect and manage infection,” she says. “We’re not going to be in the dark anymore with STIs.”