Trichomoniasis Is the Overlooked STI Behind a "Hot Debate" in Sexual Health

"You have all these problems associated with it."

Some STIs are definitely more famous than others. HPV is often described as the most common STI, there’s a British Netflix series about chlamydia, and, with the rise of superbugs, gonorrhea is starting to look even more concerning. Compared to those STIs, a disease called trichomoniasis has lurked in the background. Two sexual health experts, however, believe the world needs to know about it.

Trichomoniasis is actually caused by a protozoan parasite called Trichomonas vaginalis, which can infect the lower genital tract — usually the vagina, cervix, or urethra. This parasite primarily dwells in fluids that are exchanged during sex (like semen or vaginal fluid) though occasionally, it can be passed on sex toys if fluid lingers.

The parasite more commonly affects women, but trichomoniasis can be acquired by both women and men. The CDC estimates that trichomoniasis only produces symptoms in 30 percent of people — so most people won’t actually show any symptoms of their infection.

trichomoniasis
Trichomoniasis is caused by a protozoan parasite that travels through fluids exchanged during sex.

But for those who do show symptoms, Christina Muzny, Ph.D., an infectious disease specialist at the University of Alabama, explains that there’s no single symptom that is a tell-tale sign of trichomoniasis. Some patients, mostly women, will experience a “frothy” vaginal discharge or sometimes a strange odor, but those factors are also common symptoms of other conditions like yeast infections or bacterial vaginosis. The only way to truly confirm a case of trichomoniasis, Muzny says, is to get tested for it. Still, she tells Inverse that trichomoniasis isn’t really on most people’s radars.

“It’s kind of a hot debate in my field.” Muzny says. “A lot of people around the country are not routinely screening for it, which I think is a problem.”

How Common Is Trichomoniasis?

Trichomoniasis isn’t reportable to the CDC, which means the federal public health authority doesn’t keep data on how prevalent it is. However, Charlotte Gaydos, Ph.D., a professor of medicine at Johns Hopkins University, estimates that it’s far more common that most people believe.

“We know that it is very prevalent, Gaydos tells Inverse. “It’s more common than gonorrhea and chlamydia put together. Estimates are that it’s 3.7 million cases [per year] in the United States, but I say estimated because it’s not reportable. No one reports trichomoniasis, so we don’t have good data.”

Gaydos’ has collected data, though, and her work suggests that trichomoniasis tends to be more prevalent in black communities. In her 2018 study published in Clinical Infectious Diseases, Gaydos reviewed urine samples from 4,057 individuals and found that trichomoniasis was present in 0.5 percent of women and 1.8 percent of men in the population overall. But it was present in 4.2 percent of black men and 8.9 percent of black women in her sample.

This disparity alone adds some weight to the idea that the CDC should be tracking trichomoniasis more closely. But researchers like Gaydos argue that data is especially important because trichomoniasis has been linked to other, more severe health complications.

Not a “Nuisance” Organism

Gaydos says that many people consider trichomoniasis a “nuisance” organism. This is, in part, because it lacks the same startling symptoms found in some other STIs. But trichomoniasis has been linked to other conditions that make it unwise to ignore a potential infection.

“Trichomoniasis is know to cause complications with pregnancy, pre-term birth, post-operative gynecological infections. It’s known to increase risk of HIV. It can contribute to infertility in men. You have all these problems associated with it,” Muzny says.

sperm
Trichomoniasis has been linked to declines in sperm motility in men

Overall, Muzny and Gaydos argue that there could be many potential health consequences associated with trichomoniasis that make it deserving of more attention, especially for women, who tend to experience symptoms at higher rates than men. But even for men, Gaydos believes that it’s worth taking a closer look at trichomoniasis.

“There have been research studies that associate it with a significant decrease in sperm motility and viability, which I think is very interesting,” she adds. “It’s perhaps informative that maybe we should be looking harder at what the actual sequelae are.”

Despite these potentially concerning consequences of a Trichomoniasis vaginalis infection, both researchers add that it’s fairly simple to treat. Currently, trichomoniasis is treated with one dose of either metronidazole or tinidazole — though Muzny just finished a clinical trial showing that a 7-day dose of metronidazole tended to help women kick the infection sooner. They both expect to see the treatment guidelines updated in 2020, and they will meet with other experts in the field this summer to make the case that trichomoniasis should be a bigger presence on the CDC’s radar, or at least something that people routinely look to get screened for during health checkups.

“It’s part of the goal of my career to make it reportable,” says Muzny. “We’re working on that too in the updated guidelines.”