STD Awareness: Trichomoniasis, the Pear-Shaped, Blood-Sucking, Silent Scourge

What’s shaped like a pear, hangs with a posse of bacteria, and is a silent scourge upon millions of urogenital tracts? I hope you guessed Trichomonas vaginalis, the single-celled parasite that causes trichomoniasis, or trich (pronounced “trick”). Trich is the most common curable sexually transmitted disease out there — currently afflicting around 3.7 million Americans and 156 million Earthlings.


These single-celled creatures pack a punch, but the body fights back.


When trich causes symptoms, sufferers might experience vaginal discharge (which sometimes has a bad odor), penile burning or discharge, spotting, and itching or swelling in the genital area. But around 70 percent of infections have no symptoms at all, making it a mostly “silent” disease. Based on the totality of the evidence, the Centers for Disease Control and Prevention (CDC) doesn’t currently recommend routine screening for trich in people without symptoms.

But it’s the subject of some debate. Since both symptoms and screenings are rare, and the disease isn’t reportable, some health experts worry that trich could be doing a lot of damage right under our noses. An infection during pregnancy could increase risk for preterm labor or low birth weight. It can increase risk for both acquiring and transmitting HIV from or to a partner. Women with trich are more likely to acquire an HIV infection when sexually exposed to the virus — in fact, one study estimated that 6.2 percent of all HIV infections among U.S. women could be attributed to trich. It’s also easier to catch HIV from a man with trich than from a man without trich. Continue reading

STD Awareness: Which STDs Are Resistant to Antibiotics?

You’ve probably heard of MRSA, which is pronounced “mersa” and stands for methicillin-resistant Staphylococcus aureus — a strain of bacteria that is resistant to methicillin, as well as pretty much every other antibiotic out there. MRSA is an example of evolution by natural selection — what didn’t kill its ancestors made them stronger, spawning a drug-resistant strain.


There are drug-resistant strains of gonorrhea, trichomoniasis, and syphilis.


Evolution is the force behind life’s diversity. Normally, diversity is a good thing — but when it comes to microbes that cause diseases like gonorrhea, trichomoniasis, and syphilis, these organisms’ ability to evolve new defenses against our antimicrobial drugs isn’t good for us.

STDs have plagued us for millennia, but it wasn’t until the 20th century that we finally developed antibiotics, which gave us a powerful tool against many of our most formidable sexually transmitted foes. Suddenly, scourges like gonorrhea and syphilis could be quickly and easily treated with a dose of penicillin.

Problem solved, right? Nope. Enter evolution by natural selection. Continue reading

STD Awareness: Drug-Resistant Trichomoniasis

Two trophozoites of Trichomonas vaginalis, the causative agent of trichomoniasis. Image from the CDC’s Parasite Image Library.

Trichomonas vaginalis organisms, which cause trichomoniasis. Image: Parasite Image Library, CDC

You’ve probably heard of MRSA, which is a strain of Staphylococcus aureus that evolved resistance to all kinds of antibiotics. You also might have heard of other “superbugs,” like Clostridium difficile, aka “C. diff,” or the emerging strains of bacteria that cause antibiotic-resistant gonorrhea. However, other infectious diseases are slowly evolving drug resistance too, but they’re not grabbing headlines. One such disease is trichomoniasis.


We are only starting to learn about drug-resistant trich — and what it means for those who have it.


Trichomonas vaginalis is the single-celled parasite that causes trichomoniasis, or trich (pronounced “trick”). Symptoms can include vaginal discharge (which might have a bad odor), penile burning or discharge, spotting, and itching or swelling in the genital area — but around 70 percent of trich infections are asymptomatic.

Despite its appearance on our list of 10 STDs you’ve probably never heard of, trich is actually the most common curable sexually transmitted disease out there — around 3.7 million Americans are currently infected with trich. When you consider that trich rarely has symptoms, its ubiquity might not even seem all that surprising — there are millions of infections, right under our noses, but mostly unknown and not being aggressively screened for. STD testing doesn’t always include screening for trich, especially in males, who usually don’t have symptoms and can transmit it to others unknowingly. This might not be so bad if trich didn’t cause complications with pregnancy or make it easier to be infected with HIV. Continue reading