Here’s a word you probably haven’t thought about since high school health class: gonorrhea.

We’re not bringing it up to test your spelling prowess. No, we’ve got some news that might scare the pants off (and hopefully a condom on) you: Scientists have discovered a cluster of gonorrhea infections that are building a resistance to common antibiotics, the Centers for Disease Control and Prevention announced this week.

“If resistance continues to increase and spread, current treatment will ultimately fail and 800,000 Americans a year will be at risk for untreatable gonorrhea,” said Jonathan Mermin, M.D., director of CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.

So, yeah, not to be alarmist, but this could be a problem.

Quick primer: For men, gonorrhea symptoms include a burning sensation while urinating, a white, yellow, or green discharge, and (less commonly), painful, swollen testicles, per the CDC. Gonorrhea can be spread by having vaginal, anal, or oral sex with someone who’s infected. And it’s the second most commonly reported infectious disease in the U.S., the CDC says. Around 820,000 Americans contract new infections each year, but more than half of those cases go detected.

The recommended treatment to cure gonorrhea is an antimicrobial one-two punch of a single shot of 250mg ceftriaxone and 1g of oral azithromycin. The use of two antibiotics improves the success of treatment and serves to slow the infection’s resistance to medication (or at least that’s what scientists have hoped). But it can’t reverse any permanent damage, like infertility, done by the disease.

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These two drugs are the last viable, effective treatments for gonorrhea available for men and women. However, for years, there’s been concern their efficacy is faltering. And the epicenter of that new outbreak is, unfortunately, Honolulu.

Scientists from the CDC and Hawaii’s Department of Health reported seven cases in which Neisseria gonorrhoeae bacteria showed high-level resistance to azithromycin and reduced susceptibility to ceftriaxone in Honolulu in April and May 2016, according to a press release. Fortunately, while the bacteria was far more resistant to azithromycin than normal, the six men and woman were all treated successfully using the dual regimen, and there’s been no confirmed failures of the CDC-recommended dual treatment in the U.S.

Regardless, it’s still troubling. So just in case, the CDC says they’re testing an experimental oral antibiotic as a possible new way to treat treatment of gonorrhea. Called ETX0914, the new antibiotic is a single-dose oral drug that can be used as an alternative to ceftriaxone injection as part of the recommended therapy for gonorrhea. In the study, researchers treated 179 gonorrhea participants (167 men, 12 women) using ETX0914 alone (at either 2g or 3g dosage levels) or ceftriaxone alone. All of the patients in the 3g ETX0914 dose group and all but one of the patients in the 2g dose group were cured. A handful of patients (21/179) reported mild side effects, but most were primarily gastrointestinal.

But hey: Why risk the odds in the meantime? Wear a condom to reduce your risk of contracting an STI. (There’s even a new condom that’s mind-meltingly thin and practically unbreakable, called Hex. Try it out if you’re hell-bent against rubbers.)

It’s a smart move—mutant gonorrhea or not.

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