An antibiotic-resistant strain of gonorrhea has popped up in England, Japan, and Canada, worrying health officials in both the United States and abroad that the sexually transmitted infection is the world’s newest “superbug.”

Gonorrhea is one of the world’s most common sexually transmitted diseases.

If untreated, it can cause infertility and sterility, and increase susceptibility to HIV. In rare cases, it can even spread to the blood and lead to sepsis.

According to the U.S. Centers for Disease Control and Prevention (CDC), the United States hasn’t seen any cases of this particular antibiotic-resistant strain.

But that doesn’t mean it’s not headed our way. Strains of gonorrhea have traveled quickly across continents in the past.

“Preventing the spread of a new strain of Neisseria gonorrhoeae is very challenging, especially with the ease of international travel,” Dr. Heidi Bauer, chief of the STD Control Branch for the California Department of Public Health, told Healthline via email. “Historically, gonorrhea resistance has traveled from west to east in the United States, starting in Hawaii and on the West Coast and then spreading across the rest of the United States.”

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Adapting Quickly

N. gonorrhoeae is a sly bacterium.

It’s outsmarted many of the treatments aimed at its cure, including the practice of slamming a book down on the penis. The painful ritual was one theory of how the infection got its nickname, “the clap.”

With the advent of antibiotics, gonorrhea was, for a short time, viewed as a pesky “price to pay for sexual freedom.”

But then it did what organisms have done since the beginning of time — it adapted.

When sulfa drugs stopped working, the clinicians of the 1940s quickly chose a new drug, penicillin, to treat the disease.

But mutations in the genetic makeup of the bacteria allowed it to break down penicillin and render it ineffective as a treatment — the first indication that it was capable of becoming resistant to multiple types of antibiotics.

Gonorrhea continues to mutate, and it’s doing so quickly.

Since 1983, scientists have isolated strains of the bacterium resistant not only to penicillin but also to tetracycline, spectinomycin, and fluoroquinolones.

By 2002, just one class of antibiotics, known as cephalosporins, was left to treat the infection. Treatment options included either an oral medication or an intramuscular shot.

But by 2007, it was clear that some of the oral treatments were failing. In 2010, the CDC recommended ceftriaxone, a cephalosporin, given intramuscularly, accompanied by oral azithromycin as the only treatment “to address the potential emergence of gonococcal cephalosporin resistance.”

In short, N. gonorrhoeae has developed resistance to every antibiotic that has been thrown at it. The most recent strain of ceftriaxone resistance is alarming not only because the only treatment we have may be less effective, but also because older strains could stage a comeback.

“If the antibiotic pressure on gonorrhea shifts, then it would not be unexpected to start seeing different antibiotic susceptibility patterns in gonorrhea surveillance,” Bauer said.

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Not-So-Safe Sex

N. gonorrhoeae is a bacterium spread via sexual fluid exchange.

While the use of condoms can prevent its spread to the anus or vagina, reservoirs of the bacteria are often found in the back of the throat, or pharynx — the result of oral sex, which is often viewed as a safer alternative to unprotected vaginal or anal sex.

One of the treatments most useful against the current strain of ceftriaxone-resistant N. gonorrhoeae is spectinomycin, an antibiotic currently unavailable in the United States that has limited efficacy against pharyngeal infections.

Bauer acknowledged the possibility that we may be running out of antibiotics to treat gonorrhea.

“That is the concern and why efforts are needed to prevent the spread of resistant gonorrhea,” she said. “Development of new antibiotics is an important component of preparation for antibiotic-resistant gonorrhea.”

Public health departments like Bauer’s receive notification from clinicians every time a patient is diagnosed with a gonorrhea infection. It’s the second most common “reportable disease” after chlamydia.

So is gonorrhea a superbug?

While Bauer says the California Department of Health “has no basis to comment on the adequacy of the popular use of the term,” she does say, “gonorrhea is an organism that has proven ability to develop resistance to antibiotics. With the sheer magnitude of cases and ease of transmission, the development of multidrug-resistant gonorrhea would create significant burden on the healthcare system and an increase in the health complications of gonorrhea infections.” 

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Hunting the Hidden Bug

There are two tests clinicians use to diagnose the gonorrhea — a quick, inexpensive DNA test or a more complex culture that determines which antibiotics the specific strain of infection is susceptible to.

Usually, clinicians use the DNA test, opting for the culture only if the initial treatment fails. Health departments report the results of cultures to the CDC’s Gonococcal Isolate Surveillance Project (GISP), which tracks the resistant strains of the bacteria and makes decisions about treatment recommendations based on the percentage of treatment failures.

“Clinicians should counsel their patients to return for evaluation if their symptoms persist, at which point clinicians should evaluate for treatment failure by repeating the test and specifically obtaining a culture and antibiotic susceptibility testing,” Bauer advises.

But that current process leaves a glaring gap if those who have antibiotic-resistant gonorrhea don’t return to the clinic if the treatment fails. Gonorrhea is often asymptomatic. Sometimes individuals who practice unsafe sex come in to get tested for STIs, get a DNA test that comes out positive for gonorrhea, get the shot, take the pill, and are none the wiser that the treatment they received is ineffective.

These individuals are not only at risk of long-term complications from the infection such as infertility, but they are ostensibly unknowing carriers of the resistant strains. Additionally, the CDC recommends that all recent sexual partners of the patient be treated, but that’s not always possible.

The potential for the spread of the new, resistant strain of gonorrhea to the United States is highly likely. While those who track the disease are watching carefully, not every clinician knows that there’s a new strain to watch out for.

Somewhere in the United States a healthy, sexually active individual may have already walked into a clinic or urgent care center, where the healthcare provider gave the patient the recommended ceftriaxone shot and oral azithromycin dose. And then, the otherwise healthy patient walked right out.