Gonorrhea strains circulating in China are increasingly showing signs of emerging resistance to the only two World Health Organization (WHO)–recommended antibiotics for treating the common sexually transmitted infection (STI).

A new scientific paper identifying this trend joins numerous researchers and health officials around the world, including in the United States, in warning that untreatable gonorrhea may soon start to spread.

New antibiotics are in development; however, two pressing questions hang over such research: Will these treatments prove safe and effective for the treatment of gonorrhea? And will new antibiotics hit the market in time to ward off any emerging strains of the STI that prove resistant to all available antibiotics?

Throughout the history of antibiotic treatment for gonorrhea, the STI has developed resistance to all such treatments. Currently, the only recommended treatment is a dual therapy with azithromycin and ceftriaxone.

Publishing their findings in PLOS Medicine, researchers analyzed data on 3,849 isolates of gonorrhea taken between 2013 and 2016 from infected individuals living in seven provinces in China.

A total of 18.6 percent of the gonorrhea isolates analyzed in this new study were resistant to azithromycin, and 10.8 percent showed decreased susceptibility to ceftriaxone. (Decreased susceptibility is a sign that a strain of an STI may progress to become resistant to an antibiotic.)

In 2013, 1.9 percent of the gonorrhea isolates were both resistant to azithromycin and had decreased susceptibility to ceftriaxone. By 2016, this figure had increased to 3.3 percent. This increase was statistically significant, meaning it is not likely to have been driven by chance.

Just because an STI is resistant to certain antibiotics does not necessarily mean it is untreatable. Nevertheless, the increasing rate of dual-antibody-resistant gonorrhea has led the study authors to project that azithromycin and ceftriaxone may ultimately prove ineffective against gonorrhea in China.

To read a press release about the study, click here.