Mary Bowerman

USA TODAY

Antibiotic resistance is causing gonorrhea to become harder and sometimes impossible to treat, according to the World Health Organization (WHO).

Gonorrhea, which is a sexually transmitted disease that can cause infertility if untreated, effects an estimated 78 million people each year, according to WHO. Data from 77 countries, shows the disease has developed resistance to some antibiotics, and an increasing number of countries are finding that the infection can become untreatable by all known antibiotics, according to WHO.

Those numbers might be even higher since lower-income countries where gonorrhea is more common might not have the systems to report untreatable infections, Teodora Wi, medical officer, human reproduction, at WHO, said in a statement.

"The bacteria that cause gonorrhea are particularly smart. Every time we use a new class of antibiotics to treat the infection, the bacteria evolve to resist them," Wi said in a statement.

Gonorrhea can be transmitted through oral, anal and vaginal sex, and can be passed onto a baby during vaginal delivery. The infection can cause pelvic inflammatory disease and infertility if it goes untreated.

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According to WHO, a cocktail of factors have lead to an increase in the disease, including decreased condom use, urbanization and travel, failed treatment and poor infection detection rates.

WHO said that from 2009 to 2014, countries reported resistance to drugs like ciprofloxacin, azithromycin and the current "last resort" treatment of extended-spectrum cephalosporins (ESCs).

In most countries, ESCs are the only antibiotic still effective in treating the disease, according to WHO, which updated its treatment recommendations in 2016 to advise doctors to give two antibiotics for gonorrhea treatment: ceftriaxone and azithromycin.

The medical community desperately needs new antibiotics to treat gonorrhea and longer-term a vaccine to prevent it, according to WHO.

While symptoms of gonorrhea include pain during urination and discharge, often people have no symptoms, according to WHO. The organization notes that doctors sometimes overprescribe antibiotics, which can exacerbate the problem.

“To control gonorrhea, we need new tools and systems for better prevention, treatment, earlier diagnosis, and more complete tracking and reporting of new infections, antibiotic use, resistance and treatment failures,” Marc Sprenger, director of Antimicrobial Resistance at WHO, said in a statement.