(CNN) - Around the world, health experts are reporting a problem with drug-resistant bacteria.
The antibiotics that once worked are now increasingly ineffective in many cases.
Now global authorities say that one particular sexually-transmitted disease, gonorrhea, has become almost impossible to cure in some cases.
The World Health Organization collected data from 77 countries and found that gonorrhea is showing widespread resistance to drugs that once cleared the infection.
In some countries, it has become "untreatable by all known antibiotics."
Gonorrhea symptoms include a burning sensation when urinating and unusual discharge.
An untreated infection can cause serious health problems, including long-term abdominal pain and pelvic inflammatory disease.
Nearly 80 million people around the world have the STD, and there are 820,000 new cases in the United States every year.
Health experts say gonorrhea is one of 11 types of bacteria that pose a serious threat to human health, specifically because of the urgent need for new antibiotics.
The WHO also called for the development of a vaccine to prevent gonorrhea, and tests for accurately predicting whether an antibiotic will work on a specific infection.
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