"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," said Teodora Wi, a human reproduction specialist at the WHO, in a news release.
Three superbugs -- bacteria that cannot be killed by the best available drug -- were detected in Japan, France and Spain, according to the WHO.
"We need to be more vigilant now," Wi told reporters in a phone briefing.
