Every day, more than a million people around the world get a sexually transmitted infection, the World Health Organization said last week. It added that rates of chlamydia, gonorrhea, trichomoniasis and syphilis are especially worrying.

　　The majority of the infections are easily preventable and curable. But in a new report, the WHO said that some diseases - especially gonorrhea – are changing over time into so-called super-bug forms. That makes them increasingly difficult to treat with drugs, or antibiotics.

　　"Sexually transmitted infections are everywhere. They are far more common than we think," said Teodora Wi, a medical officer in the WHO's department for reproductive health and research.

　　The WHO's report shows that, among men and women between the ages of 15 and 49, there were 127 million new cases of chlamydia in 2016, 87 million of gonorrhea, 6.3 million of syphilis and 156 million of trichomoniasis.

　　The WHO based its report on 2016 data, the latest available worldwide information.

　　Sexually transmitted infections, or STIs, are a "persistent and endemic health threat worldwide," the WHO said in its report. This means they are ongoing and difficult to stop. The WHO also said that STIs have a great effect on both adult and child health.

　　If STIs are left untreated, they can lead to serious, long-term health effects. These include heart and nervous systems diseases, pregnancy-related problems and an increased risk of HIV. An untreated STI also increases the chance of stillbirths -- babies being born dead.

　　Syphilis alone caused an estimated 200,000 stillbirths and newborn deaths in 2016. In fact, it is one of the leading causes of baby loss worldwide, the research found.

　　Peter Salama is the WHO's director for universal health coverage. He said the data showed the need for "a concerted effort" to make sure everyone, everywhere, can get the services they need to prevent and treat these diseases.

　　Sexual infections caused by bacteria can normally be treated and cured with widely available medicines. But recent shortages in the supply of the drug benzathine penicillin made it more difficult to control syphilis, the WHO study said. Rising drug resistance to gonorrhea treatments is another growing health threat.

　　Tim Jinks is an infectious disease specialist at Britain's Wellcome Trust global health charity. He told the Reuters news agency that the increase in cases of STIs was alarming, especially because some antibiotics appear to be getting less effective.

　　"The high numbers of cases of gonorrhea are of particular concern," he wrote in an email. "We are increasingly seeing incidences of so-called ‘super-gonorrhea' which are practically impossible to treat."

　　The study and data appear online in the Bulletin of the World Health Organization.

　　I'm Anne Ball.

　　Kate Kelland of Reuters news agency reported this story. Anne Ball adapted the story for VOA Learning English. Ashley Thompson was the editor.

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