More than 1 million people a day get a sexually transmitted infection, WHO says

More than a million people worldwide catch a sexually transmitted infection every day, the World Health Organization (WHO) said on Thursday.

Four infections — chlamydia, gonorrhea, trichomoniasis and syphilis — account for a combined total of more than 376 million new cases annually, the WHO said in a report.

The vast majority of the infections are easily preventable and curable, the organization said, but some diseases, especially gonorrhea, are evolving into superbug forms that are increasingly difficult to treat with 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 report, based on 2016 global data — the most recent available — showed 127 million new cases of chlamydia that year, along with 87 million cases of gonorrhea, six million cases of syphilis and 156 million cases of trichomoniasis among men and women aged 15 to 49.

Sexually transmitted infections, or STIs, are a "persistent and endemic health threat worldwide" and have a profound impact on both adult and child health, the WHO said.

If left untreated, they can lead to serious and chronic health effects that include neurological and cardiovascular disease, infertility, ectopic pregnancy, stillbirths and an increased risk of HIV.

Syphilis alone caused an estimated 200,000 stillbirths and newborn deaths in 2016, making it one of the leading causes of baby loss globally, the research said.

Rates of infection haven't declined since 2012, the World Health Organization said. 

"We're seeing a concerning lack of progress in stopping the spread of sexually transmitted infections," said Dr. Peter Salama, WHO's executive director for universal health coverage, in a news statement. 

"This is a wake-up call for a concerted effort to ensure everyone, everywhere can access the services they need to prevent and treat these debilitating diseases."

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

Tim Jinks, a specialist in infectious disease at Britain's Wellcome Trust global health charity, said the increase in cases of STIs was alarming, especially given that some antibiotics are becoming less effective due to drug resistance.

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

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