Growing resistance to antibiotics has complicated efforts to rein in common sexually transmitted diseases like gonorrhoea, chlamydia and syphilis, the World Health Organization warned Tuesday as it issued new treatment guidelines.
Globally, more than one million people contract a sexually transmitted disease (STD) or infection (STI) every day, WHO said.
"Chlamydia, gonorrhoea and syphilis are major public health problems worldwide, affecting millions of peoples' quality of life, causing serious illness and sometimes death," Ian Askew, head of WHO's reproductive health and research division, said in a statement.
WHO estimates that each year, 131 million people are infected with chlamydia around the globe, 78 million with gonorrhoea and 5.6 million with syphilis.
More than one million people contract a sexually transmitted infection (STI) every single day, WHO medical officer Teodora Wi said.
Until recently, the three diseases, which are all caused by bacteria, had been fairly easy to treat using antibiotics, but increasingly those drugs are failing, WHO said.
"Resistance of these STIs to the effect of antibiotics has increased rapidly in recent years and has reduced treatment options," the UN agency said.
Resistance is caused, among other things, by doctors overprescribing antibiotics, and patients not taking the correct doses.
Injected into the buttock or thigh
Strains of multidrug resistant gonorrhoea that do not respond to any available antibiotics have already been detected, while antibiotic resistance also exists in chlamydia and syphilis, though it is less common, it said.
When left undiagnosed and untreated, the three diseases can have serious consequences, causing pelvic infamatory disease and ectopic pregnancy in women, and increasing the chances of miscarriage, stillbirth and newborn death.
They can also greatly increase the risk of being infected with HIV, and untreated gonorrhoea and chlamydia can leave both men and women infertile.
To rein in resistance, WHO on Tuesday presented new guidelines aimed at ensuring that doctors prescribe the best antibiotics, and the right doses, for treating each specific disease.
To reduce the spread of the diseases, national health services will need to "monitor the patterns of antibiotic resistance in these infections within their countries," Askew said.
For gonorrhoea for instance, WHO recommends that health authorities study local resistance patterns and advise doctors to prescribe the most effective antibiotic with the least resistance.
For syphilis, meanwhile, WHO recommended a specific antibiotic—benzathine penicillin—that is injected into the buttock or thigh muscle.
It stressed that condom use was the most effective way to protect against STD infection.
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