The sexually transmitted disease gonorrhoea risks becoming a drug-resistant "superbug" if doctors do not devise new ways of treating it, a leading sexual health expert said.
Catherine Ison, a specialist on gonorrhoea from Britain's Health Protection Agency said a World Health Organisation (WHO) meeting in Manila next week would be vital to efforts to try to stop the bug repeatedly adapting to and overcoming drugs.
"This is a very clever bacteria. If this problem isn't addressed, there is a real possibility that gonorrhoea will become a very difficult infection to treat," she said in a telephone interview.
Gonorrhoea is a common bacterial sexually-transmitted infection and if left untreated can lead to pelvic inflammatory disease, ectopic pregnancy and infertility in women.
Globally, the WHO estimates that there are at least 340 million new cases of curable sexually transmitted infections -- including syphilis, gonorrhoea, chlamydia and trichomoniasis -- every year among people aged 15 to 49.
Ison said the highest incidences of gonorrhoea were in south and southeast Asia and sub-Saharan Africa, but as yet the WHO has no breakdown by individual infection type.
Current treatment for gonorrhoea in most countries consists of a single antibiotic dose of either cefixime or ceftriaxone.
But Ison, who is due to speak on the issue at a Society for General Microbiology conference in Edinburgh on Tuesday, said strains of the Neisseria gonorrhoeae bacteria were starting to become resistant and could soon become impervious to all current antibiotic treatment options.
"Ceftriaxone and cefixime are still very effective but there are signs that resistance, particularly to cefixime is emerging and soon these drugs may not be a good choice," she said.
Instances of gonorrhoea being resistant to multiple drugs -- the definition of a "superbug" -- have started to appear in Japan, where health authorities had decided to up the dose to treat the disease, but stick with the same antibiotic, she said.
Other reports of rising gonorrhoea drug resistance had also come from Hong Kong, China, Australia and parts of Asia.
Ison said the best way to try to reduce the risk now -- beyond encouraging the use of condoms which halt the spread of sexually transmitted diseases -- would be to treat gonorrhoea with two different antibiotics at the same time.
This is a technique used in the treatment of some other diseases like tuberculosis and one that makes it more difficult for the bacteria to learn how to conquer the drugs.
"There are few new drugs available. So using more than one at the same time is probably what should happen in the first instance," said Ison. "We also need to set up good lines of communication between countries so that we can all talk to each other about what's happening in gonorrhoea and make sure we change treatment strategies when we need to."
A WHO spokeswoman said its experts would discuss drug-resistant gonorrhoea at a meeting in the Philippine capital Manila next week.