A man in the United Kingdom has caught the world's "worst-ever" case of super-gonorrhoea after a sexual encounter with a woman in south-east Asia.

Dr Gwenda Hughes, from Public Health England said this is the first time a case has displayed such high-level resistance to main antibiotic treatment.

The World Health Organization and the European Centres for Disease Control agree this is a world first and  fear the superbug could eventually become untreatable by any antibiotic.