An increasing number of young black gay Americans are becoming at risk from gonorrhoea, according to the San Francisco Department of Public Health.

The Department published startling statistics which claimed there has been a 100 per cent increase in the sexually transmitted disease amongst teenagers in the gay black community since 2004.

Health providers have been advised to screen all sexually active black people under 25 and community groups have been set up to fight the trend.

Pennan Barry, a doctor at the Sexually Transmitted Disease and Control Services, said: “We want to make sure that people who are at risk from gonorrhoea are tested and that people who test positive and their partners are treated promptly.

“Once a disease is in a group, it tends to stay there in that group. If we can reduce the amount of gonorrhoea that’s in the general population, then everybody’s risk goes down.”

Gonorrhoea is a bacterial infection which increases the risk of acquiring HIV amongst men and reduces fertility in women.

It is sexually transmitted and easily treatable.