A city’s reputation as a drug-friendly “party town” is being linked to high rates of sexually transmitted diseases.

According to a report by Brighton and Hove City Council, 31% of people who admitted to using drugs in the last year also reported sexually transmitted infections, giving the city the third highest STI rate outside of London.

The report links this to the city’s “fun-loving, party town” image.

Figures show the number of people infected with gonorrhoea in Brighton and Hove has increased by almost 60% in just two years, lifting the city’s population to three times the national rate of infections.

Sexual health experts said a drop in condom use, improved testing, a high gay male population and under-25s treating the city as a “party town” also lay behind the spike.

The latest figures available from the Health Protection Agency reveal there were 107 diagnoses per 100,000 of the population in 2011 compared to 71 in 2009.

By comparison, there were 39 diagnoses per 100,000 of the population in England as a whole, nine diagnoses for East Sussex and 17 for West Sussex.

And across Sussex, figures from Public Health England (PHE) show a steady increase in the number of HIV cases in 2012, with 235 new diagnoses and 40 deaths related to the disease.

HIV expert Dr Daniel Richardson, from the Lawson Unit at the Royal Sussex County Hospital, said: “There is definitely an increased trend in Brighton that shows a link between recreational drugs, including injecting, and cases of HIV. Every year after the Pride weekend, for instance, we prepare for increased screenings.”

LGBT charity Stonewall said that although recreational drug use was of concern, poverty and poor sex education also needed to be considered and the problem was “certainly not limited to gay people”.