Guangdong is known for its raunchy nightlife, KTV parlors and saunas, and now it looks like venues like these – some which provide sexual services – could be behind a sharp increase in the number of sexually transmitted diseases diagnosed in the province.

There are now 158,192 people in the province with an STD. The rates for syphilis and gonorrhea in Guangdong actually lead the country, according to figures released by the province’s Dermatosis Prevention and Curing Institute.

There were 10,000 cases of syphilis in Guangdong in 2013, outranking Zhejiang Province with the second highest infection rate. From 2002 to 2013 the province’s number of patients with syphilis and gonorrhea has continued to surpass national average, the report said. And many patients were in labor-intensive areas in the Pearl River Delta, it added, like Dongguan.

What is most interesting is who appears to be most at risk: senior citizens. While most cases are youngsters and middle-aged men, the sharpest increase is among the senior set, partly due to the fact that many lonely seniors tend to seek sexual services in low-end sexual venues often without protection, said Yang Bing, director of a medical institute.

From 2004 to 2013, the province reported more than 4,000 cases of third-phase syphilis with many being male senior citizens, according to Yang.

Photos: Economist