With the advent of so-called drug "cocktails" to treat HIV infections, doctors say that the number of cases of other sexually transmitted diseases have escalated in Spain over that past 10 years because more people are having unprotected sex.
Between January and November 2010, physicians at the Carlos III Health Institute report that there were 2,927 new cases of syphilis and 2,148 new infections of gonorrhea - double and triple figures respectively over the same time period 10 years prior.
At the Sandoval Health Center in Madrid, which specializes in treating STDs, officials say that the number of cases of papilloma - the virus that causes cervical and anal cancer - gonococcal infections, trichomoniasis and chlamydia have also increased. New HIV infections are also on the rise.
It was at the Sandoval center that researchers - along with those at the Ramón y Cajal hospital - found that there was an increase of lymphogranuloma venereum, a disease that infects the lymph nodes and hadn't been reported in the West until 2008.
In Madrid alone, there have been more than 100 cases since 2009, with 54 in 2011. Last year, 72 cases of lymphogranuloma venereum were reported in Barcelona.
Jorge del Rivero, of the Sandoval Center, says similar rises are also cropping up in London, Paris and Milan.
If left untreated, the disease can cause genital and anal deformations. Experts say that lymphogranuloma venereum is more frequent in homosexual or bisexual men but increasing numbers of women in Madrid are seeking treatment for the disease.
According to the World Health Organization some 450 new cases of syphilis, gonococci. chlamydia and trichomoniasis are reported each year. And according to the UNAIDS, there are some 2.7 million new HIV cases reported annually.