Urban clusters of sexually transmitted diseases in the city of Seville, Spain

Abstract

To test the hypothesis that there is an increased risk for sexually transmitted diseases in certain geographic areas, 613 patients diagnosed as having sexually transmitted diseases in Seville, Spain, were studied in relation to their address. Increased risks of gonorrhea (relative risk, 3.72), syphilis (relative risk, 3.32), Chlamydia trachomatis infections (relative risk, 3.41), and the three conditions together (relative risk, 3.52) were found in district 1, which represents the core of transmission and the central area of old Seville. These findings represent the first description of spatial clusters for syphilis and Chlamydia trachomatis infections.