The second part of the review article analyzes the current epidemiological situation with sexually transmitted infections (STIs) and addresses the sexual behavior of patients at risk for STIs. Since the main route of STIs transmission is the sexual route, rectal localization of STIs is more common in people who have anal sex. Therefore, the authors pay special attention to bacterial STIs localized in the perianal area and causing diseases such as syphilis, gonorrhea, venereal lymphogranuloma, chancroid, etc. Syphilis and HIV share a similar epidemiological process as well as routes and modes of transmission, both of which contribute to infection in high-risk groups. Syphilis infection increases the risk of acquiring HIV infection 2-4-fold. Therefore, an increase in infections and the emergence of late-onset neurosyphilis in HIV-infected patients can be predicted in the coming years. Rectal gonorrhea in patients is most often asymptomatic. Nonspecific proctitis is mostly regarded as proctitis of chlamydial etiology. Clinical cases of venereal lymphogranuloma are closely associated with concomitant HIV infection in men who have sex with men. In rectal localization, the infection may be asymptomatic but may initially be accompanied by anal itching and discharge, rectal pain, fever, and tenesmus. Often, rectal manifestations of STIs may not be visible due to difficulty visualizing this localization. The authors note that practitioners are not always alert to the possible presence of a perianal STI (as part of the differential diagnosis or as a factor complicating the course of the underlying disease).