Objectives: An epidemic situation on human immunodeficiency virus infection can be stopped and even compelled to step back, if adequate and comprehensive prophylactic measures are performed in the proper time.Methods: Prophylactic measures should be, directed on those groups, who are at high risk for becoming infected or who are carriers of HIV as the top priority. The epidemic situation in HIV infection in the northwestern region of Russia has been analyzed. The ways of the spread of HIV infection among the infected persons, residents of the St. Petersburg region, Kaliningrad, Novgorod, and Murmansk, have been studied. The infection is transmitted mainly through sexual contacts, both homosexual and heterosexual. High migration activity of HIV-infected persons, homo- and heterosexuals, has been established and a great number of unknown (casual) sexual contacts among them noted.Results: The results of these observations may be useful in the prognostication of the epidemic situation in HIV infection not only in the northwestern region, but also beyond its boundaries, and later in the optimization of screening.Conclusions: The pandemic of HIV infection causes enormous economic damage, destabilizes the socio-political situation in many countries of the world, and hinders the achievement of aims for the development of millennium, both in the area of health protection and in other spheres. In Novgorod region an epidemic situation on HIV infection is estimated as one of most strained one. The basic indexes and tempos of their growth in a region are higher in relation to average federal data. But it can be stopped and even compelled to step back. © 2015, The Japanese Society for Hygiene.