Until 1995 central and eastern Europe as well as the Asian republics of the former Soviet Union have been more-or-less devoid of epidemic outbreaks of HIV infection. In this region with more than 450 million inhabitants (United Nations 1997), the total number of HIV infections was estimated lower than 30.000 (WHO 1995; UNAIDS 1996). Most of these infections resulted from sexual and nosocomial transmission. In 1995 this epidemiologically soporific picture started changing drastically in two ways. Firstly, reports on rapid HIV outbreaks in various parts of the former Soviet Union started to surface, and, secondly, these new infections were almost exclusively associated with another major public health crisis that until then had gone largely unnoticed: the rapid diffusion of drug injecting. Indeed, the social networks of drug injectors have provided an almost custom-tailored infrastructure for the virus to spread through the former Soviet Union and most HIV cases are reportedly related to illicit drug injecting. Except for Poland and Yugoslavia, the countries in central and southeast Europe have not yet experienced epidemic HIV spread, although in many of these countries drug injecting has become a major public health concern as well
