Introduction

Abstract

In the brief span of a decade, the AIDS pandemic has spread to virtually all corners of the world. While data are imprecise at best, especially those related to HIV-1 prevalence, an illumi­nating global picture has nevertheless emerged (Table 1). Of a total world population of approx­imately five billion in 1990, about eight million adults are estimated to be HIV-1-infected, according to the Global Programme on AIDS of the World Health Organization (WHO) (1). Approximately 0.3% of the world’s adults are HIV-1-infected. Between developing and industri­alized countries, the distribution of total population and HIV-1-infected adults is approximately symmetrical. Developing countries, with about 76% of the world’s population, are estimated to contain about 81% of the world’s HIV-1 infections. Industrialized countries, with 24% of the world’s population, contain about 19% of HIV-1-infections