8.28. The AIDS pandemic is a major concern in both developed and developing countries. WHO estimates that the cumulative number of AIDS cases in the world amounted to 2.5 million persons by mid-1993 and that more than 14 million people had been infected with HIV since the pandemic began, a number that is projected to rise to between 30 million and 40 million by the end of the decade, if effective prevention strategies are not pursued. As of mid-1993, about four fifths of all persons ever infected with HIV lived in developing countries where the infection was being transmitted mainly through heterosexual intercourse and the number of new cases was rising most rapidly among women. As a consequence, a growing number of children are becoming orphans, themselves at high risk of illness and death. In many countries, the pandemic is now spreading from urban to rural areas and between rural areas and is affecting economic and agricultural production.