Abstract
The epidemiology of AIDS reflects interactions among biological, psychological and social factors. The immune response to the infectious agent is relatively ineffectual; the course of the disease it produces is chronic. The long interval between HIV infection and the appearance of clinical disease maximizes “silent” transmission. The infection is transmitted behaviourally; that is, primarily via specific sexual acts and contaminated paraphernalia employed by IV drug users. The virus entered human populations in an era when such behaviours had become very much more prevalent in response to social change. The public health response to the epidemic was seriously compromised by the stigma attached to the persons victimized by the disease; thus, the mobilization of adequate resources was markedly delayed. Irrational fears of contamination led to proposals for mandatory population-wide screening, in utter disregard of the high false to true positive ratio in screening tests when prevalence is low. Welcome as a vaccine to prevent HIV infection would be, it is not likely to be available, if it can be produced at all, before the end of the century. Control of the epidemic demands that stigma be vigorously combated and that all groups of the population be educated about ways to minimize the likelihood of becoming infected and of transmitting the virus.
