Leprosy and HIV: an analysis

Abstract

After the introduction of HIV in the community, the number of patients with tuberculosis increased. Many of the HIV iníected patients suffer from clinical tuberculosis. Other mycobacterial infections too have an increased incidence among the HIV infected patients, but not so leprosy. Many researchers have looked into this observation, however with conflicting results. But a major increase in leprosy prevalence among HIV infected patients was never encountered, nor a significant increase oí HIV seroprevalence among leprosy patients. In Africa during the past 30 years a continuous fall in the leprosy incidence was seen. However in recent years the decline seems to come to a halt and in some areas an increase is observed. The author speculates that M.leprae does not cause clinical disease in already HIV infected patients, since M.leprae is virtually non-toxic and needs a more or less functioning CMI to cause clinical disease. However the bacterium will multiply, the patient becoming a multibacillary carrier contributing to the infective mycobacterial pool. The non-HIV infected persons then have more chance to be infected and may develop clinical leprosy since they have a functioning CMI. The author thereíore forecast an increase in leprosy incidence over the coming decade in countries, like Brazil, with endemic leprosy, where at present HIV íinds a foothold.