Mycobacterium leprae--millennium resistant! Leprosy control on the threshold of a new era.

Over the past decades, the conditions of leprosy control implementation have changed dramatically. Introduction of multidrug therapy, together with the global effort of the World Health Organization to eliminate leprosy as a public health problem, had a tremendous impact on leprosy control, particularly by decreasing the registered prevalence of the disease. At the beginning of the new millennium, leprosy control programmes face several new challenges. These relate not only to changes in the prevalence of the disease, but also to changes in the context of leprosy control, such as those created by health sector reforms and other disease control programmes. This review discusses current knowledge on the epidemiology of Mycobacterium leprae and some important aspects of leprosy control. It is argued that our understanding is still insufficient and that, so far, no consistent evidence exists that the transmission of leprosy has been substantially reduced. Sustainable leprosy control, rather than elimination, should be our goal for the foreseeable future, which also includes care for patients on treatment and for those released from treatment. This, however, requires new strategies.