epidemiology

Last reviewed 01/2018

Mycobacterium leprae affects 12 million people in the tropics and the subtropics. About 66% are in Asia.

Once infected, the subsequent progression to clinical disease is dependent on various factors:

  • sex - males appear to be more susceptible than females. A ratio of about 2:1 is seen in India.

  • genetics - there has been shown to be a concordance with respect to susceptibility in identical but not non-identical twins

  • the patient's immune response - a patient with an ineffective immune response is likely to develop the lepromatous form of the disease, rather than the tuberculoid form seen in patients with an effective immune response