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
Last reviewed 01/2018