Leprosy

​Leprosy is a curable chronic infectious disease caused by the bacillus Mycobacterium leprae. This organism multiplies very slowly and mainly affects the skin, nerves, and mucous membranes (respiratory mucosa and eyes). Leprosy can affect all ages and both sexes. 


Patients are classified as having paucibacillary or multibacillary Hansen’s disease. Paucibacillary Hansen’s disease is milder and characterised by one or more hypopigmented skin macules.

Multibacillary Hansen's disease is associated with symmetric skin lesions, nodules, plaques, thickened dermis, and frequent involvement of the nasal mucosa resulting in nasal congestion and epistaxis.

Throughout history, sufferers have been shunned and often forcibly ostracised by their communities. Leprosy is still a highly stigmatising disease, yet despite its reputation it is not highly infectious.


Transmission
Although the mode of transmission of Hansen's disease remains uncertain, most investigators think that M. leprae is usually spread from person to person in respiratory droplets.

For transmission to occur it usually requires prolonged close contact with an untreated person suffering from an infectious form of leprosy combined with an inherent immunological susceptibility to the disease in the exposed individual. Only 10% of patients with leprosy are infectious if left untreated.

People most at risk of infection are those living in a country with highly endemic disease and people who are close contacts of patients with untreated, active, predominantly multibacillary disease.


Treatment
Leprosy is treated with antibiotics and people receiving antibiotic treatment or who have completed treatment are considered free of active infection.

Worldwide, 1-2 million persons are permanently disabled as a result of Hansen's disease.