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Leprosy is a chronic disease caused by a bacillus, Mycobacterium leprae, an acid-fast, rod-shaped bacillus. Leprosy mainly affects the skin, the peripheral nerves, mucosa of the upper respiratory tract and the eyes, apart from some other structures. Depending on the bacillary load, the disease can be classified as either paucibacillary or multibacillary. M. leprae multiplies very slowly and the incubation period of the disease is about five years. Symptoms can take as long as 20 years to appear.

Leprosy is not highly infectious. It is transmitted via droplets, from the nose and mouth, during close and frequent contacts with untreated cases. Leprosy is curable and treatment provided in the early stages averts disability. The diagnosis and treatment of leprosy today is easy and most endemic countries are striving to fully integrate leprosy services into existing general health services. This is especially important for those under-served and marginalized communities most at risk from leprosy, often the poorest of the poor. 

General information about this disease



"Small bites can be big threats," experts warn on World Health Day

Mosquitoes, ticks, flies and other insects can be far more than a nuisance. The diseases they carry-malaria, dengue, yellow fever, West Nile virus, Lyme disease and many others-can cause serious illness and in some cases death. In the Americas, one out of every two people lives in an area at risk of one or more of these vector-borne diseases.

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:: Elimination and Stigma and Discrmination

Communicable Diseases and Health Analysis Department
Neglected, Tropical and Vector Borne Diseases Unit
Leprosy Program

www.paho.org/leprosy

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