Leprosy. Mycobacteriumleprae

Transcription

1 Leprosy Mycobacteriumleprae

2 Quick Reference Environment: human, mice, nine-banded armadillo Microorganism: Gram + rod Spore former: NO Motile: NO Susceptibility: anyone Communicability: infectious Exposure: exposure to skin Incubation: years Primary Treatment: antibiotics; multi-drug treatment Prognosis: antibiotics keep disfigurement to a minimum Quarantine recommended: occasionally ( This is a Small island off the Upolu coast once designated as a leper colony )

3 Taxonomy Kingdom: Monera Phylum: Schizophyta Class: Actinomycetes Order: Actinomycetales Family: Mycobacteriaceae Genus: Mycobacterium Species: Leprea

4 The genome of the Myrcobacteria leprae 1 8 µm long and µm wide aerobic nonsporeformers have a cell wall that is rich in longchain fatty acid esters known as "mycolic acids" that are attached to the cell wall through arabinogalactan Mycolic acids are chemically related to wax and give the colonies their characteristic waxy appearance, and the cells, a tendency to clump and resist dispersion Gram Positive all mycobacteria grow slowly with generation times that range from 2 hours for M. smegmatis to 12 days for M. leprae. Physiology

5 Diagnostic Tests the only methods to propagate M. leprae bacilli are via animal infections with either 9-banded armadillos or severe combined immunodeficiency (SCID) mice. Growth of sufficient bacilli for laboratory manipulation takes approximately one year, inasmuch as the generation time for this organism is approximately 14 days in animal tissues.

6 Incubation children younger than two years do not have leprosy symptoms. In addition, people residing in nonendemic countries who have visited a site with endemic leprosy may develop the disease many years after the initial exposure Leprosy is a chronic disease with a long incubation period the incubation period is estimated to range from 2 12 years ( can be longer). Like those infected with TB, only about 10% of those infected with leprosy go on to develop the disease

7 Leprosy Symptoms Leprosy is also known as Hansen's disease. Caused by a germ similar to that which causes tuberculosis. It attacks the nerves of the hands, feet and face. If left untreated can take away the ability to move fingers, toes and eyelids. It can also destroy the ability to feel pain so those affected are prone to injuries and burns. The longer the disease is left undetected, the more likely it is that the deformities, so often associated with leprosy, will occur.

8 Latest Mortality and Morbidity Reports Many people tend to think of leprosy as a biblical disease. The truth is that the World Health Organization (WHO) still lists leprosy as one of the major health problems of developing countries including India, Brazil, Africa, Nepal and Bangladesh WHO Region Cases on treatment New Cases Detected in 2002 Africa 53,888 48,248 In 2002 over 610,000 people were diagnosed with leprosy. At that rate the number of new cases found this year would be Americas 75,686 39,939 Eastern Med. 7,899 4,665 S.E. Asia 385, ,632 Western Pacific 11,335 7,154 Europe Total 534, ,672 Source: World Health Organization 2003 (figures shown for 110 reporting countries)

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10 The Cure The good news is that today leprosy can be cured. A course of pills, called Multi-Drug Therapy (MDT), cures most patients in 6 months, and the more infectious patients within 1 year. If treatment is started early deformities and disabilities can be prevented and social stigmatization avoided. The effects can be incredibly dramatic as the photograph below shows

11 References Mycobacterium leprae (leprosy). BEATRICE SAVIOLA WILLIAM BISHAI. The Genus Mycobacterium Medical. The Prokaryotes: an evolving electronic resource for the microbiological community. 1991, Springer-Verlag New York, LLC Lepra. What is Leprosy.