Leprosy Training Module for Medical Officers

Incubation Period
The period between the time of entry of the organism and the time of
onset of clinical signs is called incubation period.
As such, in Leprosy, these two reference points for measuring the
incubation period are difficult to define. The former ( time of entry of the
organism ) because of the lack of adequate immunological tools and the latter
( time of onset of clinical signs ) because of the insidious nature of the onset of
Leprosy.
The incubation period in Leprosy in variable. It could be as small as 6
months or as long as 30 years. It is believed that the incubation period could
be an average of 2 – 5 years.
Summary
1. Leprosy is a chronic infectious disease caused by Mycobacterium leprae.
2. It is a public health problem because of the disabilities it produces in a
few patients.
3. India contributes to about 66 % of case load in the world.
4. The bacteria enter and exit the body through nose and mouth.
5. The incubation period is long and variable.
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