However , the original idea was to distinguish leprosy patients and persons with normal blood , and he invented a skin test using the killed bacilli , the original Mitsuda reaction .
It proved very useful in the classification of leprosy .
The original idea was to distinguish leprosy patients and persons with normal blood , and he invented a skin test using the killed bacilli , the original Mitsuda reaction .
It proved very useful in the classification of leprosy .