Recent advances in microbiology in leprosy

The recent advances in microbiology of leprosy are reviewed. Till now the leprosy bacillus had not been cultivated in laboratory media; the recent claims of success have not been confirmed. There has been a breakthrough in the experimental transmission of leprosy to experimental animals--the white mice, the immune depressed white mice, and the nine-banded armadillo. Apart from providing definite proof for the causative relationship of the bacillus discovered by Hansen and the disease leprosy, the experimental transmission to animals have considerably advances our knowledge about the disease. The mouse has provided a suitable model for screening of antileprosy drugs, detecting development of drug resistance, ascertaining viability of the bacilli and determining the genuineness of a supposed culture of the leprosy bacillus. The armadillo has provided a model for making basic studies of the disease as it occurs in man. Further, the generalised infection in armadillo has provided large amounts of leprosy bacilli for preparing standardised lepromin, for preparing a specific skin-testing antigen containing the active protein fraction of the bacillus, and a step towards the production of a vaccine against leprosy. It is interesting to note that the fact that the protein fraction of the bacillus was responsible for the positive lepromin reaction was discovered by Dharmendra far back in 1941.