Leprosy and tuberculosis vaccine design.

Tuberculosis and leprosy are bacillary infectious diseases which cause severe global health problems with approximately 50 to 60 million people suffering from tuberculosis and 10 to 15 million from leprosy. In the developing countries the currently available vaccine, Bacille Calmette-Guérin (BCG) was found to be less effective than originally thought. This disappointment, as well as recent achievements in biotechnology, has led several researchers to embark on novel avenues towards a rational vaccine design. This strategy stems from the idea that protective antigens exist which can be identified by immunological methods, expressed as recombinant gene products, and administered in a way that induces a protective T cell response.