Through a rationale used in thermodynamics some "states" or "compartments" in the natural history of Tuberculoses are defined. Based on macroscopic changes observed in the total system an attempt is made to quantify the dynamics of these changes in the following "states": "virgin of infection", "infected" and "sick". A new way to calculate the risk of becoming infected by Tuberculosis, following the laws which govern the variation of the contents in a system of compartments, is presented. A sketch showing the relationships among the considered "states", the equations of the dynamics of them and a formula to calculate the risk of infection is also presented.
Tuberculosis; Tuberculosis; Epidemiology
