“Ancient disease has potential to regenerate livers, study finds (Leprosy infection benefits livers)”
Unfortunately, leprosy rots out the rest of your body.
In most cases leprosy is easily cured or at worst controlled with common anti-biotics.
One problem with this treatment maybe that the number of people susceptible to leprosy is rather small outside of the Middle East
If you can’t be infected how can the bacteria do their work to grow your liver.