Hello,
I am Mycobacterium leprae and I cause leprosy.
I am similar to Mycobacterium tuberculosis but much fussier that my tuberculosis causing relative. I cannot infect many hosts and am difficult to grow in the lab. At some point, I lost the ability to survive on my own and now need the sanctuary of the host cell in which I live. This has occurred through something known as reductive evolution, which involves the loss of genes over time which are not absolutely required for survival. I say, if I can get it from my host, why bother making it myself.
It is a common myth that I cause tissue death, resulting in fingers and other bits dropping off my victims. In fact, your own immune system damages your nerves while trying to kill me, and this causes a loss of feeling in the extremities. This means that any injuries aren't detected by the body and can deteriorate.
To study me, human scientists have to use armadillos as I can survive in these unfortunate creatures as well as in humans. I have the longest doubling time of any bacterium studied. While something like E. coli can divide in 20 minutes, I need 27 hours. This slow growth means its really hard to kill me and antibiotics typically need to be taken for more than a year to clear an infection. A big problem is the social taboo associated with my disease, with sufferers being considered unclean or cursed by the Gods. If you know you will be made an outcast if people know you have leprosy, you're very unlikely to come forward and get treatment for what is actually a completely curable disease.
