In days of old, when knights were bold, et cetera, leprosy was thought to be highly contagious, justifying warehousing its sufferers as far away from the rest of the world as possible. This, of course, was wrong:
The illness can now readily be cured through a sustained course of antibiotics, yet the basic nature of the microbial culprit, a waxy, rod-shaped character called Mycobacterium leprae, is still being sketched out. New research suggests that the leprosy parasite is a paradox encapsulated at once rugged and feeble, exacting and inept.
One research group recently proposed that leprosy may be the oldest infectious disease to go specifically for human beings, with origins dating back millions of years, certainly suggesting a pathogen of formidable persistence.
Yet scientists have also found that the leprosy bacillus is remarkably poor at migrating between human hosts. It dies quickly outside the body a couple of hours on a lab slide, and that’s it and about 95 percent of people appear immune to it.
One less thing to worry about for nineteen of you, anyway.
Wikipedia yielded up this gem:
Leprosy was once believed to be highly contagious and was treated with mercury all of which applied to syphilis, which was first described in 1530. It is possible that many early cases thought to be leprosy could actually have been syphilis. Effective treatment first appeared in the late 1940s.
This, though, is the bit that worries me:
Armadillos are now a reservoir for the disease, and in coastal marsh habitats where population densities of the animal can be high, 20 percent or more of the armadillos are thought to be infected with M. leprae and capable of passing it on to susceptible people. Of the 200 cases of leprosy diagnosed annually in the United States, most are thought to stem from contact with armadillos, although the precise route of transmission remains unclear.
I can only hope that it’s not the same route of transmission one usually finds with syphilis.