The diagnosis that ultimately resulted — leprosy — turned the Blanchards’ world upside down and rippled through the lives of many people they knew or had contact with. It also raised issues that are often confronted when any contagious disease is diagnosed, particularly one with scary connotations: What precautions should be taken to protect the rights of the affected individual as well as the health of the community?
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For the Blanchards, some of the answers lay almost literally in their back yard. Baton Rouge is home to the National Hansen’s Disease (Leprosy) Clinical Center, part of the U.S. Public Health Service.
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About 300,000 new cases of leprosy are diagnosed annually, according to the World Health Organization. Now known as Hansen’s disease, after the Norwegian scientist who discovered the mycobacterium that causes the illness, it affects about 2 million to 3 million people worldwide.

Where it is left untreated, Hansen’s disease is a leading cause of disability and devastating deformity. It remains endemic in Bangladesh, India, Brazil and elsewhere. In the United States, roughly 6,000 people have the disease. One hundred to two hundred new cases are reported annually, and, like BB Blanchard, about two dozen of those new patients have never been beyond U.S. borders.
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How transmission occurs is a mystery. Humans and the armadillo are the only two creatures known to get the disease. No one knows where the microbe hides in nature, although the suspicion is that the leprosy mycobacterium may be airborne like its bacterial cousin, tuberculosis.

Most people think of leprosy as a skin disease. But the rash that BB Blanchard had and the disfiguring lesions often associated with it are just a symptom. The mycobacteria burrow into nerves, where they often remain undetected for years or even decades.