Leprosy evokes Biblical images of nose-less, limbless, deformed outcasts living in squalor. The fact is that leprosy—or Hansen’s disease as it is officially called—has never really gone away, but has morphed into something often mild and very treatable right here in Louisiana.
Hansen’s disease is caused by Mycobacterium leprae, a slow-growing bacteria this is partial to the skin, mucous membranes, nerves, eyes and bones. If left unchecked, the germ damages the peripheral nerves, leaving the sufferer insensitive to pain. It is recurrent trauma and tissue destruction, rather than erosion by the bacteria itself, that lead to loss of extremities.
Leprosy has been documented in Louisiana since colonial days, and was traditionally limited to the “Acadian Triangle,” or the French-speaking parishes of South Louisiana and New Orleans. The number of cases increased to the point that the famous leprosarium at Carville was established in 1880, and taken over by the U.S. government in 1921. From the 1930’s to the 1960’s, the number of cases progressively declined and stabilized, resulting in the closure of Carville as a leprosarium in the mid 1980’s. From the 1960’s, the downward trend, however, has been replaced by a slow but steady increase in the number of cases, notably outside of the traditional region of South Louisiana.
The exact cause of this increase is not entirely clear, but may be associated with exposure to the nine-banded armadillo. The temperature of armadillo footpads is about the same as human skin, and about 5 to 10% of these animals appear to be susceptible to leprosy. The germ grows on their footpads, and can contaminate the soil and air surrounding an infected animal. Contact with armadillos, rather than with close family contacts as in the past, appears to be the only source suggested in over 50% of newly diagnosed cases.
Despite its fearsome reputation, Hansen’s disease is very treatable. A simple antibiotic regimen (with Dapsone and Rifampin, with or without Clofazimine) will render the patient incapable of spreading the disease within a couple of weeks. Treatment course depends on response and can last months or years, but without institutionalization and with no risk to surrounding family, friends or co-workers.
Most leprosy cases in Louisiana are native-born citizens (94%), mostly white (77%) and mostly male. Time to diagnosis has decreased dramatically, with most cases being diagnosed within a year of onset. The presentation varies from a few light-colored skin patches (tuberculoid) to multiple nodules, plaques and involvement of the nasal mucosa associated with stuffiness and nose bleeds (lepromatous). A skin biopsy, with special stains, confirms the diagnosis.
Because it is relatively rare, many physicians do not think about leprosy. It should always be considered in immigrants, residents of Louisiana or Texas, or those with foreign travel who present with localized patches of light-colored skin, especially if associated with thickened nerves and sensory loss. Hansen’s disease, while sometimes not considered, is easy to treat and certainly not the dreaded Biblical disease of bygone days.