01906nas a2200325   4500000000100000008004100001260001700042653001200059653001500071653002200086653001500108653002300123653001100146653001100157653001200168653000900180653002500189653001100214653002200225653002300247100001400270700001300284700001300297700001300310245004700323300001100370490000600381520117900387022001401566       1987                            d  c1987 May-Jun10aAnimals10aArmadillos10aArthropod Vectors10aArthropods10aDisease Reservoirs10aFemale10aHumans10aleprosy10aMale10aMycobacterium leprae10aPlants10aSoil Microbiology10aWater Microbiology1 aBlake L A1 aWest B C1 aLary C H1 aTodd J R00aEnvironmental nonhuman sources of leprosy.  a562-770 v93 a<p>Leprosy has been considered to occur only after exposure to a human case. However, evidence has been accumulating that this conventional view is wrong and that an environmental nonhuman source is critical to some human infections with Mycobacterium leprae. Observations, some of which date back to the nineteenth century, support soil, vegetation, water, arthropods, and armadillos (Dasypus novemcinctus) as environmental sources of leprosy. Disparate clinical, epidemiologic, and microbiologic evidence has been critically reviewed in light of the fact that 50%-70% of sporadic cases of leprosy in well-studied populations occur in persons who have had no known contact with human leprosy. Historical data and current information alike substantiate the concept of nonhuman sources of the disease; recent observations with monoclonal antibody have shown that phenolic glycolipid-I antigen, which is unique to the M. leprae cell wall, is present in soil. In the absence of a technique for in vitro cultivation, indirect methods and the body of observations reviewed here persuasively favor but do not prove the existence of environmental nonhuman sources of M. leprae.</p>  a0162-0886