Tropical Spastic Paraparesis - History

History

For several decades, the term tropical spastic paraparesis was used to describe a chronic and progressive clinical syndrome that affected adults living in equatorial areas of the world. This condition was initially thought to be associated with infectious agents (such as Treponema pertenue and Treponema pallidum, which cause inflammation of the central nervous system) and with chronic nutritional deficiencies (such as avitaminosis) or exposure to potentially toxic foods (such as bitter cassava). Neurological and modern neuroepidemiological studies found that in some individuals no single cause could explain the progressive weakness, sensory disturbance, and sphincter dysfunction that affected individuals with TSP. In spite of public health programs created to eradicate the above-mentioned infectious and nutritional conditions in the tropics, large numbers of people continued to be affected.

During the mid-1980s, an important association between the first human retrovirus-human T-cell lymphotrophic virus type 1 (also known as HTLV-1)-and idiopathic TSP (idiopathic means of unknown origin) was established. Since then, this condition has been named HTLV-1-associated myelopathy/tropical spastic paraparesis or HAM/TSP, and scientists now understand that it is a condition caused by a virus that results in immune dysfunction.