Tropical spastic paraparesis (TSP), a progressive myelopathy predominantly
affecting the lower limbs, is currently synonymous with human T-lymphotropi
c virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis
(HAM/TSP), At the turn of the 20th century, Drs Henry Strachan and Henry Sc
ott provided the first clinical descriptions of persons with syndromes rese
mbling HAM/TSP. As H-TLV-I was not detected until 1980,(1) these historical
references likely included persons who did not have HAM/TSP, In the mid-19
80s, the association of HTLV-I with the neurologic syndrome HAM/TSP was rep
orted concurrently in patients from the Caribbean islands, Colombia, Japan,
and the Seychelles.(2-5) Using the original quotations from the seminal ar
ticles, this article traces the initial reports of this syndrome, the disco
ver) of the infectious cause, and the development of the clinical definitio
n of the syndrome.