CD4 and tropical spastic paraparesis: The incidence of ATLL and HAM/TSP varies from 0.5% to 10% among HTLV-1 infected subjects, increasing morbidity and mortality rates [9] Additionally, treatment of coinfections, such as HIV and HCV, can be delayed due to HTLV-1 promoting an inefficacious increase in CD4+ cells, leading to a delay in antiretroviral therapy (ART) initiation and, possibly, inefficacious HCV clearance [10,11,12,13].