Human T-cell lymphotropic virus type 1 or human T-lymphotropic virus type 1 (HTLV-I), also called the adult T-cell lymphoma virus type 1, is a retrovirus of the human T-lymphotropic virus (HTLV) family that has been implicated in several kinds of diseases including very aggressive adult T-cell lymphoma (ATL), HTLV-I-associated myelopathy, uveitis, strongyloides stercoralis hyper-infection and some other diseases.