Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that primarily infects T lymphocytes, a type of white blood cell. It is associated with several severe diseases, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T-cell leukemia/lymphoma (ATL). The virus is transmitted through sexual contact, blood transfusion, sharing needles, and from mother to child during breastfeeding.
