HTLV-associated myelopathy (HAM) is a neurological condition caused by the human T-lymphotropic virus type I (HTLV-I). It primarily affects the spinal cord, leading to symptoms such as weakness, stiffness, and difficulty walking. The condition is a result of inflammation and damage to the spinal cord's nerve cells. HAM typically develops years after initial infection with HTLV-I, which is transmitted through blood, sexual contact, or from mother to child during childbirth or breastfeeding. Diagnosis is based on clinical symptoms, imaging studies, and laboratory tests to detect the virus. Treatment focuses on managing symptoms and improving quality of life.