HTLV-1-associated myelopathy (HAM) is a neurological condition caused by the human T-lymphotropic virus type 1 (HTLV-1). This virus primarily affects the spinal cord, leading to symptoms such as weakness, stiffness, and pain in the legs. It can also cause difficulties with walking and bladder control. The condition is a progressive disorder, meaning symptoms can worsen over time. Diagnosis typically involves clinical evaluation and tests to detect HTLV-1. While there is no cure, treatments focus on managing symptoms and improving quality of life for those affected.