MP Diagnostics HTLV Blot 2.4 Post-Market Clinical Study

Inclusion Criteria: All Specimens: * Male or female * Biorepository specimen de-identified of PHI * Specimen meets HTLV Blot 2.4 labeling collection/handling criteria HTLV Positive Specimens: Specimens with a known positive infection of HTLV I, HTLV II or HTLV I/II Neurological Disorders: Specimens with a diagnosis or symptoms consistent with any of the following neurological disorders: * Acute Disseminated Encephalitis * Amyotrophic Lateral Sclerosis (ALS) * Autonomic Dysfunction * Conus Medularis Syndrome * Chronic Inflammatory Demyelinating Polyneuropathy * Dermatomyositis * HTLV associated myelopathy-tropical spastic paraparesis (HAM-TSP) * Meningitis * Mild Cognitive Impairment * Multiple Sclerosis (MS) * Polymyositis * Spastic Paraparesis * Sciatica Exclusion Criteria: HTLV Infected: * specimens with a known infection or history of HIV, HCV or HBV * specimens not meeting specimen labeling collection / handling criteria Neurological Disorders * specimens not meeting specimen labeling collection / handling criteria