Prions: Protein That Acts a Virus Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), represent a rare and devastating group of brain disorders that can affect both humans and animals. What makes these diseases particularly unique in the medical world is their cause: they are triggered by prions, which are normal proteins found in the brain that, for reasons not fully understood, suddenly twist and fold into an abnormal shape. This misfolded prion then acts as a template, prompting other healthy proteins to misfold in the same way, leading to a self-propagating and destructive cascade throughout the brain. As these abnormal prions accumulate, they cause progressive damage by creating tiny holes in the brain tissue. When examined under a microscope, the brain tissue resembles a sponge full of small holes, which is where the term “spongiform” comes from. The onset of these diseases is typically rapid and, tragically, mostly seen in older adult...