What type of diseases are caused by prions?

Prions are unique infectious agents composed solely of protein without any nucleic acids. They are responsible for a category of neurological conditions known as transmissible spongiform encephalopathies (TSEs), which include diseases such as Creutzfeldt-Jakob disease, mad cow disease (bovine spongiform encephalopathy), and scrapie in sheep. These diseases are characterized by the degeneration of brain tissue, resulting in severe neurological impairment and ultimately leading to death.

The term "degenerative diseases" aptly describes the mechanism of prion diseases because they lead to progressive neurological dysfunction and destruction of nerve cells. Unlike autoimmune diseases, which arise from an inappropriate immune response against the body’s own tissues, or infectious diseases associated with various pathogens like bacteria, viruses, and fungi, prion diseases specifically involve the misfolding and accumulation of prion proteins, leading to neurodegeneration. The classification as viral diseases does not apply here, as prions do not contain any viral components. Thus, identifying prion-related conditions as degenerative diseases aligns precisely with their pathological effects on the nervous system.