Prions are misfolded proteins that can cause neurodegenerative diseases by triggering the abnormal folding of normal proteins in the brain. Unlike bacteria, viruses, or fungi, prions are not living organisms, nor do they contain genetic material like DNA or RNA. Instead, they are purely protein-based infectious agents.
Prions are responsible for a group of diseases known as transmissible spongiform encephalopathies (TSEs), which affect both humans and animals. Some examples include:
- Creutzfeldt-Jakob Disease (CJD) in humans
- Bovine Spongiform Encephalopathy (BSE), commonly known as mad cow disease, in cattle
- Scrapie in sheep and goats
In these diseases, prions accumulate in the brain, causing the formation of sponge-like holes, leading to brain damage and a range of symptoms like memory loss, difficulty moving, and ultimately death. What makes prions particularly concerning is that they are resistant to standard methods of sterilization, making them hard to eliminate. They can be transmitted through contaminated food, surgical instruments, or even by inheriting genetic mutations that produce abnormal prion proteins.