MAD COW DISEASE. This disease is also called Creutzfeldt–Jakob disease. It took the lives of several million people over the past few decades. Prions are the carriers of the disease. These abnormal proteins are able to affect the spinal cord and brain. A human may become infected even after eating a tiny piece of the contaminated meat. Apart from that the infection can penetrate with the saliva of the sick cow or pass from mother to child. There are also cases when the bites of bats provoked the disease. The first symptom is itching and burning followed by depression, fear of death, nightmares, apathy, rapid pulse and thirst.