Mad cow disease was discovered in Britain in 1985, reached its climax in the early 1990s, and then gradually spread to western Europe, and now it has become a worldwide problem. Mad cow disease is a new type of Alzheimer's disease, which is also a new type of Creutzfeldt-Jakob disease. This is an unprecedented disease, a chronic, fatal and degenerative nervous system disease. It is caused by a pathogen whose essence is not fully understood at present-prion.
What are the characteristics of prions?
First of all, it has no nucleic acid, which can change normal protein from benign to malignant, and from non-infectious to infectious; Secondly, it has no virus form, just a fibrous thing; Third, it is resistant to all physical and chemical factors that kill the virus, and the existing disinfection methods are useless. It can be inactivated only at high temperature of 136℃ and high pressure for two hours. Fourth, the incubation period of the virus is long, with an average of 28 years from infection to onset. Once the symptoms appear for half a year, 100% will die. Fifth, the diagnosis is difficult. There are prion proteins in normal human and animal cells. Under the action of unknown reasons, its three-dimensional structure changes and becomes an infectious protein. Patients do not produce immune response and antibodies, so they cannot be monitored.
How is mad cow disease spread?
Mad cow disease may be transmitted to humans through beef and beef products, especially internal organs and bone marrow.
The spread of mad cow disease, one is iatrogenic infection, such as blood transfusion, medical equipment, brain surgery, organ transplantation, biological products infection and so on. Pituitary growth hormone for treating dwarfism and gonadal hormone for treating infertility are extracted from a large number of corpses. If one of the bodies is creutzfeldt-Jakob disease, all products will be contaminated. Hundreds of cases have appeared in the United States, Britain, France and Australia. The second is bovine-derived drugs. Drugs made from brain, spinal cord, blood and bone glue of sick cattle can be infected with mad cow disease.
What diseases can prions cause?
Prions can cause more than 20 diseases in humans and animals. Infringers include Alzheimer's Harmo's disease (CJD), Kuru's disease and Alzheimer's Harmo's disease. Simmons syndrome, fatal familial insomnia and mad cow disease (variant creutzfeldt-Jakob disease). Different from the usual Creutzfeldt-Jakob disease, mad cow disease mainly affects young people, with an average age of 28 years, and the youngest is 14.
How to eliminate mad cow disease in China
At present, mad cow disease has not been found in China, but we must be vigilant. What to do: First, plug the loopholes. Customs entrances and exits should be blocked. Second, check the internal sources. We should check whether our local cattle and sheep have diseases caused by prions. Prions can break population boundaries. It is now found that 18 species of animals will be infected, of which 16 species will be infected through the digestive tract. Third, a strong foundation. Strengthen basic research. At present, prion research has been included in the national "863" project, and has also been funded by the National Natural Science Foundation, and a number of diagnostic methods with intellectual property rights have been established. (transferred from Beijing Youth Daily)