A group of scientists believe they have found the possible origin of mad cow disease. Researchers underline the need to maintain precautionary measures to prevent a possible resurgence of the disease.
Several hypotheses have been put forward to explain the cause of Bovine Transmissible Spongiform Encephalopathy (BSE), the neurodegenerative disease commonly known as “mad cow disease”, which first appeared in the 1980s in the United Kingdom. However, so far, one hypothesis has been validated.
This disease belongs to a family of diseases that involve folding proteins known as prions (an infectious agent that, unlike all known ones, appears to consist solely of protein). These are neurodegenerative diseases that affect many species, including humans.
Prions are present in diseases such as scrapie, which affects sheep, or in Creutzfeldt-Jakob disease, which affects humans.
In this research, scientists at the National Institute for Agronomic Research in France injected a variant of scrapie into laboratory rats that started producing the prion of bovine origin. This experience has allowed researchers to prove that the disease has the ability to "jump" from one species to another. In addition, according to the scientific article published In PNAS, transgenic rodents developed mad cow disease.
Genetically modified mice are “a very good example of what would happen if cows were exposed to such prions,” research leader Olivier Andreoletti told AFP. These results are explained by the “presence of classic amounts of mad cow disease” which, in turn, is present in injected prions.
According to Phys.org, BSE has spread across “Europe, North America and many other countries” in a process aided by food consumption, including cereals and carcasses of animals affected by the disease. Contact with infected livestock products caused man to contract the disease, a variant of Creutzfeldt-Jakob.
Since the 1990s, Europe has introduced a number of measures to combat the spread of the disease, including the ban on animal meal and the destruction of the most contagious tissues. "These measures are still in force – but they are very expensive," says Andreoletti, arguing the need to maintain precautionary measures to prevent a possible resurgence of the disease.