Did You Know?As a part of the funeral ritual, people in New Guinea ate brains of dead people. This resulted in a disease called Kuru (central nervous system disorder) which is associated with mad cow disease in cows.
Medically known as Bovine Spongiform Encephalopathy (BSE), this ailment affects the central nervous system (CNS) of cattle. Mad cow disease belongs to a group of Transmissible Spongiform Encephalopathies (TSE). This is a group of neurodegenerative disorders that affect animals and humans. In animals, other related diseases are scrapie (sheep) and feline spongiform encephalopathy (cats). In humans, the diseases are Gerstmann-Sträussler-Scheinker syndrome (GSS) and fatal familial insomnia (FFI). It is believed that mad cow disease is caused by the presence and actions of prions, which are infectious agents that comprise protein in an abnormal form.
The transmission of these infectious agents is via misfolding or incorrect protein folding. They are generally found in the brain, spinal cord, small intestine, and blood of cattle. They can also be found in the lymph nodes, spleen, and bone marrow of the affected organism. Some scientists are also of the opinion that proteins present in the body convert into prions due to the presence of some kind of virus. However, this theory has not been substantiated by studies. Prions damage the CNS, making sponge-like holes in these parts. This results in degeneration of nerve cells, which eventually leads to the death of the organism.
Symptoms in Humans
Studies and lab data have shown a striking relation between BSE and variant Creutzfeldt-Jakob disease (vCJD) in humans. Variant CJD is a neurodegenerative disease in humans which is usually fatal. It is linked to consumption of infected meat or meat products. The disease manifests itself in the following manner:
- The earliest symptoms include depression, insomnia, and anxiety.
- The person may look withdrawn and in a confused state of mind.
- Significant changes in the personality and behavior of the individual.
- The person may also experience muscle spasms, i.e. involuntary muscle contractions that are very painful.
- As the condition of the patient worsens, he loses muscle control and coordination, and may also face problems with vision (blurred vision) and memory.
- Temporary memory loss is another sign which makes it difficult for the patient to recognize people. Also, it makes daily tasks cumbersome.
- The affected individual may experience a tingling sensation in the feet, hands, face, and legs.
- He may develop dementia which can make him mentally and physically weak.
- During the final stages of the ailment, the patient may go into a coma which finally leads to death. A person reaches the final stage within 6 months to one year after the onset of the symptoms.
Mad cow disease is invariably a disease of cattle. Some of the clinical signs are listed below:
- Difficulty in standing and walking.
- Problems with muscle coordination.
- A slight change in the behavior of the organism is observed.
- Sudden weight loss.
- A significant decrease in milk production is also observed.
As mentioned earlier, the causative agent for this disease is a prion. It cannot be transferred from one organism to the other by physical contact. However, it can make its way into humans and animals:
- In slaughterhouses, the remains of animals are disposed without any tests. These wastes/byproducts are fed to cattle as a cheap source of protein supplement. When they are fed infected (with prions) animal remains, the prions get transferred in them.
- When human beings consume meat infected with BSE, it puts them at a risk of contracting this disease too.
- There have been cases where variant Creutzfeldt-Jakob disease has occurred in people without any known reason, including those who are vegetarians. Genetic mutation, which is hereditary, is also said to cause this disease in humans.
- Apart from this, infected blood transfusion, transplantation of tissues containing prions, and exposure to infected surgical instruments can lead to the development of this disease in human beings.
There is no absolute technique or physical test to diagnose the disease. However, the doctor may advise a complete blood checkup along with MRI or PET scan. He may also recommend a brain biopsy to check the changes caused in the brain.
Sadly, there is No effective treatment or cure for the disease. Research is still going on to find medication that would help in curing this disease in humans as well as animals. The patient may be given certain medication to control the symptoms. Providing love, care, and moral support will help the person cope with the disease.
It is advisable to take certain precautionary measures to prevent this medical condition. Limit your consumption of red meat. Heating, boiling, irradiation, or chemical reagents have failed to kill causative prions. Hence, cooking the infected meat does not ensure a safe consumption. Turning into a vegetarian is also a good idea to prevent this disease. If you notice any of the symptoms mentioned above, consult a doctor as soon as possible.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.