Thursday, January 20, 2011

Health Care and Mad Cow Disease

Mad cow disease is the popular term for "bovine spongiform encephalopathy" (BSE), a fatal neurodegenerative disease in cattle that causes a spongy degeneration in the brain and spinal cord. The disease is transmitted by tiny micro-organisms known as prions, according to NaturalNews.com. Five known human prion diseases exist, including Creutzfeldt-Jakob disease, as well as six non-human diseases, including scrapie, chronic wasting disease and mad cow disease (which sometimes jumps to humans through contaminated meat).

According to the Centers for Disease Control (CDC), the nature of the transmissible agent is not well understood. Currently, the most accepted theory is that the agent is a modified form of a normal protein known as prion protein. For reasons that are not yet understood, the normal prion protein changes into a pathogenic (harmful) form that then damages the central nervous system of cattle.  

According to KidsHealth.org, only certain animals can get BSE — people don't actually get mad cow disease. However, experts have found a link between BSE and a rare brain condition that affects people, called variant Creutzfeldt-Jakob disease (vCJD). Researchers believe that people who eat beef from cows that have BSE are at risk of developing a form of vCJD

A shocking recent new study by the University of Zurich Hospital has found that mad cow disease can be transmitted through the air, according to Natural News. Prior to the study, it was believed that humans could only be infected through consumption of food products from infected cows, contaminated surgical instruments or blood transfusions. The new findings raise serious questions about airborne transmission risks, particularly among people who work in science labs and meat and animal feed facilities. Most infectious diseases are spread by bacteria or viruses, which use genes to copy themselves. But prions are a third form of disease discovered in 1982, and they're made only of misfolded proteins. The misfolded proteins convert healthy proteins into long fibrils, which in turn create more prions until the host dies from destroyed brain and nervous tissue. Prion symptoms appear suddenly months or years after infection and are 100 percent fatal. The prions appear to transfer from the airways and colonize the brain directly because the immune system, which prevents the passage of prions from the digestive tract to the brain, does not recognize airborne prion infection. More research should be done to confirm these findings.

When people have vCJD, cells in the brain die until the brain eventually has a "sponge-like" appearance, according to KidsHealth.org. During this time, people with the disease gradually lose control of their mental and physical capabilities. To date, very few people have been diagnosed with vCJD. By October 2009, only 217 cases of this rare condition had been reported worldwide. Of these, most were identified in Britain. Several of the people diagnosed with the disease outside Britain — including two cases in the United States — had a history of exposure in Britain. Experts believe that the people got vCJD after eating beef products from cows that had BSE. Because vCJD is relatively new and extremely rare, experts are still learning about it.

However, researchers believe that the disease is not contagious among people. In other words, you cannot get vCJD from someone else who has it, according to Kids Health. At present, it appears that the main way people get the disease is from eating contaminated meat. Experts don't yet know exactly how long the incubation period is for vCJD (in other words, how long it takes from the time a person contracts it to the time that symptoms first appear). However, they do believe that it takes years, if not decades, from the time someone is exposed to the disease until the first signs appear. After the first signs appear, the brain can deteriorate within a year. At this time, there is no known treatment for the disease.

Current testing in the US only samples a small number of brains from all cattle slaughtered for human consumption, according to eMedicineHealth.com. Testing of brain tissue takes more than a week to deliver results. This testing is done only after the animal has been presented for slaughter. European countries use fast tests to screen many more slaughtered cattle than is done in the US. Results are obtained overnight as carcasses await approval in refrigerated warehouses before entering the food stream. Live animal tests may provide valuable information about the level of BSE in all animals, including downer cattle and cattle aged 24 months or older (those most at risk and in whom BSE is found). However, currently there is no sensitive and reliable live animal test for BSE. Thus, given the limitations of the tests available today, certain tissues of cattle infected with BSE may contain the BSE agent before a diagnostic test could indicate that the animal has BSE. Therefore, there is a great need for a sensitive and reliable test that can be done on live animals or on cattle that have been slaughtered.
 
According to WebMD.com, in affected cows, the changed proteins are found in the brain, spinal cord, and small intestine. There is no proof that these changed proteins are found in muscle meat (such as steak) or in milk. When a cow is slaughtered, parts of it are used for human food and other parts are used in animal feed. If an infected cow is slaughtered and its nerve tissue is used in cattle feed, other cows can become infected.

People can get vCJD if they eat the brain or spinal cord tissue of infected cattle. The risk is substantially greater. Variant Creutzfeldt-Jakob disease (vCJD) causes the brain to become damaged over time, and it is always fatal. Symptoms include:

--Tingling, burning, or prickling in your face, hands, feet, and legs. But there are much more common illnesses that cause these same symptoms. Having tingling in parts of your body does not mean you have vCJD.
--Dementia.
--Psychotic behavior.
--Problems moving parts of the body. As the disease gets worse, a person is no longer able to walk.
--Coma.

There is no single test to diagnose vCJD. Doctors may think that a person has vCJD based on where the person has lived and the person’s symptoms and past health. Imaging tests, such as an MRI, may be done to check for brain changes caused by vCJD. Researchers are now trying to develop a blood test that looks for vCJD. But no blood test is available at this time. A brain biopsy is the only way to confirm a diagnosis of vCJD, according to WebMD.

You can make choices to lower your risk for contracting vCJD from contaminated beef, according to eMedicineHealth. Here are some options:
•Eat poultry and fish, or choose a vegetarian diet.
•Avoid beef products that may contain bits of spinal cord or brain tissue. These include ground beef, sausage, and hot dogs. Solid pieces of muscle meat are less likely to be contaminated. Bone-in cuts such as a T-bone steak and intestine are more risky.
•If traveling to countries where BSE has been detected, such as the United Kingdom, Europe, Portugal, and Spain, don’t eat beef. Avoid having a blood transfusion overseas.
•Milk and milk products are not thought to be affected or a means of transmittal.

Always follow common sense guidelines when there is possible exposure to this disease, especially if you are traveling overseas or outside of the United States. Since there is no known cure or tests to determine possible infection, and vCJD is a sleeper disease, you may be at risk and not know it for some time. If you or a loved one experiences symptoms similar to the disease, see a physician immediately for proper diagnosis. Chances are, the resulting health care issues may be found to be other medical problems, but always seek the advice of medical professionals when you experience unusual physical or emotional problems.
 
Until next time. 

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