Spongiform Encephalopathy

Variant Creutzfeldt-Jakob disease (vCJD) is a rare and fatal human neurodegenerative condition falling under the category of Transmissible Spongiform Encephalopathy (TSE) because of having characteristic of spongy degeneration of the brain that it causes and its ability to be transmitted. First it was described in the United Kingdom in March 1996 and it has been connected with exposure to a TSE of cattle known as Bovine Spongiform Encephalopathy (BSE) sometimes called Classical BSE, having been reported first in 1986 in the United Kingdom.

The meats that consumers eat are slabs of a cow’s muscle tissue and the infectious meat is only found in the nerve tissue. Of course there is the possibility of having some of the contaminated meat passed on to the meat that consumers eat when the cows are cut, but the chances are very slim. Since this disease is contracted through eating contaminated meat, the site of infection should be in the digestive tract, yet this disease eats away at the brain and nervous system.

Although mad-cow disease is always fatal, it is not really much of a worry in the United States. There have only been four cases of mad-cow disease ever recorded in the United States. In every case, the United States Department of Agriculture has intervened and recalled tons of beef, 10,400 lbs. in the first case to be exact, in order to insure that the meat did not reach the plates of United States citizens.

Mad cow disease, also known as bovine spongiform encephalopathy (BSE), is a transmissible, slowly progressive, degenerative, and fatal disease which affects the central nervous system of adult cattle. Many researchers believe that an abnormal version of a protein normally found on cell surfaces, called a prion is the main reason to cause mad cow disease. For some still unknown reasons, this protein becomes modified and ruins the nervous system tissue, the brain and the spinal cord.

Horse slaughter has been going on for a long time now and humans have increased their horsemeat consumption because of the mad cow disease. Mad cow disease is issued from the fattening foods farmers give to their cattle. In the food are sheep’s’ bones grinded into tiny, tiny bits. Ignorant till the outburst, makers didn’t know that in sheep bones there is the virus of the dreaded disease. The disease doesn’t affect sheep as it is only in their bones but when the cows eat it, it gets into their systems and is passed on through their meat to humans.

For my paper I will be discussing in depth the responses to the questions posed at the end of the study as follows. What kinds of problems are inherent in Jolene’s research project? How would these problems affect the research results? How would you solve these problems? What should Stefanie do? What would the consequences of these actions be for Jolene? For Dr. Lee? For Stefanie

Mad Cow disease has been heavily spoken about on the international news. Our hopes are that the disease will not spread into the United States, even though several people have died from the disease.

(pg. 371 1st ¶ Biology). “The disease occurred after the individual had participated in the cannibalistic practice of eating a deceased person’s brain; the brain was evidently infected with prions. (pg. 371 1st ¶ Biology). The cannibalism was part of a funeral rite. Women and children were expected to consume a part of the brain and spinal cord, whereas men and boys were more likely to consume muscular flesh. Hence, there were more cases of CJD within the female

Another interesting finding was that CWD affects the lymph nodes first, the brain second, and shows clinical signs (drooling and weight loss) third. All those affected places no matter what lead to death. Based on their study there were four assumptions: deterministic transitions (between states), spatial homogeneity (210 sq. miles), homogenous transmission and mixing (age, sex, infection), and no migration. It is believed that CWD has been around since the late ‘60s-early ‘70s, and derived from scrapie or may be human induced. Janelle stated, “Given estimated parameters from data model is sensitive to adult survival- influenced by magnitude of transmission coefficients and harvest levels.” It was noted that in Wisconsin the DNR aren’t finding ways to manage CWD, they are letting it run its course. Also, there were no policy changes among hunting the

However, differing from the other diseases, Prion sometimes spreads through contaminated meat. In the article “Prion Diseases” it shows meats that have mad cow disease can cause prion disease. Intake of unhealthy meat is not infectious since the spread is not direct. Moreover, like Alzheimer’s, transferals through medical procedures may cause the gain of Prion Disease. Prion disease can be the result of a transfusion with a person with the disease. Furthermore, many things may take a toll on the spread of Prion disease, but it is not

Scientists determined that CWD transmission occurs when disease prions are shed by infected animals through saliva, urine, feces and natural decomposition after death. A prion is the agent that transmits TSE category diseases. In addition, CWD prions are extremely resistant to the environment, and transmission may occur directly between animals or indirectly between uninfected animals and the environment (Witkowski 3). Thus, the disease is highly contagious, as the prions are very hardy and can survive nearly anywhere. The prions adhere and bind to the substrate using competitive inhibition, or when the inhibitor binds to the active site on the substrate, kicking off and not allowing the enzyme that would normally bind to attach there. As a result, the infectious prion takes over and is what causes the transmission of the disease. Also, because the sickness is spread through feces and saliva, everywhere an infected deer eats or walks throughout the day may contain traces of contamination. Supplementary, CWD is an unfailingly fatal brain disease. Once a deer contracts the fatal illness, the life expectancy ranges anywhere from 18 to 20 months. Deer typically look healthy the first 16

Transmissible spongiform encephalopathies (TSEs), or Prion diseases, are a group of neurodegenerative disorders which include but is not limited to kuru, Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker (GSS) syndrome, and fatal familial insomnia in men, natural scrapie in sheep, goats and mufflons. The first records of neurodegenerative disease which would later be linked to Prions were made about two hundred years ago. It was in the 1950’s it was discovered that Prion disease could be transmitted horizontally, in addition to being inheritable and spontaneous. These findings were sought out by isolated tribes of the New Guinea that were suffering from high prevalence of a particular TST called Kuru. Some additional history of Prion disease dates back to the 1980’s when an increasing number of cows in the UK became infected with Mad Cow Disease also known as Bovine Spongiform Encephalopathy. This unfortunate epidemic was traced back to a food supplement that was fed to the cows, this supplement contained mean and bone meal from dead sheep. A speculation was then drawn that the BSE had been a result of the sheep that had suffered from scrapie, which is a sheep-specific Prion disease. As a result it was decided by the British government that the banning of animal derived feed supplements. This helped to decrease the disease of cattle which subsequently disrupted the spread of the disease amongst livestock and animals.

The need to discuss and consider this disease as a physiological phenomenon is due to several factors. The disease impacts adult cattle but is acquired in the

Which of the study's results or conclusions did you feel was the most critical or informative from a purely scientific perspective and why?

Ebola Virus Disease (EVD) is a rare and devastating disease that causes a public health crisis every time there is an outbreak. (JAMA) It’s most common victims are humans and primates like monkeys, chimpanzees and gorillas. EVD is caused by being infected with one of the five species of Ebola. Only four of the viruses will cause the disease to develop in people, Zaire ebolavirus, Sudan ebolavirus, Tai Forest ebolavirus, Bundibugyo virus and Reston ebolavirus. The strand of the virus that is heard about the most in the news and is responsible for the most recent out breaks in the Democratic Republic of the Congo is the Zaire species of the Ebola virus (CDC).