Chronic wasting disease (CWD), a prion disease found in cervids (elk, deer, and moose), was first described in the 1960s and is now found in animals in at least 14 states. Despite its long history, it was unclear how the disease spread and if humans were at risk of acquiring the disease. In 2006 researchers designed and executed an experiment to determine if prions could be transmitted between cervids by contact with saliva, blood, feces, and urine. They found that CWD could be transmitted by oral contact with saliva and by blood following transfusion. This finding has raised concern among hunters and others who come in contact with cervid body fluids.
How would you design a similar experiment to identify the transmission of scrapie between sheep and possible transmission to humans? Be sure to explain the controls you would use and how you would unequivocally document the development of disease.
Read the original paper: Mathiason, C. K., et al. 2006. Infectious prions in the saliva and blood of deer with chronic wasting disease. Science 314:133.
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Prescott's Microbiology
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- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning