- While covering Chapter 7 we discussed the concept of an emerging disease. Today, as we are living through the extreme consequences of just such an emerging disease, much of the worlds attention is (rightly) focused on how we can limit the impact of COVID-19 on the human population and how we might eventually reduce or eliminate its ill effects.
However, thinking scientifically, it is just as important to consider how COVID-19 emerged in the first place and how, or even if, it might be possible to prevent another pandemic like this from ever emerging again.
When we first talked about emerging diseases, we said that they were often zoonotic (diseases that can infect multiple species) or evolved forms of diseases from other animals. So far, the evidence gathered from SARS-CoV-2 (the virus that causes COVID-19) indicates that, in this case, it was likely a combination of both. The Coronavirus strain that gave rise to SARS-CoV-2 can infect bats, pangolins, and, if recent reports are correct, dogs and tigers. It also appears to have evolved since it first emerged as a human pathogen during the SARS epidemic of the early 2000s.
The question remains: why do diseases emerge? Is it the case that new diseases are constantly evolving to infect new hosts, and those hosts are evolving to resist these diseases? Or is human activity and habitat loss responsible for pushing organisms out of their fundamental niches, thus causing organisms that normally wouldn’t interact to come in contact with each other, accelerating the evolution of new pathogens?
The final scene of the movie Contagion (spoiler alert) shows a sequence of events beginning with the harvesting of a tree and leading up to the infection of one of the main characters with the emergent disease that is the focus of the movie. The implication being that habitat destruction was directly responsible for the outbreak. This is not just the construct of some Hollywood writer’s imagination, though. The producers of “Contagion” consulted with the CDC and one of the epidemiologists responsible for eradicating smallpox to ensure it was as scientifically accurate as possible.
While it is too soon to say, for certain, whether COVID-19 will be linked directly to habitat destruction, we can form a hypothesis against which we can gather evidence:
The emergence of novel diseases is accelerated by human-caused habitat destruction. Therefore the best way to prevent novel diseases from emerging in the future is to reduce the loss of habitat and specifically monitor locations where habitat loss is greatest.
Your assignment for this term paper is to choose a minimum of 3 of the sources listed below, read or watch or listen to the evidence presented, and consider whether the evidence supports or refutes this hypothesis.
Then, you are to prepare a 5 page essay covering the following points:- For each of the sources you considered:
- A summary of the evidence presented.
- How the evidence relates to the role of habitat destruction in the emergence of novel human diseases.
- Whether the evidence supports or refutes the hypothesis presented above.
- Based on your own synthesis of the evidence presented by the sources you considered:
- Overall, is the hypothesis supported or refuted?
- What additional evidence and/or experiments would you gather/perform to further test the hypothesis?
- Whether you conclude that the hypothesis is supported or refuted will not affect your grade on the term paper. Rather, it is important that you demonstrate that you can consider evidence impartially and evaluate it on its scientific merits.You must work individually. You must cite the sources you considered, using APA style, in a “References” section at the end of your paper. Your paper should be a minimum of 5 pages, not including references or any cover pages, double-spaced, 12pt font. You must turn in your paper using the “Turnitin” link included at the end of this assignment by April 16
- For each of the sources you considered: