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Lyme Disease: Observational Study

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Lyme disease is vector borne disease that is caused by the Borrelia burgdorferi bacteria. It is transmitted to humans by the nymphal stage of scapularis ticks (Levi et al, 2012). It is widespread in North America, and is often times discussed about in relation to deer population. While ticks use deer often as a reproductive host, this article discusses that deer are not the only factor that affect the prevalence of Lyme disease. Small mammals and predation play a major role in the emergence of this Lyme disease.
Three hypotheses the article discusses are the “deer hypothesis”, “small mammal hypothesis”, and the “predator hypothesis.” The first of these three appears to be what was commonly thought of when thinking of ticks and Lyme disease, …show more content…

This study design is an observational study. The research was carried out using examination and analysis of disease models and special and temporal scales between the species involved. In this study, Lyme incidents are the dependent variable and the animal abundance being looked at it the independent variable. Species were placed into groups and parameters were set up in order to facilitate examination. Lyme disease rates and information were taken from county records. Once the data was collected, mathematical formulas were used for further analysis and to get results. During the study, some proxy variables had to be used. One of these was using buck harvest to account for deer density. This was done in Virginia. This type of proxy weakens the arguments made in this study because it is only accounting for male deer and also, the number of buck harvest may not necessarily be equivalent to the entire density of deer, including those …show more content…

The data found showed that Lyme disease had in fact practically no correlation with deer abundance (Levi et al, 2012). It also showed that there was a negative correlation with foxes, which makes sense given the predator hypothesis; if there were many foxes, then there would be less small mammal hosts (Levi et al, 2012). Data also showed that coyote abundance was positively correlated with Lyme disease incidence (Levi et al, 2012). Again, this supports the predator hypothesis. As the coyote becomes the main predator in a location, as long as it continues to not prey on the small mammals, the Lyme disease incidence will increase alongside coyote abundance. As far as cause and effect in this study, the effect is the continuing emergence of Lyme disease. Given the data that has been found, the cause appears to be in the increase in coyote abundance, reducing fox abundance, and resultantly, allowing for increase in small mammal

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