A Saving Grace

Writing 20 (Fall 2007): Science and the Not-So-Great Outdoors Professor Cary Moskovitz Not too long ago, I tried to envision the first classes I might take as a college freshman, and a writing class centered on ticks did not cross my mind. Not knowing what to expect from a course named “Science and the Not-So-Great Outdoors”, I steeled myself for overwhelmingly technical language and long passages of dense material. In a way I was not disappointed—many of the studies I found during the research phase of this paper were fairly difficult to comprehend due to medical and scientific terminology that I was not yet familiar with. Fortunately, it was not required of me to spend an excessive amount of time trying to understand all of the scientific jargon. Rather, I was able to get to the crux of the reports in a less tedious manner and my classmates were instrumental in this process. Instead of having to work directly with the four studies that form the foundation of my paper, I was able to work with their synopses and reviews, created by my classmates and me. Not only did this help me to get different perspectives of the studies as I referred back to them, but it also aided my understanding of them since the work of my classmates was not geared towards scientists or health professionals, but laypeople like me. And after much feedback and several drafts of revision, I hope I have made my paper compelling to individuals of a variety of backgrounds. Three years ago, roughly 20,000 cases of Lyme disease were confirmed in the U.S., making it the most common vector-borne disease in the country. [1] Caused by the bacterium Borrelia burgdorferi, this tick-borne disease produces symptoms that can range anywhere from a rash, chills, and body aches to joint swelling and temporary paralysis. [2] Nevertheless, a full recovery is possible with the help of antibiotics, provided that the disease is caught early. [2] Human Granulocytic Ehrlichiosis (HGE) is another tick-borne disease, first expressed in 1994. [3] What is believed to be HGE’s disease-producing agent, Ehrlichia phagocytophila, belongs to the family of bacteria that is also responsible for Rocky Mountain Spotted Fever and Typhus. [4] There is a period of about 1-2 weeks before HGE’s flu-like symptoms occur, but it is easily treated using antibiotics for approximately seven to ten days. [4,5] This disease can be found in Lyme disease-endemic areas since the Ixodes scapularis, more commonly called the deer tick or black-legged tick, is the primary vector of both Lyme disease and HGE. [6] Furthermore, it has been found that nymphal and adult female deer ticks are the chief transmitters of these diseases. [7] There is little existing data on the incidence rates of HGE, [8] but studies have shown that only 1%-3% of deer tick bites in Lyme disease-endemic areas actually result in the transmission of B. burgdorferi, even though the infectious agent can be present in as many as 15%-30% of ticks. [6,9] A likely reason for this marked disparity in incidence and prevalence rates is that individuals bitten by infected ticks tend to remove the tick(s) before the infectious agent can be transmitted. This tendency suggests that the transmission does not begin at the time of the bite. Rather, there must be a period during which the probability of the agent’s transmission is very low to nonexistent. In the same vein, though the transmission rates of diseases typically differ, several studies support the existence of a “grace period” of at least 24 hours during which the agents of both Lyme disease and HGE are not transmitted from a nymphal or adult female deer tick to its host. There is evidence for a “grace period” during which the