New Tick Disease identified in NJ Woman
Are there such things as “New Diseases”?
Quick answer: Probably not. In his seminal 1997 work “Guns, site Germs and Steel: the Fate of Human Societies” author Jared Diamond ( Amazon Listing ) describes to the reader the cultural and developmental pressures that creates endemic disease as we know it today. Microbes that were essentially contained within the animal world evolving and adapting to human biology as a result of our pastoral legacy, when our ancestors created livestock from wild animals through domestication and selective breeding.
The unique relation ships between diseases and the vectors that carry them have been evolving for millennia if not eons and have shaped human history before history was even recorded. Not only was disease resistance integral in the dispersal of early humans (and proto-humans) it has reared its ugly head several times throughout recorded history: The Plague Epidemics of the Middle ages and the fleas that spread it, Mosquito borne Yellow fever that almost halted the construction of the Panama canal in the early 20th century and the Malaria carrying mosquitoes that kill up to a million people a year up to modern times.
These events were not the evolution of a new disease (although diseases, especially viruses, are constantly modifying their genetic structure to remain competitive), it was simply the interaction of non-inoculated peoples with a pre-existing disease reservoir, i.e. European descended humans living in a central American rainforest for which they were not adapted, or the introduction of and Asiatic microbe to previously unexposed persons of, again, European descent.
So, considering the interaction of diseases, humans and the insects that complete the link, we are left only to wonder what causative factors resulted in this discovery? A few options present themselves:
First, a true genetic change, an evolutionary step from a related disease into the strain currently identified. Although totally possible, would we be lucky enough to literally witness evolution before our very eyes? A doubtful hypothesis, certainly…
Second, the importation of a previously unknown disease vector into an environment. Considering the presence of both humans and ticks in the local environment in NJ for thousands of years, practically impossible.
So lastly, and most likely, we are looking at the introduction of a foreign pathogen into a previously unexposed host. To prove this hypothesis, we would need to trace the epidemiology and spread of this particular microbe by diagnosis to try and find the point of origin, an extremely difficult task considering the recency with which this particular disease was described. It would seem that when we apply Occam’s Razor to this question, we trim away the fat of the first two possibilities fairly quickly.
In this world of fast travel and shipping we are constantly introducing potential pathogens, vectors and victims. We are making connections between peoples and environments at lightning speeds and some times these connections result in the importation of more than just trade goods or immigrants. Although we are a little late in the game to see a “new” smallpox or polio (as these hugely endemic disease have already made their rounds of human society) the chances of a small, non-fatal pathogens being “discovered” is very high, as modern medical science comes to understand diseases in their minutiae and describe the previously encountered ones.