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Comparing Ebola to past epidemics, there might be a similar evolutionary change. Taking the Plague for example, yersinia pestis found a vector in the flee, as carried by rats, and thus tended to spread along costal trade routs, if history serves us correctly, starting along the trade routs from the East. Plague was infectious, first relying on flees, then merely close contact, but evolving in a population devoid of resistance, it became pneumonic spreading with devastating consequences and speed. Later as uninfected persons became scares, the yersinia bacillus evolved back to a less virulent and less lethal form insuring greater sustainability. Today, yersinia can be found in a less virulent form among high prairie Marmots in Colorado.
The capacity to make that evolutionary change from infectious to pneumonic and back, could be through mutation or by the inherent capacity of its genome, driven by natural selection. Survival and procreation were best served by a change in virulence adapting to the availability and circumstances of the victims and the environment. An unprotected abundant population in close proximity favored virulence, whilst a more sparse target population with emerging resistance favored low virulence, prolonged illness with greater chance to spread or just lie low in a sustained reservoir.
Ebola in its present form, rapidly fatal and highly infectious in a crowded, unprotected population has little need to evolve other than the opportunity to do so. However, given its rapid spread, the crowded vulnerable population and a current strategy to enforce isolation and sanitary precautions as a means of control, one might worry about Ebola's chance of going pneumonic, thus leaping the barriers of isolation and protective sanitation to better exploit the target rich environment of a crowded and unprotected population.
I wonder what troops will accomplish in containing Ebola. We might better send doctors, and even so, containment might in itself trigger a more virulent and less containable spread. As a virus, Ebola might have within its DNA or gain by mutation the capacity to spread more like Small Pox. I think of the epidemic among the troops following WWI.
Comparing Ebola to past epidemics, there might be a similar evolutionary change. Taking the Plague for example, yersinia pestis found a vector in the flee, as carried by rats, and thus tended to spread along costal trade routs, if history serves us correctly, starting along the trade routs from the East. Plague was infectious, first relying on flees, then merely close contact, but evolving in a population devoid of resistance, it became pneumonic spreading with devastating consequences and speed. Later as uninfected persons became scares, the yersinia bacillus evolved back to a less virulent and less lethal form insuring greater sustainability. Today, yersinia can be found in a less virulent form among high prairie Marmots in Colorado.
The capacity to make that evolutionary change from infectious to pneumonic and back, could be through mutation or by the inherent capacity of its genome, driven by natural selection. Survival and procreation were best served by a change in virulence adapting to the availability and circumstances of the victims and the environment. An unprotected abundant population in close proximity favored virulence, whilst a more sparse target population with emerging resistance favored low virulence, prolonged illness with greater chance to spread or just lie low in a sustained reservoir.
Ebola in its present form, rapidly fatal and highly infectious in a crowded, unprotected population has little need to evolve other than the opportunity to do so. However, given its rapid spread, the crowded vulnerable population and a current strategy to enforce isolation and sanitary precautions as a means of control, one might worry about Ebola's chance of going pneumonic, thus leaping the barriers of isolation and protective sanitation to better exploit the target rich environment of a crowded and unprotected population.
I wonder what troops will accomplish in containing Ebola. We might better send doctors, and even so, containment might in itself trigger a more virulent and less containable spread. As a virus, Ebola might have within its DNA or gain by mutation the capacity to spread more like Small Pox. I think of the epidemic among the troops following WWI.
On the brighter side, a vaccine and experimental anti virus drugs appear to be in the offing.
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