Naked Science Forum
Life Sciences => Physiology & Medicine => Topic started by: MrBassman on 05/10/2005 21:07:49
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We see media stories about new diseases quite often these days.
Mad Cow, SARS, Bird Flu, Black Head (turkey disease)...
They threaten humanity or a segment of our food supply.
If you look at it historically, are there more diseases
popping up these days or is it just the media that makes
us take notice?
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Most 'new' diseases probably aren't new, in an absolute sense, but just new to 'us'.
In most, if not all, infectious diseases there needs to be a natural reservoir for the disease pathogen, and in many cases this reservoir seems to have been, at least initially, geographically located i.e. the disease appears to have a geographic origin. As humanity has increased in numbers it has lead to greater geographical spreading, which in turn, has lead to humans moving into new geographical regions and encountering the diseases. At the same time, humanity has become more mobile, so once the disease has been encountered, this greater degree of mobility leads to the disease being exported away from the origin via infected humans and trade animals/goods.
Some Epidemiologists suspect that it is likely that there are still a number of as yet undiscovered disease reservoirs waiting to be encountered in regions that have remained largely unexplored i.e rain forests, and that further commercialisation and exploitation of the rain forests will eventually lead to encounters with these 'new' diseases.