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| Choosing the road less taken can make all the difference. (Robert Frost) |
“About
60 percent of all human diseases and 75 percent of all emerging
infectious diseases
are
zoonotic, according to the researchers. Most human infections with
zoonoses come from livestock, including pigs, chickens, cattle,
goats, sheep and camels.”
(https://www.livescience.com/21426-global-zoonoses-diseases-hotspots.html)
I
don’t often venture into the medical sciences areas,
mainly because my ignorance on the finer points would trip me up
pretty quickly. Recent reading about the decline and near-decimation
of the ancient Aztec, Mayan, Cherokee and Incan civilizations (in,
particularly, Ronald Wright’s Stolen
Continents)
piqued
my interest in zoonotics, the branch of medicine that studies the
transmission of infection from animal to human. Most of us remember
the near panic surrounding Hanta virus, an infection endemic—although
harmless—to Deer Mice but deadly to humans not possessing an
evolved immunity. We could add Aids, Avian ‘Flu, etc., etc.
Zoonoses
hitchhiked to America from Europe and Asia aboard explorers’ and
traders’ sailing ships in the 15th,
16th,
and 17th
Centuries. American natives hadn’t developed immunity to these
hitchhikers because they didn’t exist in the New World and so
populations were decimated; whole cities like Aztec Tenochtitlan
(present-day Mexico City) were felled primarily by Zoonoses, not by a
superior civilization.
The transfer
of Zoonotic infection, of course, is significantly enhanced by
proximity; the domestication of species has ensured that humans and a
variety of animal species share common territory. As
hunter-gatherers, humans would have suffered illness, but the
likelihood of zoonotic virus/bacterial transmission was lessened by
the infrequency of contact.
We have known
since Old Testament time that improperly cooked pork can pass
trichinosis from hogs to people. Although the vomiting and diarrhea
result from a worm and not a virus/bacteria, the relationship between
eating hogs and the possibility of contracting illness therefrom is
analogous to the Zoonotic dilemma: since the agricultural revolution,
we have made ourselves more and more dependent on a narrow range of
domesticated plants and animals and in so doing, have exposed
ourselves to a whole catalogue of hazards.
Moving from
nomadic, hunting/gathering to a sedentary, agricultural lifestyle
has, of course, vastly improved the availability of food but has also
resulted in burgeoning populations and the clumping of humanity into
villages, towns and, finally, metropolises. Smallpox once introduced
into a human population became epidemic very quickly where people
lived in close quarters; in the fifties, schools and churches shut
down during measles, mumps, scarlet fever outbreaks, for obvious
reasons.
The bigger you
build your ships, the harder it is to steer them onto a new course.
The history of living species being unable to adjust to changing
conditions in time to avoid annihilation is epic. It’s estimated by
some that the current rate of extinction of species is 10,000 times
the prehistoric average, possibly up to one extinction every 5
minutes.i
In historical terms, species like prairie songbirds, for instance,
have been unable to adjust their food and habitat needs in order to
survive the environmental changes humans have precipitated. The
introduction of zoonoses to the American continents left the Aztecs,
the Incas, the Mayans, the Cherokee and most other indigenous
inhabitants defenseless. The surviving remnant was obviously
weakened, often pock-marked by smallpox.
Human
ingenuity created the current, rapid explosion of change, and this on
a planet used only to the exceedingly slow adaptation of species a
la Darwin’s natural selection and survival of the fittest
principles. Whether or not human ingenuity is up to finding remedies
for complications caused by too-rapid change will be evident if and
when our history is written. With a population of 7,000,000,000+
individuals, we have created a massive challenge: “progress” has
resulted in an awfully big human-species ship; climate change,
super-bugs, resource depletion all represent massive, looming
icebergs.
The conquest
of the Americas was achieved by zoonoses and pillaging by greedy
“pirates,” erroneously portrayed in our histories as courageous
explorers and discoverers of lands . . . lands already settled,
ironically. Their actions can be excused in part on the basis of
ignorance; Henry Hudson, Christopher Columbus didn’t even know the
simple remedy for scurvy, much less the devastating power of the
world of microbes.
Ignorance can
no longer excuse our reluctance to do what we can to lessen the
effects of coming challenges or to prepare for their consequences. A
three minute read is enough to “set the scene” that will be our
climate iceberg.ii
Unlike the aboriginal peoples of the Americas, we have the means to
prevent and prepare; all we lack is the will.
Where I live,
mustering the will to get serious about the future is made difficult
because here on the prairies, our leadership is of the kind that
insists on using the only available water to irrigate a lucrative
potato patch while the house is burning. Unfortunately, I don’t
think any of Moe, Kenney or Palliser would appreciate the analogy.
Ihttp://www.theworldcounts.com/counters/degradation_and_destruction_of_ecosystems/species_extinction_facts
