Environmental Engineering Reference
In-Depth Information
Process
the multiple sources and reservoirs and biological mutations make the new diseases
more difficult to control. The new health threats lack the intentionality, targeting, and
guidance of the bioweapons of old. to be sure, smoking is controllable by the many
millions who engage in it, but the addictive properties of cigarettes and the influence
of the tobacco industry make it more difficult to stop. HIv/aIDS transmission is
similarly controllable by the many million carriers, but their sexual activity and
drug addictions make the proven defences of abstinence, faithfulness, and condoms
difficult to deploy. At the other end of the spectrum, human carriers or victims
could not readily control the SarS coronavirus, which spread through infectious
respiratory droplets by direct contact through eyes, nose, and mouth.
Pathway
the spread of these diseases similarly shows the emergence of a globalised microbial
world. a quarter of a century ago diseases once prevalent in the global economic
north, such as polio, malaria, and tuberculosis, had been conquered there. they
also promised to be eliminated in the South, as smallpox had been in 1979. the
North was thus largely left to deal with its self-inflicted diseases of affluence, such
as tobacco, obesity, cancer, and heart disease. and there was hope that vaccines,
like those discovered in the U.S. in 1961 to eliminate polio, could be deployed and
discovered in the South as well. but HIv/aIDS, although discovered in the north
in 1981, has spread throughout the South where it originated largely unchecked,
with 60 percent of the world's infected population living in southern africa alone.
tobacco use is being contained in the north but is similarly spreading throughout
the South.
At the same time, there has arisen a reverse flow from South to North. That
SARS started in China and flowed into north america destroyed the assumption that
communicable disease had largely become a problem only for the underdeveloped
South. and avian influenza is now also spreading relentlessly from South to North.
Most important has been the advent of simultaneity on a fully global scale.
Disease once spread slowly to a few neighbouring countries in a step-by-step linear
advance. but SarS erupted almost at the same time in countries as far apart as
china and canada. Avian influenza could spread in similar fashion as well. airline
routes and bird flyways can immediately take a disease from almost anywhere to
almost anywhere. as adam Kamradt-Scott notes, in the case of SarS never before
had so many countries been afflicted at same time. The physical health challenge has
now become a simultaneous global one.
Causes
there are many causes of these new cadences, with many being featured on several
authors' lists. at the core lies the biology of microbial mutation and transfer. In
