How the melting glaciers can cause the next epidemic
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a warming planet greater temperature
variability new pathogens like covet 19
what does this mean for us as humans
why is it absolutely essential that we
slow down climate change
friends we live in an ocean of bacteria
viruses and fungal pathogens in fact
like fish living in water we live in a
sea of microbes they make life possible
for us on the planet they produce half
the oxygen that we breathe they take
care of breaking down our waste and they
enable the very life that makes us
possible however some of them also cause
disease as we have seen most recently
with covid
a virus that normally lives in bats has
managed to find its way into humans
where it is able to survive and thrive
and when this happens and it’s a process
we call zoanosis then we face diseases
we’ve never faced before
climate change makes us possible in at
least three ways that we know of
first our very environment is changing
and putting us in close contact with
hidden pathogens that we have never
encountered before
a few years ago
anthrax killed a 12 year old boy in the
yamal peninsula in a remote part of
siberia
another 20 people in this area were
infected with anthrax and another 100
suspected cases were hospitalized
but very importantly more than 2 300
reindeer in the area died from the
infection
why did this happen
thawing permafrost which is permanently
frozen layers of soil released
previously immobile spores of anthrax
into the nearby water and soil
and then into the food supply
there had been no anthrax outbreak in
this region in the previous 75 years
the siberian permafrost which is about a
million years old is home to billions of
funguses bacteria and viruses that are
slowly emerging with the melting of the
permafrost when these pathogens
eventually jump to animals and then to
us humans we are at great risk
second the increase in temperature is
selecting for pathogens that are able to
adapt to our temperatures many funguses
would not normally survive in the human
body because our bodies are just too
warm for them but some of them are now
adapting to the warmer ambient
temperature due to climate change
and as you can see in this graphic these
newly adapted fungi move to birds and
finally to humans where they cause
terrible diseases
a recent example is a fungus called
candida auris this fungus was first
described in 2009 after it was isolated
from the ear canal of a 70 year old
japanese woman in tokyo
thirty to sixty percent of people with
canada oris infections have died i
repeat thirty to sixty percent of people
with canada oris infections have died
to date there have been fewer than 10
000 cases globally but as we saw with
cases of black fungus in the aftermath
of covid fungal pathogens are always
waiting to attack patients with weakened
immune systems
third is the combination of climate
change and drug resistance as we use
more antibiotics in humans in animals to
help them grow fatter faster and even on
fruit trees we’re helping to make
pathogens more resistant to the drugs
that we typically use to treat these
bacterial infections with now take the
example of the fungus canada orders
which i just spoke about canada happens
to be resistant to the most common
category of antifungals called azoles
and that’s probably because we have
extensively used azoles as fungicides in
agriculture
research by my team at princeton
university shows that gram-negative
bacteria a particularly lethal category
of bacteria and those that are drug
resistant are more likely to thrive in
warmer temperatures
specifically every one percent increase
in temperature results in a two percent
increase in the frequency of resistant
bacteria
so as the climate changes we face even
more lethal pathogens that we can no
longer treat
even today 700 000 deaths are caused
each year mostly in developing countries
because of these drug resistant bacteria
and nearly all of the disease-causing
bacteria that we encounter have become
drug resistant
and as this graphic shows the number of
enzymes that bacteria are now able to
produce to disable antibiotics that we
know of was just 102 about 50 years ago
today there are over a thousand of these
enzymes that we know of
so where does this leave us climate
change is already causing rising oceans
hurricanes droughts floods and heat
waves at a scale we have not seen before
climate variability is a challenge
but at dimensions we don’t even
understand yet
and undoubtedly as with covid we will
discover more
but the sad truth is that the people who
are most affected are the poor who also
happen to be the most vulnerable to
infections
the very people who did not contribute
to climate change to begin with are the
most affected
we’re simply not ready for climate
change
if we want to avoid a repeat of the past
two years of covid we simply have to
understand that we humans are vulnerable
to pathogens we need more research we
need to be proactive with surveillance
to find pathogens before they find us
but we also need to slow down climate
change
my friends we have no choice
and you hold the key
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you