00:01
So let's talk a bit about zoonoses.
00:04
Many infectious epidemics and pandemics are
caused by this thing we call zoonotic diseases.
00:10
We call them that because they
start in animals, non-human animals
and they jump into human beings
and usually they're linked
to some kind of mutation.
00:19
Gene sharing that viruses and bacteria
do that allows them to find the plasticity
to infect human beings.
00:27
And when they do so, they can be
quite, quite virulent and quite dangerous.
00:31
So globally, we're always on the lookout for a
new potentially pandemic quality zoonotic strains,
Zoonoses are caused by
a range of infectious agents
including of course viruses,
bacteria, fungi and parasites.
00:50
So here's some notable zoonoses.
00:53
Of course COVID-19.
00:55
It started out as an infection
in bats and made it to humans
possibly being amplified by an
intermediary species of pangolin.
01:04
And we think that it was able to do
this because it was in close proximity to
different kinds of animals and human beings
by virtue of being in the wet markets of East Asia.
01:15
So close association with many animals
through domestication in agriculture,
we think is one of the reasons that zoonoses happen.
01:24
It allows these diseases to share DNA
with other diseases and other animals.
01:32
HIV is thought to have started in other
non-human primate and made its way into humans.
01:39
Malaria of course is associated with mosquitoes.
01:42
Ebola, we think its natural reservoir
is bats, and somewhere along the line,
it moved from bats in human beings.
01:51
Salmonella famously is in a variety
of foods that we eat, including turtles.
01:56
So those who keep live turtles
or eat poorly-cooked turtle flesh
are risking salmonella poisoning.
02:05
Bird flu and swine flu or named that
way because they are zoonotic diseases
that begin in birds and pigs.
02:16
Anthrax comes from the
droppings of domesticated livestock.
02:22
And of course, the bubonic
plague, Yersinia pestis.
02:27
Its natural reservoir is
probably some kind of rodent.
02:31
We know it has, during its life
cycle, it's in fleas at some point.
02:36
It's always being investigated further,
but definitely has a close association with
non-human animals.
02:44
Lyme disease is tick-borne.
02:47
Mostly the ticks feed on other animals,
but sometimes they jump on people.
02:51
When they do that, the pathogen
jumps into us.
02:56
Toxoplasmosis is associated with cats.
03:00
It's one of the reason that pregnant women
are often advised to stay away from cats
because they can infect them with
toxoplasmosis and that can
have a deleterious outcome to the pregnancy.
03:11
Histoplasmosis is another such fungal disease.
03:16
And Giardia, also associated with
a variety of domesticated animals.
03:24
As I mentioned, histoplasmosis,
often associated with bird droppings.