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Today, we're going to talk about
Types of Agents.
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Now there are five
different types of agents:
biological, chemical, nutrient,
physical, and psychological.
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But before we talk about the
five different types of agents,
I want to make sure everyone
understands what an agent is.
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An agent is simply something
that causes harm to a human.
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So let's look at each in detail.
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Starting first with
biological agents.
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Biological agents include
bacteria, viruses,
fungi, protozoa,
worms, and insects.
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So for example, the influenza virus,
that's a biological agent.
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Next, we have chemical agents.
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And chemical agents come
in a variety of different forms.
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They can be liquid, solid, gas,
they can also be dust or fumes.
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So an example of a chemical
agent would be pesticides that we use
in our garden to keep the pests
away from eating our vegetables.
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Another example are
industrial chemical wastes.
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The next type of agent we
have here is nutrient agents.
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Now, a nutrient agent is simply
an essential dietary component
that could produce harm if it's taken
an excess or if there's not enough of it.
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So as an example,
Vitamin D deficiency can cause rickets.
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On the other hand, too much
vitamin A could be toxic to a human.
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Next, we have physical agents.
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And there's a few different
types of physical agents,
so let me walk you
through each of them.
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First,
we have mechanical physical agents.
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Now this could be
something like an automobile.
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It could also be something
as simple as a rug
that's on the floor that you
trip over when you're walking.
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Both are examples of
mechanical physical agents.
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Next,
we have a material physical agent.
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Here we see rocks
from a rock slide.
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Next,
we have atmospheric physical agents.
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A great example of that
is ultraviolet radiation.
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Then we have a geologic physical agent,
like an earthquake.
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And then finally,
we have genetic physical agents.
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And when we have anything
that's genetically transmitted
from person to person,
that's considered a physical agent.
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Now with physical agents,
the size, shape and force
of the physical agent influences
the degree of the harm to the host.
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So the larger the force, the bigger the
size, the more harm can be done to a host.
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And finally,
we have psychological agents.
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Now, psychological agents are really
anything that can cause you stress,
because we know that stress
negatively impacts our health.
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Now, it's important to remember
that stress is different for everyone.
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So it stresses me out may not
stress you on at all and vice versa.
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So it's important that we
understand the perceptions
of our patients and
our populations.
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So examples of
psychological agents could be
not feeling safe in your
neighborhood where you live.
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You could also have stress
related to work or school.
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So that anatomy exam
that you have coming up
could be a psychological
agent for you.
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Now,
understanding the type of agent
that's causing harm to a patient
or to a population is important.
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It allows us to develop an
intervention that's appropriate
that will stop that specific type
of agent from causing harm.
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So let's take a
look at an example.
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Here we have our chemical agent,
a pesticide.
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And if we know that
this chemical agent
is causing harm to an
individual or to a population,
then we can focus on eliminating
that chemical from the environment.
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This is a much better approach
than trying to address the harm
through say management of nutrients or
through physical agents in the environment.
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So again, understanding the
type of agent that's causing harm
to an individual or group
of people helps us address
that specific cause and
improve the health of the public.