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