Your body is being hijacked!
You are no longer in control.
Microscopic entities are flooding through
your systems and using your own cells against
you!
What is happening?
How do you stop these foreign invaders?
Well it depends.
Let’s take a step back and ask: what is
attacking you?
Is the pathogen a virus or bacteria?
This single question could be the difference
between life and death.
There are ways to kill bacteria that will
not kill a virus and vice versa.
So, let’s take a look at what the similarities
and differences are between a virus and a
bacteria.
Knowing the difference could save your life.
Both bacteria and viruses are microscopic,
meaning they are too small to see with the
naked eye.
They can enter your body through any opening,
but most often they enter through the nose
and mouth.
Are bacteria and viruses living things?
This is the first distinction between the
two pathogens that we will make.
Bacteria is most certainly alive.
In order to be classified as a living thing
something must have five traits.
The traits are: it’s made of cells, it grows
and reproduces, it responds to stimuli in
the environment, it can pass on genetic information,
and it must maintain homeostasis or an internal
balance.
If just one of these characteristics is missing,
it is not considered a living thing.
Bacteria meet all the requirements.
They are made of a single cell that divides
to reproduce and maintains homeostasis as
their environment changes.
Bacteria are likely the most diverse kingdom
of living things on the planet.
There are billions of different species of
bacteria.
Not only that, there are trillions of bacteria
in your body right now!
Bacteria in your body outnumber your own cells
by about ten to one!
Think about how crazy that is.
Just in sheer numbers there are more bacteria
in you than your own cells.
Biology is fascinating!
This brings up a really good point though.
If there are so many bacteria in you why aren’t
you dead, or at least sick all of the time?
Aren’t bacteria harmful to your body?
For anyone who has had food poisoning caused
by bacteria you wished you were dead at the
time.
Recently scientists have discovered that bacteria
play an important role in making up your body's
microbiome.
Bacteria are actually beneficial in many ways.
They can help you digest foods and keep your
skin healthy.
We have come to realize that bacteria actually
make your life better.
Without a healthy microbiome of bacteria in
your body you wouldn’t be able to eat certain
foods and you’d become sick more often.
We now know bacteria are living things.
They are single celled and have all of the
characteristics of life.
They are diverse and found everywhere around
the world.
Bacteria can be harmful, but they are also
beneficial to your body.
So are viruses the same way?
The short answer is no.
Viruses and bacteria have more differences
than similarities.
Let’s start with what seems like a basic
question.
Are viruses alive?
Well… it’s complicated.
Depending on who you ask in the scientific
community you will get a different answer.
Viruses are in a grey area between living
and nonliving things.
For example, they cannot reproduce without
hijacking the cells of a host.
This means that they don’t really have the
characteristic of reproduction.
All other living things can reproduce without
taking over another organism's cells and using
it for their own purposes.
Living things either find a mate and reproduce,
like humans, or split in two using a form
of asexual reproduction like bacteria.
Viruses can’t do either of these things.
Another characteristic of a living thing is
that they respond to their environment.
Viruses again are in a weird grey area where
they don’t so much respond to their environment,
as change it.
Viruses change the genetic code of cells to
suit their needs.
They can cause cells to make copies of themselves,
along with protein shells that carry them
to new cells to infect.
Viruses are tricky both in the way they use
our cells against us and identifying if they
are a living thing or not.
Bacteria on the other hand will respond to
their environment.
They will make more copies of themselves when
there is an abundance of resources or swap
their genetic code with other bacteria around
them if a beneficial trait arises that helps
the species survive.
Evolution by natural selection also is an
important concept when discussing living things.
All living things evolved from a species in
the past.
You, me, bacteria, we all evolved from an
organism that started life on this planet
billions of years ago.
Granted, you and bacteria went through many
different changes and evolutionary steps,
but humans and bacteria both evolved from
earlier species.
This is just how life works on our planet.
Viruses again blur the line here.
Viruses most definitely do change over time.
This is why you have to get a different flu
shot every year.
Although viruses are missing several characteristics
of a living thing they do seem to evolve.
And they seem to evolve fast.
Species evolve when a mutation in the DNA
occurs that gives an organism a new trait.
Mutations are random mistakes in the DNA,
so some are good, some are bad, and some don’t
have any effect on an organism's survival
at all.
But with viruses it would seem mutations happen
so often, and so rapidly, that a new form
of a virus can evolve almost overnight.
Are bacteria living things?
Yes they are.
Are viruses living things?
Ehh, they straddle the line between living
and nonliving.
Us humans like to make things clear cut and
binary.
Either yes or no.
Unfortunately, viruses don’t fit into one
category or another, which can scare and frustrate
us.
We talked about the benefits of bacteria.
But you may be wondering, do viruses give
us any benefits?
Or are they just little hijacking machines
that make us sick?
Well, one benefit of viruses is that weak
or less harmful ones can help boost your immune
system.
If you get the common cold, and it makes you
a little sick, your body may develop resistance
to a more malicious virus with a similar genetic
makeup.
In this case your body would be better able
to fight off the new virus thanks to the weaker
virus you got earlier in your life.
But let's talk about one of the coolest benefits
a virus can have for you.
Let’s talk about bacteriophages.
A bacteriophage is a virus that kills bacteria.
It targets a specific type of bacteria, infiltrates
it, takes over, and destroys it.
It’s pretty awesome when you think about
it.
Like little microscopic warfare happening
inside your body.
Imagine you have a harmful bacteria multiplying
away inside of you.
It’s making you sick and causing a lot of
distress.
Then a virus that has been lying dormant in
the mucus lining of your gastrointestinal
tract awakes from its slumber.
The viruses start attacking the harmful bacteria
by injecting them with their genetic code
and taking over.
Eventually the bacteriophages kill all the
harmful bacteria and are either evacuated
from your system or lie dormant again waiting
for their next victim.
That is pretty cool stuff if you ask us.
Bacteriophages are viruses that only kill
bacteria, so they pose no threat to your cells.
As of yet we know of no bacteria that kills
viruses, but there are countless different
viruses that can kill bacteria.
There is one last aspect of viruses that makes
them unique and different from bacteria.
We promised that biology is fascinating and
if we haven’t already delivered we are about
to.
When viruses infect us and hijack our cells
they can embed small chunks of their DNA into
our DNA.
Although this is rare it has been happening
for millions of years.
So, over time the viral DNA that has snuck
into human DNA has accumulated.
Your DNA right now is actually comprised of
around ten percent virus DNA.
Think about that.
One tenth of the genetic code that makes you
you, is actually virus DNA!
Like mutations, the chunks of viral DNA in
our genome were inserted randomly.
Some of it is harmful, such as viral DNA that
can cause cancer.
Other pieces of viral DNA have been beneficial
to us humans over our evolutionary history.
There is evidence that some of the virus DNA
in our genome helped in the development of
the human placenta.
Also, if you enjoy eating cereal, bread, or
any other food high in starch, you can thank
viruses for providing humans with the gene
that allows us to digest the complex sugar.
Viral DNA is responsible for creating starch
digesting enzymes in our pancreas cells.
Without virus DNA in our genome we would all
be on a starch free diet right now.
Bacteria are beneficial to humans in a lot
of ways.
Most especially in shaping our microbiome
and digestion of foods.
However, only viruses can claim the honor
of changing our DNA and influencing the course
of human evolution.
Have we mentioned how cool biology is yet?
Now let’s talk about the differences in
preventing or killing viruses and bacteria.
The first and most important distinction to
make when treating a pathogen is to identify
if it is a virus or a bacteria.
This is important because only certain medicines
work for certain types of pathogens.
Antibiotics are used to kill bacteria.
Antibiotics will only kill bacteria.
Hence the name anti meaning against and biotic
meaning living.
So antibiotics are only used to kill living
things, in this case bacteria.
Since viruses are complicated and don’t
reproduce using cellular division, antibiotics
have no effect on them.
It is important that you can distinguish between
viruses and bacteria to make informed decisions
about medication being recommended for an
illness.
We know bacteria are living things.
All living things are subject to the pressures
of natural selection.
When the environment of a bacteria changes,
let’s say an antibiotic is introduced, the
bacteria will be killed by it.
That is unless a random mutation allows one
bacteria to become resistant, and therefore,
able to fight off the antibiotic.
If this happens that species of bacteria will
keep on multiplying and could lead to severe
illness or death.
Antibiotic resistance is a process that is
driven by natural selection.
The bacteria can literally evolve in your
body to become resistant to antibiotics.
This is why it is so important to take the
correct dosage, for the correct amount of
time, when prescribed antibiotics by your
doctor.
Even if you stop showing symptoms you must
complete your antibiotic regimen, because
if you don’t, the bacteria you were trying
to kill are more likely to develop resistance
to that antibiotic.
We see this in certain parts of the world
with Tuberculosis.
Like we’ve said, living things tend to evolve
over time, otherwise that species would go
extinct.
Bacteria are no exception.
So if antibiotics only kill bacteria how do
we kill viruses?
There are two types of medicines that doctors
use.
The first is antiviral medication.
The drugs must be administered within a certain
time frame, and are only effective while the
medicine is in the patients system.
When you travel to areas of the world with
yellow fever, you can take an antiviral yellow
fever drug.
You have to take the pills as prescribed by
the doctor, before and during your trip, in
order for the drug to be effective.
The antiviral uses chemicals that kill the
virus, but only if those chemicals are in
your system when the virus infiltrates your
body.
Vaccines can be used to prevent or kill both
a virus or bacteria.
Every vaccine is different and made to kill
one type of pathogen.
Vaccines typically use a weakened or dead
form of the pathogen to activate the immune
system.
When the weakened or dead pathogen enters
your body your immune system identifies it
and makes antibodies that mark it for destruction.
After your immune system comes in contact
with the vaccine it will remember what the
virus or bacteria looked like, so if you ever
are infected with the actual pathogen your
body already has immunity to.
Then your immune system will do what it does
best and destroy the pathogen before it can
make you sick.
Vaccines work the same way against bacteria
and viruses.
We have learned a lot over the years about
viruses and bacteria.
We know they have some similarities, but are
different in many ways.
It is thanks to scientists and doctors that
we know so much, and can protect ourselves
from harmful pathogens like bacteria and viruses.
It is also thanks to scientists and doctors
that we understand the importance bacteria
and viruses can play in human evolution and
health.
What it comes down to is that biology is cool
and scientists are awesome.
That is why when scientists and doctors recommend
certain precautions to prevent a disease,
we should all listen.
If you are team virus then check out our video
Why Spanish Flu Killed Over 50 Million People
- Deadliest Plague in Modern History.
If you are team bacteria check out Why Would
a Scientist Inject Himself with 3.5 Million
Year Old Bacteria?
Just make sure you wash your hands with soap
and hot water for 20 seconds after finishing
the videos.
