What makes Ebola so dangerous?
How can a virus overwhelm the very complex
defense system of the body so quickly
and so effectively?
Let's take a look at what Ebola does.
(Theme music)
Ebola is a virus.
A virus is a very small thing.
A bit of RNA or DNA
and a few proteins
and a hull.
It has no ability to do anything
by itself whatsoever,
and can only survive and proliferate by infecting cells.
To avoid this we have the immune system.
The immune system is super complex
so we develop a visual system
that makes it easy to understand.
So it looks like this:
Let's concentrate on the part that is critical to understanding Ebola
and ignore the rest.
So usually dendritic cells will activate the army
of anti-virus cells, support cells
and anti-body factories
that work together with the guard cells
wipe out the infection in a matter of days.
But when Ebola strikes, it directly
attacks the immune system.
Some of the first cells it takes over are
the dendritic cells, the brains of
the immune system.
The Ebola virus enters a dendritic cell by
binding into receptors for cell transport.
Once it is inside, it dissolves its outer hull and releases
its genetic material, nucleoproteins and enzymes.
In a nutshell it takes over the cell,
disables the cells protective mechanisms and
reprograms it.
The cell now becomes a virus production machine
and uses its resources to build Ebola viruses.
Once the cell is saturated, it dissolves the cell membrane
and millions of viruses are released into the tissue.
The virus not only prevents the dendritic cells
from activating the specialized and anti-virus forces,
it manipulates them into sending signal proteins
that tricks specialized cells
into ending their own life's prematurely.
So the immune system is seriously disrupted
and unable to react.
When the virus rapidly multiplies, we're talking billions,
there are cells that should deal with infected cells,
the natural killer cells, but they also get infected
and just die before they can prevent
the disease from spreading.
At the same time Ebola infects
the guard cells of the body
macrophages and monocytes,
not only managing to circumvent their defenses,
it also manipulates some to signal to
the cells make up the blood vessels
telling into release fluid into the body
Usually this makes sense, but in this case
it just causes mayhem.
All of the body's neutrophils are activated
awaken by the virus and the macrophages signals
then are not very effective against viruses and
should not be involve in this fight and
begin to do lots of stuffs they shouldn't do.
The neutrophils signals to the blood vessels to
release more fluid causing internal bleeding.
Another area of the body Ebola
attacks is the liver. The virus finds it
very easy to enter the liver and
it quickly starts killing loads of liver cells
and causing organ failure and more internal bleeding.
And all those things are going on at the same time.
As the virus spreads, it's like nukes exploding every where.
One incident of this in one region will be problem enough
But now is starting to happen everywhere at once.
All the mechanisms of the immune system have evolve to
handle infections work against you.
And the virus continues to spread and spread.
And finally begins to infect more and more body cells
while the body desperately struggles to stay alive.
In a desperate last effort to turn the tide
the immune system launches a cytokine storm.
A cytokine storm is an S.O.S signal
that causes the immune system to launch all of its weapons,
all at once in a desperate kamikaze attack.
This hurts the virus but leaves behind tons of collateral damage,
Especially in the blood vessels.
Paradoxically the healthier the immune system,
the more damage it can do to itself
More and more fluid leaves the blood stream.
Blood pours after every opening of the body.
You become seriously dehydrated
that just not now blood left to supply the organs with oxygen
and cells begin to die. If you reach this point
the chance of you dying is very high.
Currently six out of ten infected die from Ebola.
Wow! Ok. Ebola is nasty. So it’s time to panic, right?
No, not even close.
The severity of Ebola gets paper sold and
YouTube videos shared so everybody is talking about Ebola.
But currently the only way to get infected by Ebola
is to come into contact with the body fluids
of a person who shows symptoms
Or from infected bat. So just don’t do that.
Ebola has killed 5,000 people since June 2014.
The common flu kills up to 500,000 people each year.
Malaria causes up to one million each year.
3,000 people every single day. Ten children since this video started.
So even if Ebola is terrible and scary,
don’t let yourself be scared. The most infectious thing about Ebola
is the media hype around it.
You could learn a bit more about the immune system though
Transcription made by Miriam Delgado
Subtitles by the Amara .org community
Revised by: Ace Ervite