This is SARS CoV-2.
It belongs to the family of coronaviruses,
named for crownlike spikes
on their surfaces.
SARS CoV-2 can cause COVID-19,
a contagious viral infection
that attacks primarily your throat and lungs.
What actually happens in your body
when you contract the coronavirus?
What exactly causes your body
to develop pneumonia?
And how would a vaccine work?
The coronavirus must infect living cells
in order to reproduce.
Let's have a closer look.
Inside the virus,
genetic material contains the information
to make more copies of itself.
A protein shell provides a hard protective
enclosure for the genetic material
as the virus travels between
the people it infects.
An outer envelope allows the virus
to infect cells by merging with
the cell's outer membrane.
Projecting from the envelope are
spikes of protein molecules.
Both a typical influenza virus and
the new coronavirus use their spikes
like a key to get inside a cell in your body,
where it takes over its internal machinery,
repurposing it to build the components
of new viruses.
When an infected person talks,
coughs or sneezes,
droplets carrying the virus may land
in your mouth or nose
and then move into your lungs.
Once inside your body,
the virus comes into contact
with cells in your throat, nose or lungs.
One spike on the virus
inserts into a receptor molecule
on your healthy cell membrane
like a key in a lock.
This action allows the virus
to get inside your cell.
A typical flu virus would travel
inside a sack
made from your cell membrane
to your cell’s nucleus
that where your cell houses
all its genetic material.
The coronavirus, on the other hand,
doesn’t need to enter the host cell nucleus.
It can directly access parts of the host cell,
called Ribosomes.
Ribosomes use genetic information
from the virus to make viral proteins,
such as the spikes on the virus’ surface.
A packaging structure in your cell
then carries the spikes in vesicles,
which merge with your cell's
outer layer, the cell membrane.
All the parts needed to create a new virus
gather just beneath your cell's membrane.
Then a new virus begins to butt off
from the cell's membrane.
For this, we’ll have to look into your lungs.
Each lung has separate sections,
called lobes.
Normally, as you breathe, air moves freely
through your trachea, or windpipe,
then through large tubes, called bronchi,
through smaller tubes, called bronchioles,
and finally into tiny sacs, called alveoli.
Your airways and alveoli
are flexible and springy.
When you breathe in,
each air sac inflates like a small balloon.
And when you exhale, the sacs deflate.
Small blood vessels, called capillaries,
surround your alveoli.
Oxygen from the air you breathe
passes into your capillaries,
then carbon dioxide from your body
passes out of your capillaries
into your alveoli so that your lungs
can get rid of it when you exhale.
Your airways catch most germs
in the mucus that lines your trachea,
bronchi, and bronchioles.
In a healthy body,
hair-like cilia lining the tubes
constantly push the mucus and germs
out of your airways,
where you may expel them by coughing.
Normally, cells of your immune system
attack viruses and germs that
make it past your mucus and cilia
and enter your alveoli.
However,
if your immune system is weakened
like in the case of a coronavirus infection,
the virus can overwhelm your immune cells
and your bronchioles and alveoli
become inflamed
your immune system attacks
the multiplying viruses.
The inflammation can cause
your alveoli to fill with fluid,
making it difficult for your body
to get the oxygen it needs.
You could develop lobar pneumonia,
where one lobe of your lungs is affected,
or you could have bronchopneumonia
that affects many areas of both lungs.
Pneumonia may cause...
difficulty breathing
chest pain
coughing
fever and chills
confusion
headache
muscle pain
and fatigue.
It can also lead to
more serious complications:
respiratory failure occurs when
your breathing becomes so difficult
that you need a machine called
a ventilator to help you breathe.
These are the machines that save lives
and medical device companies currently
ramp up production for.
Whether you would develop
these symptoms depends on
a lot of factors, such as
your age and whether you
already have an existing condition.
While all this all sounds scary,
the push to develop a coronavirus vaccine
is moving at high speed.
Studies of other coronaviruses
lead most researchers to assume that
people who have recovered from
a SARS-CoV-2 infection could be protected
from reinfection for a period of time.
But that assumption needs to be backed
by empirical evidence and
some studies suggest otherwise.
There are several different approaches
for a potential vaccine
against the coronavirus.
The basic idea is that
you would get a shot that contains
faint versions of the virus.
The vaccine would expose your body
to the virus that is too weak
to cause infection but just strong enough
to stimulate an immune response.
Within a few weeks,
cells in your immune system would
make markers called antibodies,
which would be specific for
only the coronavirus or specifically
its spike protein.
Antibodies then attach to the virus and
prevent it from attaching to your cells.
Your immune system then responds
to signals from the antibodies
by consuming and destroying
the clumps of viruses.
If you then catch the real virus
at a later stage,
your body would recognize and destroy it.
In other words,
your immune system is now primed.
Collecting evidence on
whether this will be possible,
safe and effective
is part of what’s taking researchers
so long to develop a vaccine.
It is a race against time
to develop a vaccine amid a pandemic.
Each step in vaccine development
usually takes months if not years.
An Ebola vaccine broke records
by being ready in five years.
The hope here is
to develop one for the new coronavirus
in a record-breaking 12 to 18 months.
While all this will take time,
stay home if you can
to protect the most vulnerable
and don’t forget to wash your hands
for at least 20 seconds and
as often as possible.
What would happen if you didn't do that
for an entire year?
Well, that’s a story for another WHAT IF.