Hello and welcome to a special edition
of Immunology Wars I'solo'ation - COVID-19
COVID -19 is an infection caused by SARS
CoV2 or severe acute respiratory syndrome coronavirus 2 and is a disease that has
spread across the globe causing a
pandemic. The virus is mainly spread
between people via close contact often
from small droplets created during
coughing, sneezing and even just talking.
A majority of these droplets will fall
to the ground but the virus is able to
survive on hard surfaces and has shown
to be alive even after 72 hours. If
another person touches that surface and
picks up the virus and then touches
their nose or mouth they are at risk of
infection.
We can think of this as Supreme
Chancellor Palpatine, who represents the
virus, using his position in the Senate to
influence all the other Republic systems
spreading his own ultimate goals.
Coronavirus is thought  to be a zootropic
virus which means that it's crossed
between species. You can think of this as
Chewbacca as a Wookie getting a viral
infection and then being able to pass
that disease on to Han Solo as a human
host. There are many examples of zootropic
diseases, including some strains of flu
that originated in birds or pigs and
coronavirus-2 is thought to have
originated in bats. Signs and symptoms of mild COVID-19 infection are similar to
flu; they include a persistent cough,
fever, fatigue, and shortness of breath.
In more severe cases difficulty breathing
and the development of pneumonia will
require hospital treatment. So what is
actually happening at the immunological
level when someone gets COVID-19? Well
the virus enters host cells mainly the
alveoli of the lungs by binding to a
special enzyme called angiotensin
converting enzyme 2 or ACE2.
This enzyme normally helps control blood
pressure but in COVID-19 the virus is
able to bind to it and use it as a
mechanism to enter the host cell. This is
Palpatine influencing all the Republic
systems allowing him to spread!
Viruses need a living host cell in order
to replicate and cause further infection.
These cells are then able to present part of
the virus on their surface and alert the
immune system to their presence.
Inflammation results in vasodilation,
allowing recruitment of cells of the
immune systems to the lungs, in
particular resident macrophages,
represented here by Chewbacca and
natural killer cells represented by Jedi
Master Mace Windu. In some cases these cells are sufficient to contain the virus by
destroying cells that the virus has
managed to infect,
whilst also allowing an adaptive immune
response to develop. We can think of this
adaptive immune response as Luke
Skywalker training a specific cohort of
clones, which represents our T-lymphocytes, all of which are aimed to
attack the threat. Or X-Wing pilots, who
are antibodies being briefed about the
specific weaknesses of the virus by
Admiral Ackbar,
who is our B-lymphocyte. This adaptive
immune response is often sufficient to
eradicate the virus and individuals in
which it is successful
may only percent with mild symptoms of
COVID-19. However, in more severe cases
COVID-19 can cause damage to lung cells
and this causes the immune system to
respond to this damage by flooding the
areas with neutrophils represented here
by Han Solo, the recruitment of monocytes from the circulation shown here by
Chewbacca and T-lymphocytes,
which are the Clone Troopers and these
Clone Troopers represent cytotoxic
T-cells, which are designed to eradicate
cells. All these cells are
pro-inflammatory and they can release
large amounts of cytokines. These are
chemicals represented here by C-3PO,
which are messengers of the immune
system and can result in systemic hyper
inflammation. Essentially what is
happening here is that the cells that were
once helping protect our body
are now causing damage to the very
thing they are meant to protect. In
essence, Palpatine has executed Order 66
and the cells of the immune system have
turned on the body, just as the clones
turned on the Jedi. This over release of
cytokines is known as a cytokine storm
and can be a very serious condition,
contributing to the damage seen in the
lungs of patients with severe COVID-19 infections. This can result in the
potentially life-threatening acute 
respiratory distress syndrome. Other
changes include alterations in blood
pressure,
lack of oxygen reaching tissues and
organs and it can ultimately lead to
organ failure. There's currently no
treatment or vaccine for COVID-19, although
researchers are working hard to
develop one and it is possible that
existing medications might be able to be
repurposed to help fight this disease.
However, the most effective way to combat
COVID-19 remains preventing its spread, so
practice social distancing, wash your
hands more frequently and try to avoid
touching your face with your hands will
all help prevent the future spread of
this pandemic. This has been a special
episode of Immunology Wars based on
the current situation that we find
ourselves in. In our next episode
The Rogue One we will be looking at the
immune response to cancer. I hope you'll
be able to join us then for the next
episode of Immunology Wars
