How coronavirus kills human | How coronavirus kills: Acute Respiratory distress syndrome
How does the coronavirus causes death?
How Does The COVID-19 Coronavirus Kill?
So exactly What Does the Coronavirus Do to the Body ?
what actually happens to your body when it is infected by the coronavirus?
•For
most patients, COVID-19 begins and ends in their lungs, because like the flu, coronaviruses are respiratory
diseases.
•
It can affect your upper respiratory tract that is (sinuses, nose, and throat)
or
•lower
respiratory tract that is windpipe and lungs.
•windpipe
also called trachea, it divides into two
main bronchi.
together, the trachea and the two primary bronchi are called the bronchial
tree. And At the end of the bronchial
tree lie the alveoli.
•They
spread typically when an infected person coughs or sneezes, spraying droplets
that can transmit the virus to anyone in close contact
•
people nearby can take in through their nose, mouth or eyes.
•The
viral particles in these droplets travel quickly to the back of your nasal
passages and to the mucous membranes in the back of your throat, attaching to a
particular receptor in cells, beginning there.
•Coronavirus particles have
spiked proteins sticking out from their surfaces, and these spikes hook onto
cell membranes, allowing the virus’s genetic material to enter the human cell.
•That
genetic material proceeds to “hijack the metabolism of the cell and say, ‘Don’t
do your usual job. Your job now is to help me multiply and make the virus. From
here the phases of damage begins. Lets understand shortly.
•disease
typically attacked the lungs in three phases:
•1.
viral replication,
•2.
immune hyper-reactivity,
•3.
and pulmonary destruction.
•Not
all patients went through all three phases—in fact only 19 percent of , COVID-19 patients suffered severe or
critical.
Phase
no 1 viral replication
•viral
replication means the formation or
multiplication of viruses during the infection process in the target host
cells. Host cells means a cell that is infected by a virus or another type of
microorganism.
•In the early days of
an infection, the novel coronavirus rapidly invades
human lung cells. Those lung cells come in two classes:
•ones that make mucus
and
•ones with hair-like
batons called cilia.
•Mucus, though gross
when outside the body, helps protect lung tissue from pathogens and make sure
your breathing organ doesn’t dry out.
•The cilia cells beat
around the mucus, clearing out debris like pollen or viruses.
•SARS or Severe acute
respiratory syndrome coronavirus, infect and kill that cilia cells.
•which then sloughed
off and filled patients’ airways with debris and fluids,
•that’s
because of the
earliest studies on COVID-19 have shown that many patients develop pneumonia in
both lungs, accompanied by symptoms like shortness of breath.
•The
coronavirus damages both the
wall and lining cells of the alveoli as well as the capillaries.
- alveoli are the tiny air sacs within the lungs where the
exchange of oxygen and carbon dioxide takes place.
- The debris that
accumulates because of all of that damage lines.
•
The damage to capillaries also causes them to leak plasma proteins that add to
the wall’s thickness.
•Normally
alveoli have very thin membranes to facilitate gas exchange.
•But“Eventually,
the wall of the alveolus gets thicker than it should be,”
•
“The thicker this wall gets, the harder it is to transfer oxygen, the more you
feel short of breath,
Phase no. 2 immune hyper-reactivity
•That’s when phase two
and the immune system kicks in. Aroused by the presence of a viral invader, our
bodies step up to fight the disease by flooding the lungs with immune cells to
clear away the damage and repair the lung tissue.
•When working
properly, this inflammatory process is tightly regulated and confined only to
infected areas. But sometimes your immune system goes haywire and those cells
kill anything in their way, including your healthy tissue.
•“So
you get more damage instead of less from the immune response. Even more debris
clogs up the lungs, and pneumonia worsens.
Phase no. 3 pulmonary destruction
•During
the third phase, lung damage continues to build—which can result in respiratory
failure.
•Even
if death doesn’t occur, some patients survive with permanent lung damage.
According to the WHO, SARS punched holes in the lungs, giving them “a
honeycomb-like appearance”—and these lesions are present in those afflicted
by novel coronavirus, too.
•These
holes are likely created by the immune system’s hyperactive response, which
creates scars that both protect and stiffen the lungs.
•When
that occurs, patients often have to be put on ventilators to assist their
breathing.
•Meanwhile,
inflammation also makes the membranes between the air sacs and blood vessels
more permeable, which can fill the lungs with fluid and affect their ability to
oxygenate blood.
•“In
severe cases, you basically flood your lungs and you can’t breathe,” “That’s
how people are dying.”
•Sepsis is a common cause of death from coronavirus
•Sepsis
is a life-threatening organ dysfunction caused by the body's immune system
overreacting in response to an infection. This overactive, toxic response
can lead to tissue damage, multiple organ failure and death.
Death rate is variable according to the level of severity
•Generally there are 3 levels
1. mild disease-
At this early stage, you will not be sick and some people may never develop symptoms.
• About 80% of
people who get Covid-19 experience a mild case – about as serious as a regular
cold – and recover without needing any special treatment.
symptoms like fever
and cough are treated with bed rest, plenty of fluids and paracetamol. You won't need
specialist hospital care.
•This stage lasts
about a week - at which point most recover because their immune system has
fought off the virus.
2. Severe disease
•If the disease
progresses it will be due to the immune system overreacting to the virus.
•"The virus is
triggering an imbalance in the immune response, there's too much inflammation
•Too much inflammation
can cause collateral damage throughout the body.
•Inflammation
of the lungs is called pneumonia.
•in pneumonia the tiny
sacs start to fill with water and can eventually cause shortness of breath and
difficulty breathing.
•Some people will need
a ventilator to help them breathe.
•This stage is thought
to affect around 14% of people,
3. The third Level is Critical disease
•It is estimated
around 6% of cases become critically ill.
•By this point the body is starting to fail and there is a real chance of death.
•The problem is the immune system is now spiralling out of control and
causing damage throughout the body.
•It can lead to septic the shock when the blood pressure drops to dangerously low levels and organs stop
working properly or fail completely.
•Acute respiratory
distress syndrome or ARDS caused by widespread inflammation in the lungs stops
the body getting enough oxygen it needs to survive. It can stop the kidneys
from cleaning the blood and damage the lining of your intestines.
•"The virus sets
up such a huge degree of inflammation that you succumb... it becomes
multi-organ failure.
•Death rates also
depend on a range of factors like your age and general health and the care you
can access.
•The
elderly and the unwell or those who have low immunity are more likely to die,
if they contract coronavirus.
•Current
estimates from Imperial College London are that the death rate is almost 10
times higher than average for those over 80 years of age, and much lower for
those under 40 years of age.
