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  • 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.

This is SARS CoV-2.

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COVID-19 Animation: What Happens If You Get Coronavirus?

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    ally.chang posted on 2020/04/16
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