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  • It’s March 2020 and the world has been battling a new coronavirus outbreak for months.

  • Since the first case originated in late 2019 in the city of Wuhan, China,

  • the virus has made its way across the globe,

  • causing economic decline, quarantines, and death.

  • The World Health Organization has officially raised the global alert to the highest possible level.

  • This novel coronavirus is a cause for concern because of how little we know about it

  • and how quickly it’s spreading.

  • What is different with this virus, which is both good and bad, is that it's much less severe than SARs.

  • But it also means that a lot of people remain undetected because it looks a bit like a normal common cold.

  • They don't develop very severe symptoms,

  • and by the looks of it, people are already shedding the virus while they're still quite healthy.

  • Now, firstly, the novel coronavirus has been named SARS-Cov2,

  • while the disease it causes is called COVID-19—short for coronavirus disease 2019.

  • In just a few months, this coronavirus has caused over 97,000 cases of confirmed infection

  • and has claimed over 3,000 lives, globally.

  • These numbers continue to increase as it makes its way across the world and as we get better at identifying it.

  • Now, as of March 3rd 2020, the WHO estimates that the death rate from COVID-19

  • is around a preliminary 3.4%, which is higher than the flu.

  • But SARS-Cov2 has so far infected less than the flu has at its highest season,

  • and estimations between the two will most likely continue to change as time moves on.

  • No matter the comparison though, it’s still evident that lives are at stake from COVID-19.

  • Which is why scientists are working rigorously on understanding its transmission,

  • behavior, and how they can stop it.

  • Since this viruses global debut, what have we learned about it and how fearful should we be?

  • Coronaviruses are named for their structural elements,

  • so they have this very prominent protein on their surface

  • which is called a spike protein.

  • We see them very prominently on the outer ringand that looks a bit like a crown, or like the sun's corona

  • when we have a solar eclipse.

  • And that gives them their name.

  • In most cases, coronaviruses are respiratory RNA viruses that infect animals,

  • such as bats, cats, and birds.

  • But when they make the jump to humans, these viruses are known as zoonotic.

  • There are seven known coronaviruses that will infect humans,

  • causing diseases like the ones were familiar with: COVID-19, SARS, and MERS.

  • SARS and MERS are previous outbreaks from the last few decades.

  • In 2002, there was SARS, meaning Severe Acute Respiratory Syndrome.

  • And in 2012, there was MERS, meaning Middle East Respiratory Syndrome.

  • They each took less than 1,000 lives.

  • But both are known to cause a severe case of pneumonia and lung injury,

  • and death rates from these infections are higher than COVID-19: from 11% to more than 30%.

  • So, what we see with this virus is that it's definitely much milder than SARs, within the known SARS,

  • within the known SARS cases.

  • What contributes to the virus being so much milder than SARs are many, many contributing factors

  • and we definitely don't know the details of it yet from a virus perspective,

  • but it appears to be where the virus infects.

  • So more lungs alone rather than what we call systemic disease,

  • when the virus attacks our internal organsour intestines as well

  • so that makes the virus much milder than what we saw with SARS.

  • In fact, mortality rates from COVID-19 vary on the age and previous health of the patient.

  • Since it’s usually not the coronavirus itself, but how your immune system responds.

  • So, for any virus to cause a human disease, they need to get into human cells.

  • Different viruses like to grow in different cells of the body.

  • This new coronavirus likes to grow in the lung cells.

  • When they get into a cell, they require a surface receptor.

  • So, the spike protein, that very prominent protein that we see,

  • is basically the key-lock interaction that tells the cell to take up this virus so that it can eventually

  • hijack the cellular machinery and use it to make more of itself.

  • This virus uses a protein called ACE2, as a receptor.

  • The virus has to bind with the receptor to be able to get inside the cells.

  • ACE2 is found throughout the respiratory tract and SARS-Cov2 seems to have a liking to cells

  • in both the upper and lower part of our respiratory system.

  • The lower respiratory tract includes the trachea, bronchi, bronchioles, and alveoli.

  • The upper respiratory tract includes the nostrils, nasal cavity, mouth, throat, and voice box.

  • When we have an infection in our lungs, then we have a lot of immune cells that come to help clear that virus,

  • but at the same time, that's liquid and cells which both block that thin layer of cells from taking up oxygen.

  • And then obviously we want a physical barrier, which is mucus,

  • to kind of wash out the virus. And that makes us cough, that brings us respiratory problems.

  • Because of that damage, sometimes there is an accumulation of fluid in that part of the lung,

  • and that is what we call pneumonia.

  • Most of the patients that have died because of this coronavirus, have died because of pneumonia.

  • Of course, like we said before, there are other factors that can make this a lethal disease.

  • I would also like to emphasize that it seems that most of the people that have died

  • because of this new coronavirus, so far, were either elderly, or they had an underlying disease condition.

  • It seems that if your immune system is compromised for any reason,

  • then you have a higher chance of getting a severe infection.

  • To understand the origin of SARS-Cov-2 and its transmission,

  • scientists sampled its genomes in 53 individuals back in January 2020.

  • They converted the viruses nearly 29,000 nucleotides bases into workable DNA,

  • which was shared with labs across the globe.

  • Based on that DNA, they were able to distinguish that the virus was roughly 96.2% similar to a bat coronavirus

  • and about 79.5% was similar to the coronavirus that causes SARS.

  • So SARS-Cov-2 seems to have started in bats,

  • but there needs to be a link between how the coronavirus lives in bats

  • and to the slightly different kind of coronavirus found in humans.

  • And that link is still unknown.

  • Despite early theories that the outbreak originated in a seafood market in Wuhan,

  • there's evidence that may not be the case.

  • So, what happens next?

  • As of February 2020, teams in China and the U.S. National Institute of Allergy and Infectious Diseases

  • are already testing an antiviral drug called Remdesivir to combat the spread.

  • Created by a U.S.-based biotech company named Gilead,

  • the experimental drug was shown to block the activity of a protein that helps coronaviruses

  • make copies of themselves.

  • Lab tests showed promise in animal models for SARS and MERS,

  • and the treatment was also successful when used on a U.S. patient with COVID-19.

  • While the FDA hasn’t approved this drug,

  • clinical trials have started with 270 patients at Beijing's China-Japan Friendship Hospital,

  • roughly 1,000 patients spread throughout Asia,

  • and a clinical trial in the U.S. that administer similar treatment.

  • I think a lot of future efforts are going to be focusing on drug development,

  • because it's very clear right now that these viruses might continue to jump from animals to humans,

  • so we should definitely be ready for another outbreak in future,

  • and antiviral drug development and vaccine development are the way to go.

  • There's so much to discuss when it comes to COVID-19.

  • If there’s another aspect of it that you want to see us cover,

  • please let us know in the comments below, and make sure to subscribe to Seeker

  • to see how we follow this news.

  • Thanks for watching, go wash those hands, and I’ll see you next time.

It’s March 2020 and the world has been battling a new coronavirus outbreak for months.

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