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Practice English Speaking&Listening with: What We Know About the New Coronavirus

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[ intro ]

On December 29th, 2019,

four individuals showed up at a hospital in Wuhan, China.

All had pneumonia and worked

in a particular seafood and live animal market

which was enough of a coincidence to pique the interest of local health experts.

Two days later,

Chinese authorities alerted the World Health Organization of a new,

potentially serious respiratory virus.

And youve probably heard about it by now.

Heres the thing, though:

The emergence of a new disease

can be a really uncertain time,

with a lot of unknowns and misinformation.

So heres a hopefully-helpful breakdown

of what we do know about this new virus.

And why theres no need to panic.

First off,

while you might hear some people calling this theWuhan virus

because that's where it was first noticed

scientists no longer name diseases after people, places, or animals.

The virus doesn't actually have a formal name yet,

but youll see experts referring to it as 2019-nCoV

which is simply shorthand for 2019 novel coronavirus.

As that name implies, its a type of coronavirus.

Thats a large family of viruses

named for the crown-like spikes that cover them.

Theyre common in human and animal populations,

and many cause mild infections.

Some strains cause the common cold, for example.

But, the group also includes potentially serious stuff

like SARS and MERS

respiratory infections that cropped up in Asia and the Middle Eas

t in 2002 and 2012, respectively.

We know this new virus is not the same as either of those

because its entire genomewas quickly published

in a global epidemiological database.

But it can cause similar symptoms

, like fever and cough.

And like those two diseases,

infectious disease experts think it jumped into humans from animals,

making it a zoonosis or zoonotic disease.

Viruses are usually somewhat finicky about their hosts

because they have to get inside cells

and that means matching up to cellular parts,

sort of like having the right key for a really complex lock.

But, on really rare occasions,

a virus can just get lucky when it finds itself inside a new species.

Then, it can mutate and make itself more at home.

SARS, MERS and the novel coronavirus all probably originated in bats,

though they all took different routes to reach humans.

SARS, for example,

seems to have been transmitted to humans by civet cats,

while MERS was first transmitted through dromedary camels.

The viruses likely made their way

into people who came in close contact with those animals,

either because they cared for them or consumed them or their products.

Now, despite what you might have seen,

we dont yet know what species passed 2019-nCoV onto us.

The genetic data for the virus was released in mid-January,

so scientists are still looking for clues as to its animal host.

One paper that garnered a bit of media attention

suggested the virus jumped from a snake

an idea some people found believable since snakes

are often sold at the market where people first seemed to get sick.

But other experts are deeply skeptical.

Coronavirus infections have only been found in mammals and birds before.

So, a snake would be pretty unusual, and the studys evidence is pretty weak.

Plus, technically, we dont know for sure that the market was the source of the outbreak.

It seems likely

given the first four identified cases were people who worked there,

but researchers were able to identify older cases when they tested saved specimens.

In any event,

pinpointing the host it came from

is not really the top priority right now.

The main focus of researchers is how the virus is behaving in people.

Though the numbers change daily,

there have been over 4,500 confirmed cases of the virus,

almost all of which are within mainland China.

Small numbers of cases have also occurred in nearby Asian countries

and elsewhere in the world,

including Australia, France, the United States, and Canada.

Thats admittedly a lot of folks getting sick,

but its worth noting that its still really unclear

exactly how often it turns severe and how infectious this new virus really is.

While we know there is at least some human to human transmission,

we don't know how easy it is yet.

And just looking at one metric or another can be misleading.

For instance, a preliminary estimate

for the WHO put this virusbasic reproduction number,

sometimes called the R0, at around 1.4 to 2.5.

Its a measure of the transmissibility of an infection.

So, a value of 1.4 to 2.5 means each infected person

would be expected to infect two-ish other people,

once you average everything out.

That might seem bad

after all, as some have pointed out on the internets

, thats on par or higher than estimates for really bad epidemics,

like the 1918 flu and the 2014 Ebola outbreak.

And technically, thats true.

But its also not the whole story,

because you could just as easily say its about the same as the seasonal flu.

And an R0 by itself doesnt tell you how dangerous a disease is.

R0 is almost always based on mathematical models,

which can be unrepresentative of the real world at times.

Also, it assumes a completely susceptible population, and it can be influenced

and changedby human behavior.

For example the R0 value of ebola in west africa

is very different from the R0 value of ebola in America,

this isnt some intrinsic quality of the disease

But more to the point,

it tells you nothing about how sick people get when they are infected.

Its a measure of contagiousness, not virulence

the term epidemiologists use to refer to a diseases severity.

There are infections with much higher R0 values

which we dont freak out about because their fatality rates are very, very low.

Like, you probably didn't hear about the outbreak of really bad pink eye in Mexico in 2003,

even though it had an R0 of four! Because, well, no one dies from pink eye.

Epidemiologists worry about high R0s

because they indicate a fast-spreading pathogen,

and if a pathogen infects a lot of people,

then even a super low fatality rate can mean a lot of deaths.

And the fact is, we dont know what this new viruss fatality rate is yet.

SARS and especially MERS had high fatality rates,

but other coronaviruses dont.

To date, experts have estimated the new viruss fatality rate

to be about three percent, but even thats not likely to be accurate.

Its of a back-of-the-envelope calculation based on reported cases and deaths,

but the true number of infections is likely much higher,

as not everyone who gets infected becomes sick enough to see a doctor and have it confirmed

So the actual fatality rate is expected to be quite a bit lower

and already, its small compared to SARS or MERS.

Still, its high enough to be concerning

if the virus is allowed to transverse the globe unchecked.

Luckily, it appears that countries learned from both SARS and MERS,

and are working together to quickly respond to this disease.

China has implemented a variety of measures to minimize the spread of the virus,

including canceling Lunar New Year celebrations in Beijing.

And confirmed cases in other countries are being isolated to prevent the spread.

The rapid release of viral genome sequences in particular has also been praised by researchers,

as its let scientists around the world investigate the virus

and develop precise tests to detect it.

And vaccines are already being planned for development and testing.

So while this new virus isnt something to ignore,

all-out panic isnt warranted, either.

For now, the main concern is for people in China

and for those who have recently been to Wuhan

or nearby areas and their close contacts.

You can still take steps to protect yourself,

because that will help protect you from all sorts of other diseases.

If its anything like SARS and MERS,

the virus is probably spreading via the respiratory droplets

produced during coughing and sneezing.

Thats the same M.O. as influenza viruses,

so the usual measures you should take during flu season apply:

Wash your hands a lot

and stay home if you feel sick.

Andbonus!—

youll help protect yourself from the flu! Which,

just FYI, is a much bigger deal in the U.S. right now.

Were on track for an especially bad season,

with over 15 million infections so far, more than 140,000 hospitalizations. and over 8,000

deaths.

So if you havent already, get your flu shot! And dont panic about the coronavirus.

While the emergence of a new virus can be a really intense time,

infectious disease researchers around the world are on it.

Thanks for watching this episode of SciShow News!

Weve included some links in the description that have more up to date information on the

coronavirus,

so you can check those out if you want to learn more.

Also we have a quick announcement!

The team here at SciShow has got some really special episodes in the works,

so were actually going to be skipping our Saturday episodes in February.

Heres a hint: there were field trips involved!

So, well be six days a week instead of seven for a little bit.

We cant wait to show you what weve been working on!

[ outro ]

The Description of What We Know About the New Coronavirus