Name: Why coronavirus death rates are so different
Uploaded: 2021-01-04T07:49:31.000Z
Duration: 4 min 41 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Your boss, the head of the WHO, put out a mortality rate number yesterday

Adverbs of manner

Unlike Italy where the mortality rate is around 10%, the rate in the US

So why are Covid-19 fatality rates so varied?

Well, firstly, there's not just one rate.

There's one that helps you understand an outbreak.

And then there's two more, which will tell you the risk of dying.

During the outbreak of a new disease, you likely only know that some people have

been infected and some of those people have sadly died.

If 10 people have been infected and one infection has ended in fatality,

is tempting to conclude that this illness has a fatality rate of 1 in 10 or 10%.

The problem is that there's a time lag between when someone gets infected and

when they either recover or succumb to the illness.

To get a more accurate number, you should only count those cases

In this example, five infections have resolved so by excluding unresolved cases,

as we should, our fatality rate has risen to 20%.

It's the number that you've probably been hearing the most.

We can separate big populations into smaller groups

And we can also see how effective different treatments are.

Remember, there are two other fatality rates for that,

Well especially early on in an outbreak we're still missing lots of information.

We definitely haven't counted all infected people.

We're missing those that have not been tested.

We're missing those that didn't seek medical attention

If we found lots of these cases, it would bring our fatality rate down.

But early on, we just can't be sure about how big these groups are.

If a person with another serious condition gets infected and then dies,

is that a fatality from the infection or from the condition?

In some places, Covid-19 fatality counts have initially only included those

with delays in counting fatalities in people's homes and care homes.

So when the count  eventually catches up the fatality rate will rise.

So over time, as we fill in the gaps in our knowledge,

our case fatality rate will get closer to the number we probably want to know:

but our case fatality rate will never get us completely there.

Because by definition we're only counting known cases.

We could be missing loads of hidden infections.

To try to fill in these gaps and tell us our risk of dying we can turn to our last two rates.

It tells us the risk of dying if you get infected.

This is achieved by randomly testing a group of people.

giving us a truer representation of the number of infections.

And subsequently, what share ended with a fatality.

That tells us the risk of dying relative to the whole population.

Or put another way, what portion of the population has died from this disease.

But because we don't know how many people will end up being infected.

We won't know this figure until the disease has run its course.

So, we have three types of fatality rate:

two that give us a risk of dying for those infected and whole populations.

And a third that, though dealing with partial information, is incredibly useful

for understanding of disease and understanding which treatments are most effective.

Knowing what these numbers are for and what information they're based on

means that we can use them more effectively.

Subtitles ListPlay Video

Why coronavirus death rates are so different

vulnerable

eventually

incredibly

figure