(pleasant orchestral music)
- [Narrator] This line tells a story.
The story changes depending
on whether the line climbs up,
plateaus, or the line goes down.
What do the lines created
by COVID-19 data tell us?
- The best thing to do
is look at the local data
because things are varying quite a bit,
not only country to
country, but state to state
and even within different counties
there is rapidly different spread
depending on what's going
on in your community,
so it's helpful to look at
different things together,
including cases,
hospitalizations, and deaths.
A lot of these metrics vary
based on who's reporting it
and they're reporting them
in slightly different ways.
The number of confirmed
cases is likely lower
than the number of actual cases
because not everyone has been tested
and a lot of the milder
or asymptomatic cases
were likely missed, especially
earlier on in the pandemic.
- [Narrator] States have
different ways of keeping track
of how many people are in the hospital
being treated for COVID-19.
Some states don't report this
and the Centers for Disease
Control and Prevention
doesn't require it.
(monitor beeping)
- [Brianna] You'll have people reporting
the number of people currently
hospitalized for COVID,
the total number over time,
who's in the intensive care unit,
and then some states also give you age
and underlying health condition data
and other demographics,
such as race and ethnicity,
though that's not uniform
across everywhere.
So the hospitalization
data that you're gonna find
depends a lot on where you are.
States and counties also have
slightly different methods
for counting deaths,
but it's one of the more solid data points
that we have to actually figure out
how far and how severely
the disease has spread,
but like the number of confirmed cases,
the number of COVID deaths
is also likely higher,
especially since we didn't
test a lot of people
sort of in the beginning of the pandemic.
- [Narrator] Some states are going back
and counting deaths presumed
to be from COVID-19.
That may skew the trend.
- Sometimes what you'll see
is a spike in deaths in some states.
That recently happened in New Jersey
when there was a spike, but actually,
they just went back and added
a lot of their presumed deaths
to their total death count.
- [Narrator] There is a metric
lag between the data points,
confirmed cases,
hospitalizations, and deaths.
- [Brianna] First, as people
start to show symptoms
and get tested, you'll likely see cases
followed a week or so by hospitalizations,
and then deaths usually lag behind those
because usually with this disease,
people are sick for a few
weeks before they die.
- [Narrator] Public health
authorities also track
the positivity rate
that compares the number of
tests that come back positive
with the total number of COVID-19 tests.
- So if the positivity rate is high,
that likely means that all
of the cases in the area
aren't necessarily being caught,
but if the positivity rate is low,
most of the cases are
likely being captured
and you're probably doing enough testing
to capture all of the cases,
but keeping track of how the
positivity rate is changing
now that there is wider
spread testing is important
because if the positivity
rate is going up over time
in a specific area, that likely means
that there are more cases being found
and the disease is spreading.
Sometimes there are spikes or
ebbs or different patterns.
Like, for instance,
case and death reporting
usually slows down on the weekends,
and so it's important to look at averages,
whether or not it's over
five days or seven days,
to sort of smooth out all of those lags
and look at the trends over time,
because looking at just one day
or just the last couple of days
likely isn't going to
give you a clear picture.
(serene orchestral music)
