Thread by @ashishkjha

With US averaging 1200 COVID deaths daily

Things look bad

But there is some good news. May be

Case Fatality Rate is dropping

In fact, CFR down 50% over past 6 weeks

That's good. Mostly

Because its driven largely by who is increasingly getting infected

Kids

Thread

Background

One strange feature of our Delta surge is that our CFR has been VERY high

Other countries like UK have had much lower CFR

They've seen a disconnect between infections & deaths

Largely because they did a fabulous job vaccinating the elderly

The US? not as much

2/6

In UK about 95% of elderly fully vaccinated

In US? About 80%

Impact is clear in our high death rates

But first, lets talk CFR

CFR is cases leading to deaths -- with a lag

How much lag? Many of us use 22 days

So a death on July 23 is from a case on July 1

On average

3/6

On July 1, there were about 13,500 cases

On July 23, about 325 deaths

So CFR from 7/1 cases about 2.4%

BTW, UK CFRs are closer to 0.2% to 0.4%

July 15: US had 26K cases

22 days later, 500 deaths

CFR from 7/15 about 2%

CFR from 8/1 about 1.5%

CFR from 8/7 about 1.2%

Deaths today are cases from about Aug 8

And CFR today (1.2%) half of CFR from July 1 cases (2.4%)

So what's happening?

Three possibilities

1. We are testing more, finding more cases

2. We're getting better at treating COVID

3. Different folks getting infected

5/7

Are we testing more, finding more cases?

No

Test positivity is up

Testing is NOT keeping up with cases

So that's not it

2. Are we getting better at treating COVID?

Over course of pandemic? Sure

Over past 6 weeks? No

In fact, as hospitals fill, we're likely getting worse

So are different folks are getting infected?

Yes

On July 1, rate of infections among 5-11 year-olds was about the same as that of 65-74 year-olds

By mid-August

5-11 year-olds had seen a 900% increase in cases from July 1

65-74 year-olds had seen 500% increase

7/9

So infection demographics are turning decidedly younger

And rate of increase in 5-11 year-olds is outpacing pretty much everyone else

This group, of course is unvaccinated

While >65 unvaccinated pool is smaller and luckily shrinking

That's good -- leads to fewer deaths

8/9

What does this all mean?

I'm hoping that as infections continue to rise

We will see flattening of deaths

Deaths will rise from where we are today

Just at a slower pace

But there is a problem

Kids are getting infected at much higher rates

Especially 5-11 year-olds

Raises urgency of vaccinating this population

I know FDA being VERY careful about making sure vaccines are safe in kids 5-11

Good

But there is a cost to waiting until every box is checked

Young kids getting infected at very high rates

And need the protection of vaccines

End