CV19 infection rates are increasing, but death rates are decreasing?

  • Thread starter ElliotSmith
  • Start date
  • #1
136
59

Summary:

CV19 numbers are increasing, but deaths are decreasing, why?

Main Question or Discussion Point

CV19 infection numbers are increasing substantially throughout the world, but deaths from the virus are steadily decreasing, why is this?

Does this mean that the virus is becoming less virulent?
 

Answers and Replies

  • #2
Drakkith
Staff Emeritus
Science Advisor
20,853
4,599
Not necessarily. The US has experienced a resurgence in the number of cases here in the last week or so, but since the virus can take upwards of two weeks to manifest symptoms the death rate may lag behind the infection rate somewhat.

Also, and I say this with utterly no knowledge of if it's true or not, governments and healthcare workers may be getting better at dealing with cases as time passes and they gain experience, equipment, etc.

but deaths from the virus are steadily decreasing
Hmm. I just looked at the WHO website after typing the first part of the post and doesn't appear that deaths are decreasing. At best they appear to be relatively steady.
 
  • #3
PeroK
Science Advisor
Homework Helper
Insights Author
Gold Member
13,356
5,906
Hmm. I just looked at the WHO website after typing the first part of the post and doesn't appear that deaths are decreasing. At best they appear to be relatively steady.
Back in April/May the case rates were running at about 80,000 - 90,000 per day, and the death rate at 7,000 - 8,000 per day. In June the global case rate has increased to 125,000 - 190,000 per day, but the death rate is about 3,000 - 5,000 per day.

There is a large disparity between the first wave (which was predominantly Western Europe and North America) and the current wave (which is more generally everywhere except Western Europe).

In any case, there is also a huge disparity in the death rate geographically. See, for example:

https://www.physicsforums.com/threa...tainment-efforts.983707/page-141#post-6360819
 
  • #4
Drakkith
Staff Emeritus
Science Advisor
20,853
4,599
@PeroK My apologies, I was only looking at roughly the last month or so, as the OP seemed to me to be referring to the very recent past. I should have stated that in my post.
 
  • Like
Likes russ_watters
  • #5
atyy
Science Advisor
13,839
2,118
The number of confirmed cases may be fewer than the true number of cases, depending on how many people are tested and who is tested. So one must distinguish between the confirmed case fatality rate (CFR) and the infection fatality rate (IFR). The latter is the "true" death rate, whose estimate has not changed much. Early reports placed it between 0.3% to 1%, where it currently still is.
https://www.who.int/docs/default-so...0219-sitrep-30-covid-19.pdf?sfvrsn=3346b04f_2
https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30243-7/fulltext
https://www.nature.com/articles/d41586-020-01738-2

I have put "true" in quotes, as even if we detect all cases, improved treatment might reduce the death rate over time. Some of these improvements might be having health care systems that are not overwhelmed due to safe distancing measures slowing the spread of the disease, earlier oxygen for potentially severe cases, use of dexamethasone etc.
 
  • Like
Likes Ygggdrasil and russ_watters
  • #6
1,615
967
I think it's mostly due the change in the age distribution of (new) cases.
As I recall among the new cases the average age is rather low.

It would be interesting to see if there is any change in 'mortality ratio by age groups' type statistics over time. That could confirm whether there is anything else in this or not.
 
  • Like
Likes russ_watters, BillTre and PeroK
  • #7
jim mcnamara
Mentor
3,905
2,292
There has been a 10-14 day lag for mortalities to show a concomitant increase, as well. Mortalities for the same patient cohort are also down because the ICU physicians (in the US) have made advances in treatment as well as understanding the biochemistry and required pharmacology to cope with oxidative stress and subsequent inflammation (cytokine storm) - i.e, dexamethasone.

There is a lot more to this.

Consider viewing the Medcram Covid-19 ongoing series on youtube. Most are less then 15 minutes. Virtually every question that has been asked on PF has been given thorough and complete - as far as is known - answers that anyone with secondary school biology and freshman math/chemistry can immediately grasp.

Here is a list of all sessions - as of 18:43 6/30/2020

My current favorite session is the use of the DISCERN tool to weed out garbage or pointless covid-19 "information" content on the internet.
 
  • Informative
Likes Rive and Tom.G
  • #8
1,615
967
Mortalities for the same patient cohort are also down because the ICU physicians (in the US) have made advances in treatment as well as understanding the biochemistry and required pharmacology to cope with oxidative stress and subsequent inflammation (cytokine storm) - i.e, dexamethasone.
Could you please recommend a site with actual/up to date statistics of this kind?

Is there any change in hospitalization rate too?
 
  • Like
Likes Ygggdrasil
  • #9
jim mcnamara
Mentor
3,905
2,292
There is one RCT on dexamethasone which shows improved patient survival - the RECOVERY study was terminated early, data has been published. The trial was terminated early for ethical reasons: Patient improvement - start here
https://www.recoverytrial.net/

Dexamethasone is now in use, usually on a hospital by hispital basis which results in a crazy crazy quilt.
The CDC will have to suggest it officially before some entities will consider its use.

There are other ongoing RCT's so you can see what is being studied:
https://clinicaltrials.gov/ct2/search

Because of the unreliable nature of internet sources other than google scholar, use that search engine and you can search for clinical studies (largely observational, not RCT).

Example try 'covid-19 proning', 'covid-19 age class mortality'

There is no completely reliable mortality data US wide because of local regulations which result in some hard to understand results. In other words confounding (or confusing) reporting practices. The JHU site displays what is officially published by local entities. An example of 'hard to understand' is Texas. They do not report hospitalization rates and some other data, plus the number of deaths seems relatively low, IMO.

The dashboard boxes have switch bars so the main display will show various data as different colored round blobs - you can pick the level of administrative granularity - Admin0, Admin1, Admin2. This shows current death rates.

https://coronavirus.jhu.edu/ go into the dashboard
Use the analytics section and you can see relative death rate reductions in states over time. Or some increases, too. Decreasing mortality rates may also continue as the fraction of younger people under hospital care increases in in-patient populations.

Dexmethasone is a win, however.
 
  • Informative
Likes berkeman

Related Threads on CV19 infection rates are increasing, but death rates are decreasing?

  • Last Post
Replies
6
Views
26K
Replies
7
Views
424
Replies
2
Views
2K
Replies
6
Views
23K
Replies
52
Views
10K
Top