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Chemistry COVID pandemic Science vaccines

Studies on COVID-19 Lethality

Reposted from Swiss Policy Research

Updated: July 2021
Published: May 2020
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[Editor: the following is a bit sciency but is well worth the study.]

Overview

1) Antibody studies  2) Immunology  3) Median age of death  4) Hospitalizations  5) Nursing homes  6) Overall mortality  7) Influenza comparison  8) Seroprevalence per country 

1) Antibody studies

The covid infection fatality rate (IFR) depends on demographics (age and risk structure), public policies (e.g. protection of care homes), and medical treatment quality. In most Western countries, the median age of covid deaths is 80+ years and about 50% of deaths occurred in care homes (s.b.)

For comparison, the IFR of seasonal influenza, against which prior immunity and vaccines exist, is about 0.05% to 0.1%; the IFR of epidemic and medium pandemic influenza, such as in 1936, 1951, 1957 and 1968, is about 0.3%; the IFR of the 1918 pandemic influenza was about 2%. (Source)

In terms of covid-19 IFRs, an important difference exists between places with and without a partial or total collapse of local health and elderly care, and between the early and late pandemic phase. In the following table, NNH refers to the non-nursing home population (see section 5).

CountryPublishedPopulationIFR (%)Source
Global
Low estimateOct. 202051 locations
Below 70 years
0.20¹
0.04¹
Ioannidis
High estimateSept. 202024 locations0.68GMK
Africa
KenyaJuly 2020National<0.1Uyoga
MalawiAug. 2020National<0.1Grace
Asia
IndiaJuly 2020Delhi
Mumbai
0.14
0.23
India
IndonesiaJan. 2021National0.10UOI
IranMay 2020Guilan province0.12Shakiba
Europe
AustriaJune 2020Ischgl (NNH)0.26von Laer
BelgiumDec. 2020General population
Incl. care homes
40 to 49 years
0.58
1.47
0.05
Hens
DenmarkApril 2020Blood donors (<70y)0.08Erikstrup
EnglandAug. 2020
(low est.)
General (MCT)
General (ONS)
0.30
0.49
CEBM
Aug. 2020
(high est.)
General population
Incl. care homes
45 to 64 years
Below 44 years
0.90
1.43
0.50
0.03
Ward
GermanyMay 2020
Nov. 2020
Heinsberg (NNH)
Munich (NNH)
0.36
0.48²
Streeck
LMU
IcelandSept. 2020General population
Below 70 years
0.30
0.10
NEJM
Italy
(Lombardy)
Aug. 2020Below 70 years
Below 50 years
80+, first phase
80+, second ph.
0.43
<0.01
30.40
8.10
Poletti
Spain
(early phase)
Aug. 2020Confirmed covid
Excess deaths
Below 50 years
Below 40 years
0.82
1.07
<0.10
<0.03
Pollan
SwedenJune 2020Stockholm (NNH)
Stockholm <70y
0.35³
0.09
FOHM
SwitzerlandJuly 2020
Aug. 2020
Geneva (NNH)
Zurich (NNH)
0.324
0.304
Perez
Aguzzi
Latin America
BrazilSept. 2020
Sept. 2020
Maranhao
Manaus
0.17
0.28
da Silva
Buss
ColombiaJune 2021National0.27Guzman
United States
IndianaSept. 2020General population0.26AIM
Santa ClaraApril 2020General population0.175Bendavid
Miami-DadeApril 2020General population0.185Miami
Los AngelesApril 2020General population0.205Sood
New York City
(early phase)
June 2020Overall0.70Stadlbauer
June 2020Confirmed
Probable
25 to 44 y.
<25 years
1.10
1.45
0.12
0.01
Yang

1) Median values; 2) 0.76% including nursing homes (36% of deaths); 3) 0.58% including Stockholm nursing homes (about 40% of deaths, see page 23); 4) 0.64% and 0.60% including nursing homes;  5) These US studies may underestimate the true IFR, as they were done early during an accelerating pandemic.

Belgium: IFRs for entire population vs. non-nursing home population (Molenberghs)

The above chart shows the very significant difference between IFRs in the entire population (including nursing homes, left) and in the non-nursing home population (right) at the example of Belgium. The IFR in 85-year-old nursing home patients (about 20%) is almost 20 times higher than the IFR in people of the same age outside of nursing homes (about 1%).

2) Immunological aspects

Immunological research indicates that serological antibody studies, which measure antibodies in the blood (mostly IgG), may detect only about 50% to 80% of all coronavirus infections, depending on the sensitivity of the assay, the timing of the test, and the population tested.

This is because some people neutralize the coronavirus primarily with their mucosal (IgA) or cellular (T-cells) immune system and develop only mild symptoms or no symptoms. These people may develop no measurable IgG antibodies or may show them only for a certain time.

The following chart shows that six months after an infection, the sensitivity of antibody assays in non-hospitalized patients ranged from 98% (e.g. Roche) to just 30% (e.g. the widely used Abbott assay). Thus, some antibody studies may underestimate infections and overestimate IFRs.

Sensitivity of various coronavirus antibody assays (Peluso et al)

3) Median age of Covid-19 deaths per country

Half of all deaths were below, half were above the median age.

CountryMedian ageSource
Australia82 yearsDOH
Austria82 yearsEMS
Belgium86 yearsIBS
Brazil70 yearsMDX
Canada86 yearsHCSC
England82 yearsNHS
France84 yearsSPF
Germany83 yearsRKI
Italy82 yearsISS
South Africa62 yearsSAC
Spain82 yearsMDS
Sweden84 yearsFOHM
Switzerland86 yearsBAG
USA78 yearsCDC

The following chart shows the percentage of covid deaths per age group in various countries. While in many European countries, up to 90% of deaths affect people older than 70 years of age, in many Latin American countries, up to a third of deaths affect people younger than 60 years of age.

Percentage of covid deaths per age group, per country, by February 2021 (Sinichol)

4) Hospitalization rate

Initial estimates based on Chinese data assumed a very high 20% hospitalization rate, which led to the strategy of ‘flattening the curve’ to avoid overburdening hospitals. However, population-based antibody studies (see above) have since shown that actual hospitalization rates are closer to 2%, which is comparable to hospitalization rates for influenza (1 to 2%).

The US CDC found that Covid-19 hospitalization rates for people aged 65 and over are “within ranges of influenza hospitalization rates”, with rates somewhat higher for people aged 18 to 64, but “much lower” (compared to influenza) for people under 18.

In hotspots like New York City, the hospitalization rate based on antibody studies was about 2.5% (20% or 1.7 million people with antibodies and 43,000 hospitalizations by early May 2020). The lower-than-expected hospitalization rate may explain why many covid-19 ‘field hospitals’, e.g. in the US and the UK, remained largely unused.

5) Percentage of Covid-19 deaths in care homes

In most Western countries, deaths in care homes account for 30% to 60% of all covid deaths. In Canada and some US states, care homes account for up to 80% of all covid-related deaths. In Sweden, deaths in nursing homes and nursing apartments account for 70% of all deaths.

Percentage of covid deaths in care homes (Source: LTC Covid, February 2021)

6) Overall mortality

By the end of March 2021, there were close to 3 million covid deaths in close to 8 billion people. At a global infection attack rate of 10% to 30%, this results in an average global covid lethality (IFR) of 0.1% to 0.35% and a global covid mortality of about 0.035%. By comparison, the 1918 flu pandemic had a global mortality of about 2.3% (40 million deaths in 1.8 billion people).

See alsoCovid-19 Mortality: An Overview (March 2021)

Global covid deaths vs. all-cause deaths (S)
US: Yearly age-adjusted mortality (S)
UK: Mortality since 1842, age-adjusted (S)
Sweden: Mortality since 1851 (S)
German mortality since 1990 (S)
Switzerland: Mortality 1900-2020 (S)

A comparison between the number of coronavirus deaths predicted by the influential model of Imperial College London (no measures or moderate measures) and the actual number of deaths in Sweden indicates that the model significantly overestimated the impact of the epidemic:

Sweden: ICL model predictions versus actual Covid-19 deaths (HTY/FOHM)

7) Coronavirus vs. influenza pandemics

The following chart shows US mortality by age in previous pandemic years compared to 2020 US excess mortality, which consisted primarily (>75%) of confirmed and suspected covid-19 deaths, according to the CDC. To learn more about this comparison, please read this article.

Pneumonia and influenza mortality by age in previous pandemic years (Glezen, 1996) vs. 2020 excess mortality by age, primarily driven by covid-19, overall and excluding nursing homes (SPR based on CDC data)

8) Antibody seroprevalence per country

Percentage of people with measurable antibodies to the new coronavirus.

CountryDateRegionAntibodiesSource
Europe
BelgiumJune 2020National
Brussels
7%
12%
Herzog
DenmarkNov. 2020
Aug. 2020
National
Copenhagen
3.9%
3.2%
SSI
SSI
EnglandJuly 2020National
North West
London
6%
12%
17%
PHE
FranceMar. 2021National
Paris region
21%
37%
PFR
GermanyMar. 2021
Dec. 2020
June 2020
April 2020
National
National
National
Gangelt
15%
5%
<2%
15%
RKI
HungaryJune 2020National
Budapest
0.7%
0.8%
Merkely
IcelandJuly 2020National0.9%NEJM
IrelandAug. 2020National
Dublin
1.7%
3.1%
HSPC
ItalyJuly 2020National
Bergamo
Lombardy
Sicily
2.5%
38%
7.5%
0.3%
ISTAT
NetherlandsJuly 2020National
South
4%
16%
RIVM
PolandMay 2021Wrocław (IgG)
Wrocław (IgA)
35%
52%
Budziar
RussiaJune 2020National
Moscow
Petersburg
14%
20%
5.7%
TMT
TMT
EUSP
SpainDec. 2020
Dec. 2020
National
Madrid
10%
19%
Franco
SwedenMay 2020
Nov. 2020
National
Stockholm
5%
31%
FOHM
DNSE
SwitzerlandJan. 2021
Nov. 2020
Jan. 2021
June 2021
Zurich
Ticino
Geneva
Geneva
11%
16%
21%
33%
BAG


UGE
UkraineJan. 2021National43%LNMU
Americas
BrazilAug. 2020
Feb. 2021
Maranhao
Sao Paulo
40%
25%
Silva
SPS
CanadaJune 2020National
Quebec
Ottawa
Vancouver
0.7%
2.2%
1.3%
0.6%
BCA
USAMar. 2021
Mar. 2021

National
New York
Oregon
S. Dakota
35%
35%
11%
48%
CDC
C19P
Asia
ChinaApr. 2020


May 2020
Wuhan
Hubei
Rest
Wuhan
4.5%
0.5%
<0.1%
2.4%
Lancet


CMI
IndiaJuly 2021
June 2021
Jan. 2021
National
Delhi
National
68%
60%
22%
ICMR
Misra
NCDC
IndonesiaJan. 2021
Mar. 2021
National
National
15%
45%
Govt.
DKI
IranJuly 2020National
Qom
Rasht
17.1%
58.5%
72.6%
Lancet
JapanJuly 2020Tokyo1.2%Nawa
Saudi ArabiaAug. 2020
Nov. 2020
National
National
10%
20%
Alharbi
South KoreaOct. 2020National0.6%Lee
Africa
CongoJuly 2020Brazzaville20%IJID
KenyaJune 2020National
Nairobi
5.2%
8.3%
Uyoga
NigeriaOct. 2020Lagos23%NCDC
South AfricaJan. 2021National50%MDX
Estimated national immunity levels per country by December 2020 (Source: Bloomberg)

See also

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By John Gideon Hartnett

Dr John G. Hartnett is an Australian physicist and cosmologist, and a Christian with a biblical creationist worldview. He received a B.Sc. (Hons) and Ph.D. (with distinction) in Physics from The University of Western Australia, W.A., Australia. He was an Australian Research Council (ARC) Discovery Outstanding Researcher Award (DORA) fellow at the University of Adelaide, with rank of Associate Professor. Now he is retired. He has published more than 200 papers in scientific journals, book chapters and conference proceedings.

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