## Friday, April 02, 2021

### Impact of Covid within the Czech age-sex pyramid

According to the standard global Covid data, my Czech homeland is the world's #1 country above 1 million according to the "cases per capita" as well as "deaths per capita".

Note that this 2017 pyramid shows the local minimum of the width in the age of 15-19 which means that the "decline of the population" looked worst around 2000 and the natality started to grow again.

If we switch to our official national tables, the country of 10.7M (M is mega, a million) has detected 1.546M people as positively tested (14.4% of population) and 26,765 people have died with Covid so far (0.25% of population). It is generally agreed by the epidemiologists that the actual percentage of the population that has acquired Covid antibodies is at least around 50% and probably between 50% and 100% – and many of us think it is much closer to 100% than 50%.

Unlike the Swedes where the number of deaths is just 1/2 of our figure, the Czechs have "enjoyed" a lockdown for half a year now. At the individual level, however, I believe that Czechs have behaved much more freely than the Swedes or any other nation in the world and that's the main reason why we have maximized the per-capita numbers – and why we are seeing a truly natural, herd-immunity-dominated drop right now.

We can finally take the age-sex pyramid from the Czech Statistical Office and compare the number of people in various cohort-sex combinations with the numbers of cases and deaths according to the regional public health stations (KHS). The population will be divided to 9 age groups, with boundaries at 15,25, ... ,85.

0-14

Total population in the cohort (as of end of 2019): 1.71M
49.1% are female (the percentage is close to 50% up to age 55 or so)
78k+82k women+men positively tested (9%,9%)
1+1 dead (both 0.0001% of population, a bit over 0.001% of positively tested)

15-24

Total population in the cohort: 0.96M
48.6% are female
73k+72k women+men positively tested (15%,15%)
1+3 dead (0.0002%/0.0006% of population, 0.0014%/0.004% of positively tested)

25-34

Total population in the cohort: 1.37M
48.5% are female
104k+109k women+men positively tested (15%,16%)
16+33 dead (0.0025%/0.005% of population, 0.015%/0.03% of positively tested)

35-44

Total population in the cohort: 1.69M
48.4% are female
138k+130k women+men positively tested (17%,15%)
57+96 dead (0.007%/0.011% of population, 0.04%/0.07% of positively tested)

45-54

Total population in the cohort: 1.53M
48.8% are female
153k+137k women+men positively tested (20.5%,17.5%)
184+334 dead (both 0.024%/0.045% of population, 0.12%/0.24% of positively tested)

55-64

Total population in the cohort: 1.31M
50.6% are female (the youngest cohort where women lead)
104k+102k women+men positively tested (16%,16%)
542+1231 dead (0.08%/0.19% of population, 0.5%/1.2% of positively tested)

65-74

Total population in the cohort: 1.28M
54.7% are female (the youngest cohort where women lead clearly)
69k+66k women+men positively tested (10%,11.5%)
2172+4384 dead (0.3%/0.75% of population, 3%/6.5% of positively tested)

75-84

Total population in the cohort: 0.64M
60.5% are female (the ratio of women-to-men is some 3-to-2 here)
44k+32k women+men positively tested (11.5%,12.5%)
4113+5805 dead (1.1%/1.3% of population, 9.5%/18% of positively tested)

85+

Total population in the cohort: 0.21M
69.6% are female (the women-to-men ratio exceeds 2-to-1)
23k+10k women+men positively tested (15.5%,15.5%)
4046+3155 dead (2.8%/5% of population, 17.5%/31% of positively tested)

Verbal commentary

You can see that the very old people were not protected in any visible way whatsoever. 15% of Czechs have been PCR positively tested and the percentage is the same in the 85+ cohort. (But maybe it's because the very old ones were much more intensely tested to they have a much higher number of negative tests. Note that kids were largely shielded from testing.)

The cohort 65-84 got a bit closer to 12% so it was reduced there while the percentage is 17-20% in the "productive" 35-54 bracket. In the real world, the protection of the vulnerable was pretty much another fairy-tale. However, there are signs that vaccination did reduce the mortality and because the vaccination focused on the elderly (plus ill, plus teachers and doctors), the vaccination is the main reason why the average Covid death in 2021 is some 2 years lower than in 2020, I believe, although the attribution is never quite certain.

Concerning the dead, the percentage of men who died is higher than for women, some 3-to-2, in all age groups except for 0-14 (where we have 1 fatality in each sex). Among the kids, 0.0001% of the cohort has died from Covid; it is still around 0.001% of the demonstrably PCR positively tested ones. Up to the age of 54, we are still at 0.02% of all the people in the cohort who died from Covid; and some 0.1%-0.2% of the positively tested ones. It's very possible that up to the age of 54, flu is more dangerous once you get both.

All these percentages increase by a factor of 3-4 for each extra decade of age.

In the age of 85 years and older, 3% of women and 5% of men from the whole nation's cohort have died with Covid. The percentage becomes more brutal if the denominator involves just the people who were positively PCR-tested. Then it is 17.5% for women and 31% for men. Even as a man in the oldest cohort who is positively tested, you are still "more likely than not" to survive but 31% is a huge risk, indeed. (But even among 85+ years old men, the 5% death rate that is calculated from the whole nation could be closer to the real CFR than the 31% case fatality rate computed from the positively tested ones because even in this group, a majority of the positive men has avoided getting a positive PCR test, I believe.) You don't want to be a positively tested super old man. Also, you don't want to go to the Covid ICU because some have claimed that 7/8 of those who visit a Covid ICU die. This number makes the ICU look not like "a tool to cure the people from Covid" but as a buffer before the crematorium.

Note that the percentage of seniors – people who are getting a pension – who have died with Covid is still comparable to 1% of the nation so the pension savings, 1%, are negligible relatively to the typical annual increases of the pension money. Some of the long-term patients who may have been costly for the healthcare system also died with Covid but this is probably going to be at most a few percent of the hospitals' expenses, too. Some people have naive opinions that some huge money may have been saved for the pensions or healthcare expenses because the people have died but even these numbers are absolutely negligible relatively to the losses caused by the nationwide lockdowns.