The official Czech government's sampling measurement of the herd immunity (something I was recommending already three months ago) concluded that only 0.4% (out of the 25k sample) of Czechs had antibodies against Covid-19. Well, that's rather implausible although I can't "rigorously" show that this figure is impossibly low. That number of "cases" (40,000) would surpass the officially "confirmed cases" only by a factor of 5 or so.
The Strakonice Castle. Strakonice is also famous for the legend (and a theater play) about Švanda the Titman. He wanted to marry a babe but her family thought he was poor. So he decided to earn the millions by playing the bagpipes. Fortunately, his mother was a fairy who turned the bagpipes to magic ones. He could enchant even princesses... however, an aide wanted to rob him etc.
But antibody tests are subtle and diverse and the details matter.
A new test in South Bohemia led by Martin Kuba (ODS) has ended up with a very different result. 5% of the Czechs have already developed Covid-19 IgA antibodies (early antibodies to fight against the infection). Note that due to this "IgA", this South Bohemian test looks a notch more transparent and well-defined than the nationwide one. We weren't really told at all "what kind of a test" the damn government experiment was using.
(Other types of relevant antibodies are IgG, IgM, and neutralization antibodies. You're invited to study this topic more deeply. Update: The government has used the rapid test WANTAI which should be able to measure IgG and IgM antibodies.)
If 5% of Czechs have been exposed to the disease, it's some 500,000 people. Out of them, 300 or so have died, so the percentage of those exposed who die is some 0.06%, below that of flu.
In fact, it seems plausible that the right number is much lower than that because the figure 5% seems to be one for the Písek and Strakonice district which, according to our district map of Covid, have 12 and 52 "confirmed cases" of Covid per 100,000 people.
Písek boasts the oldest bridge in Czechia
Czechia has some 8400 confirmed cases, about 80 per 100,000 people, which is about 2-3 times the average of the Písek and Strakonice districts. With this doubling or tripling, it could be that 10% or 15% of people in Czechia have been exposed to the virus sufficiently to have the IgA antibodies.
For the three numbers of "exposed Czechs with antibodies", 500,000 and 1,000,000 and 1,500,000, you get the case fatality rates of 0.06% and 0.03% and 0.02%, respectively, well below that of flu (especially the last two). And because Covid is even more innocent for the younger cohorts, you could be even more certain about the fact that Covid is less dangerous than flu among these cohorts. It's probably reversed for the oldest (and obese, sick...) people.
I am still shocked by the meltdown that most of nations has undergone because of this little cough. In recent days, we saw the GDP data for Q1 of 2020. Only two weeks were affected by a real lockdown in Q1 in the "fast moving countries" like Czechia. Nevertheless, the EU, the Eurozone, as well as Czechia have seen some 3.5% quarter-on-quarter decrease of the GDP. It was 2.2% in Germany but over 5% in Slovakia!
And what about Sweden which avoided the lockdown dictate? Its GDP also shrank on the q-o-q basis but only by 0.3%. That's pretty incredible. I am so jealous.
In the second quarter, Q2 of 2020, we have had 8 similar lockdown weeks instead of 2. So the q-o-q increase of such weeks is 8-2=6, a tripled increment relatively to the Q1 one (two weeks), so the q-o-q decrease of the GDP may be predicted to be thrice the Q1 figure. So I expect the EU, the Eurozone, and Czechia to drop by 10% in Q2 in the q-o-q sense. The prediction for Sweden could be just a 1% drop. Well, I am pretty sure that it will be deeper e.g. because Volvo has also suspended the production. But the absolute difference between the Swedish drop and the European drop may be even more striking in Q2 than it was in Q1.
What have the nations achieved by this insane lockdown? Almost all countries obsessed with this virus were (and perhaps are) dreaming about having the same results as Czechia. We have peaked at some 380 new cases a day, 18 deaths a day, and 450 hospitalized people. Now we're getting roughly 50 new infections per day, 3 deaths per day (that's delayed, from the buffer), below 200 are hospitalized, and below 40 are active serious (defined as either ventilators or extra-body blood circulation, or a more severe patient who would get one of these things if he or she would be deemed "ready to withstand this treatment"). Clearly, we could send the disease in the direction of disappearance (\(R_0=0.7\lt 1\)) and the total number of cases and fatalities has been getting convergent while much lower than in any Western European country (per 10 million people).
However, rationally speaking, we're in a very similar situation as in the mid March or so. The number of new cases per day isn't too different, the number of daily fatalities isn't too different. We have just bought a delay of 2 months for a trillion crowns. We are heroically reopening and it's being justified by the good dynamics of the disease. But the daily increments are pretty much exactly the same as the daily increments in those March days when we equally enthusiastically started this lockdown! ;-)
Can't you see how insane it is? In mid March, we had the same "rate of growth" of the disease as we have now – so with a coherent logic, we could have done the reopening in mid March, too.
OK, if 5% or 15% of the people have IgA antibodies (which they didn't have before, but it's hard to be certain about this claim), then it's clear that the disease will be propagating less quickly than it would propagate without any restrictions back in March. But the difference is arguably not game-changing. Whatever we will see now could have been obtained in mid March without the lockdown, too.
So the real reason why countries like mine are reopening isn't any characteristic of the recent dynamics of the virus itself. Instead, the true reason behind the reopening is the evaporation of the totally irrational hysteria about this stupid, insanely overrated, little cough; plus the people's realization that one really can't do such things for many months let alone a year. We're reopening because millions of people have regained their composure and abandoned this insane hysteria about that medical little event which is not far from a non-event.
Too bad, most of them won't even admit they were shockingly irrational and stupid and they have failed a test of their lifetime – and contributed to the liquidation of 10+ percent of the GDP, much of which will be absent in the medium term, not just short term.