Two captions. issue #5

There are two options for captions of  the picture: the original and mine. Guess which is the former.
1. '"Quarantine means 40 days, not 90, go to work."
2. “You’re right. It is easier with the ball.”

Two captions. issue #4

There are two options for captions of  the picture: the original and mine.
1. “Who’s the clown in the suit?”
2. "Sir, are authorized to work under influence?"

Picky cusstomers vote with both hands FOR

buildup of herd immunity to covid-19.
On Sunday morning, I went to my hypermarket to buy some food. In the store, there are ads  everywhere, as if borrowed from the rules of the game of chess: "take-move " (touched-take). In the department of vegetables and fruits there are trays with beautiful strawberries. And for the second week I can see aesthetes who take one berry with their hands, examine it and put it back. I address  the management of large stores: "If you have published a rule, monitor its implementation." I guess, that a fine of $8 for one berry that was put back in the tray will solve all the problems of painful choice.  If the store managers have the task of building up a – herd immunity in the city, then such picky and indecisive customers are the ideal guides for this approach to fighting infection.
Now about the tests.

Chart1. Daily number of tests and cases of infection in Russia

The first  chart shows the number of tests and the percentage of infected people in Russia. The highs for the number of tests fall on Saturday and Sunday, and the lows -  on Tuesday and Wednesday. It is as if there is a background testing  with a low detection rate (2.5%) and there are people concerned about their health who come on weekends and raise the percentage of infected people up to 3.5 .

Chart 2. Weekly cycle of infection spikes in the US and Russia

The second chart shows the normalized distribution coefficients Rt n in the United States and in  Russia . In the US, the risk of catching the  infection is 35% higher on Saturday and Sunday than on Wednesday. It is possible that many Americans lead a more active social life over weekends, and, as a result, are more likely to become infected.

In Russia, the opposite picture is observed: The Rt n distribution coefficient is 13% higher on Tuesday-Wednesday than at the weekend. My version of the explanation is that in Russia people spend weekends at their dachas and, consequently, have fewer contacts than on weekdays.

Pro tests. continuation

Epigraph.

And then in normal light it appeared in black

What we value and love, what the team is proud of.

А потом в нормальном свете представало в черном цвете
То, что ценим мы и любим, чем гордится коллектив.
В.Высоцкий

It seems that even the virus realized that it could not frighten the people who overcame the Polovtsians with the Pechenegs. Since June 11, the Rt reproduction coefficient does not exceed 1.01 and is equal to 0.916 on June 19. Unfortunately, this coefficient can become a tool of manipulation in dishonest hands, since the number of detected cases is directly proportional to the number of tests. So that no one has any doubts about the reliability of the picture, we recalculated the Rt coefficient taking into account the number of tests conducted in Russia and the United States. The results are shown in figure 1.

Figure1. Rt and Rt n in Russia and USA

In the US, the normalized Rt n coefficient has become slightly more volatile compared to the classic one, and that's all. The situation in Russia is much more interesting. First, the weekly cycles became much clearer and the chart began to resemble the American one more and more. But most importantly, the picture of a decline of  infection, which is drawn by the usual Rt, has been replaced by cyclical fluctuations in the range of 0.84 -1.1, where there is no decline. On June 19, Rt n is equal to 1.094.

Two captions. issue #3

There are two options for captions of  the picture: the original and mine.

1. "One last thing ..."

2. "Finally, we have reached consensus that the main danger is global warming."

How to calculate the Rt reproduction number in your state, and why I don't expect peak in Russia before June 18

   During the first 3-4 weeks, the infection develops according to the classic scenario when the number of infected is easily calculated using the geometric progression formula. For Chinese flu, R0 (basic reproduction number) is 2...3, and the serial interval (the time between infections) is 5 days. Then the quarantine comes into effect, the number of patients who have been ill increases, and  Rt statistical number is used to assess the epidemy.
According to the Rospotrebnadzor (Russian Federal Service for Surveillance on Consumer Rights Protection) methodology, the Rt infection rate is an indicator that determines the average number of people infected by one patient before isolation. The Agency focuses on the regions on the transition to the I phase of the lifting of restrictions at a rate of less than 1.0; II phase - if Rt  is below 0.8.
   Is it possible to calculate this mysterious reproduction number in your state? Last Sunday I finally got to the Rospotrebnadzor manual and now I am happy to share its secret formula with the audience of my blog.

 

X1 ...X8  number of new cases a day. Rt =(X5+X6+X7+X8)/(X1+X2+X3+X4)

Now let's look at the dynamics of Rt in the US and in Russia. Day zero was taken when the number of cases exceeded 50. The comparison is particularly useful because the development of infection in America is 17 days ahead of Russian history. And if the Russian statistics is not very false, then we can predict what will happen in the next 2-3 weeks.

Rt in Russia and the US . X  axis -  days since the beginning of epidemic in the country.

The 7-day cycle of the Rt  in the US and its absence in Russia is immediately noticeable, but otherwise the indicators of development of infection  behave like twins. So, we can project that Russia is unlikely to reach the peak of epidemy before June 18.