Plateau for start

Graph 1 Total number of cases, number of active cases, and rate of change in the United States, logarithmic scale.

   On May 30, there was maximum number of active cases (1 176 025),  on June 16, it was surpassed (1 186 227). The number of active cases on July 1, 2020 is 1 454 397.

Graph 2 Daily number of tests and percentage of detected cases in the United States

   On June 14 (111 day of the epidemic), the minimum percentage of detected cases (2.8%) was reached and the trend reversed.

Graph 3 Graph of the total number of infected  people and  number of active cases in Russia

   Although the infection in Russia started 19 days later than in the United States, the percentage of active  cases in Russia is significantly lower.

Graph 4 Daily number of tests and percentage of detected  cases in Russia

   "Saw" in number of tests characterizes the work of laboratories: war by war, and the lunch is by schedule. It is possible that many of them do not work on weekends. On June 30, the epidemic reached another minimum of 1.9 % on day 106 from the beginning of the epidemic.

Graph 5 Charts of normalized Rt reproduction number in the USA and Russia

   If Rt n is greater than 1, the infection widens, and if it less than 1, it fades. In the US, the plateau was not a maximum, but a respite before real growth. In this graph, the difference between the beginning of the epidemic in the United States and Russia is not 19 but 21 days, to  align weekly cycles. As you can see the risk to catch the desease in the US is, at least 30% higher on Saturdays, than on Tuesdays.
   Whether Russia will follow the well-trodden American path, or Russians mostly overcome the desease, will be revealed in a week.

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.

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.

"Sovereign" statistics as an alternative to the IgG test

On June 1, several of my friends who work at RSC Energia come out of quarantine. On may 5, their General Manager died from covid-19. On April 1, when the quarantine was introduced, 2,776 infected people were detected in the country, and on May 30  the number was  396,575. In other words, General Manager E. Mikrin was infected at a time when the probability of getting sick was 140 times lower than today. I do not think that in the case of complications, the chances of survival for ordinary employees are higher than for their General Manager, but the chances of getting sick have increased many times: in transport, in the factory canteen, and especially during a 9-hour stay in the office. President Trump demonstrates that he is with the people of America (every citizen received $1,200), he holds meetings, and almost every day communicates with journalists. Our situation is somewhat different with the President and with the help to Russian citizens. It is clear that the National Welfare Fund (169 $ billlion) is not to fight some Chinese flu, but to protect against a cheeky ("nahalny") threat.
But now it would be possible to help those who from June 1 will be packed into trains and buses, work in offices and enterprises so their taxes will go to the budget as a result. Before authorities  throw them into  the Red zone, they could ensure some safety by conducting free tests on antibodies (IgG class immunoglobulins), because today the cost of such a test in the Moscow region is $66 , and the result could be only in 7 days.
Now about the wonders of "sovereign" statistics. The first graph shows the number of cases and the number of people still ill in the United States. Their ratio is 65.2%. The time to double the number of infected people in the country is 53 days.

Pro tests

Our assumption that Italy and Spain passed the maximum number of active cases of infection in mid-April has confirmed. Today's table differs from the previous one by adding three columns: the Absolute number of tests, the Relative number of tests, and the Relative number of detected cases. Also, Peru was added instead of China due to the lack of Chinese statistics of tests.

Table 1 shows that in comparison with the Asian stage, a greater number of days is required to reach the maximum number of active cases: previously, 20-40 days, now - 80-90.

Tab.1

More than 5% of the population was tested in Spain, Belgium, Portugal and Israel, and less than 1% - in Iran, Brazil and India. (Hist.1)

Hist.1 Relative to the population number of tests (blue) and the relative number of infected (red)

In terms of the relative number of infected, the USA, Spain and Belgium are ahead (more than 0.4% of the population), tailing  Brazil, South Korea, India and Australia-less than 0.1%. (Chart 1)

Chart 1 Number of infected as a percentage of the population (blue) and number of deaths per 100,000 population (red)

More than 32 deaths per 100,000 population: in Belgium, Spain, Italy, Britain, France, Sweden and the Netherlands. Less than 9 – in India, Australia, South Korea, Russia, Israel, Turkey, Austria, Brazil, Peru and Iran.In Table 1, the 4th column from the end shows the countries that passed the first wave of the epidemic. In the third column from the end, the yellow cells indicate that the wave is close to its apogee and the brown ones indicate countries where the end is not yet visible – Peru, Brazil, Russia, Sweden and India.

The most backward medicine - in three neighboring countries, where the number of deaths relative to the number of cases is highest, %:·

3     Britain    14.4·

2     France   15.3·

1     Belgium  16.4.

And, the most intriguing, 4 countries with the most advanced medicine. In the 4-th column of  Tab.1 you can see number of deaths relative to detected cases, %. The leaders are:·

4       S.Korea     2.4·

3       Israel         1.6·

2       Australia    1.4

Based on official data, country that has the best equipped medicine in the world with the most professional doctors is drum roll :

1        Russia       0.9.

Forecast for April 13 (one month since the beginning of the epidemic in Russia)

On April 8, 2020, Prime Minister Mishustin proudly reported: "About 800 thousand studies (tests for COVID-19) have already been done." The cost of the test in impoverished Russia is $16. For friends, a good business with a turnover of $800  million (50 million tests) is being hatched. Will the aplomb of a fresh Prime Minister remain in May, when the country will receive 800,000 infected people for 800,000 tests, made  in April?  For comparison, in a prosperous Germany, 200 thousand tests  are conducted  for FREE every Day. The government is responsible for all expenses.  Since April 5, has been testing for antibodies to the coronavirus randomly selected 4,500 people in Munich, in order to understand what percentage of the city's residents are currently ill with COVID-19, and, also, what is the proportion of those who have already been ill, having developed antibodies to SARS-CoV-2. The experiment will last 4 weeks.

Dynamics for 3.5 weeks

In Russia, the epidemic has been slowing since the end of March. The period for doubling the number of cases increased from 2.7 days in mid-March to 4.6 days in early April. If we compare the doubling time with the United States, then on April 8, we are closest to Pennsylvania, which on the 19th day of the epidemic had 10 thousand infected and the period for doubling was 5 days. In the United States since day 32 (300 thousand infected) there is 7 days for doubling.
   Statistical zero - is the day when the number of cases exceeds 50. For the US, this is February  24, and for Russia, is March 14, 2020.
  According to the current trend, there should be about 18,500 COVID-19 infected people in Russia on April 13 (the month from statistical zero). By this time there will be enough data to forecast the date of the trend reversal and estimate the total number of infected people.
in Russian

When will this disease go away? part 2

                                                                    - Please  tell me, when will this disease go way?

 - According to the news, only in 2036 
(Joke)

   Now about Russia, where rulers also chose the Chinese version of the fight against infection. A little information about the new flu: symptoms of COVID-19 infection resemble those of seasonal flu (dry cough, fever,  weakness). It is believed that this virus is much more virulent. Let's calculate. R0 (basic reproduction number or how many zero patient infected:  

• influenza   1.4-2.8,
• CAVID-19  1.4-3.9,
• Measles     12-18. 

But this information is not enough to predict the epidemic, you need to know the serial interval (the time between infections). For  "Spanish flu"  it is 3 days and 5 days for COVID-19. The mortality  of  the  "Spanish flu" in 1918-1919 was 5-10%, for  Corona-virus  is 0.5 (if treated), and the same 5-8% if not treated.  On average , get sick  COVID-19 for 25 days, or die after 18 day of illness.

When will this disease go away? part 1

Epigraph. I opened social networks,
and I was surprised: why so
many virologists in my friends list ? Decent 

political scientists. they were after all. 

I think that the war will end in 3 months. But the number of corpses and the state of the economy in different countries will demonstrate the true IQ of their leaders. In the fight against COVID-19, 99% of countries chose the Chinese version of enhanced social distancing, ideally-locking in quarantine (from ital. quaranta — "forty"). each family in their own apartment. Taking into account the last statement of W.Putin quarantine in Moscow (41 days, March 21-April 30) will take on its original meaning. The United States, which is half a month ahead of Russia in the phase of the epidemic, has chosen the option of a state of emergency that is in effect throughout the country. Each state has its own implementation details: for example, in California, residents are ordered to stay at home, public meetings are prohibited, kindergartens, schools, bars, restaurants, and most stores are closed. At the same time, no one closes parks, prohibits people from Cycling or taking walks. Taking these measures into account, D. Trump's advisers predict the peak of the epidemic on April 15.

The total number of victims is expected to be 100-240 thousand. (without an emergency, these figures could reach 1.5-2.2 million). 

As of April 1, 216,000 people were infected and 5,100 died in the United States.

It is clear that in this version of the fight against the virus, the economy is sacrificed. A more balanced approach was chosen by the leadership of Sweden and Belarus. The Swedish government supported the strategy of the public health Agency, developed by epidemiologist Anders Tegnell. The scientist believes that a rigid quarantine is not needed, because long-term infection can be defeated either through universal vaccination, or as a result of  herd immunity - limited method of infection, providing a way to slow the spread and reach as many people. In Sweden, there are almost no restrictions, there are businesses, restaurants, schools and shops. There are only recommendations: if possible, switch to remote work, avoid contact with the elderly, and observe hygiene.

The number of deaths due to COVID-19 infection in the Scandinavian countries as of April 1, 2020:

Original text is  here.                      To be continued ...