Is Covid-19 man-made after all?

I read a new preprint by Prashant Pradan et al, “Uncanny similarity of unique inserts in the 2019-nCoV spike protein to HIV-1 gp120 and Gag”

https://www.researchgate.net/publication/338957445_Uncanny_similarity_of_unique_inserts_in_the_2019-nCoV_spike_protein_to_HIV-1_gp120_and_Gag

            The paper claims that the spike protein of Covid-19 has developed from the spike protein of SARS and that there are four inserts in the spike protein of Covid-19. All four insets are preserved in all Covid-19 samples (meaning that they are new) and they are all similar to parts of the corresponding protein in HIV-1. The authors conclude that this cannot be a coincidence. It is not likely to be a result of random mutations. The authors mention that viruses can change RNA sequences, but it would be quite improbable for a working virus to appear in this way. It does look like Covid-19 is a bioweapon. The mandatory debunking paper is here:

Chuan Xiao et al: HIV-1 did not contribute to the 2019-nCoV genome https://www.researchgate.net/publication/339260776_HIV-1_did_not_contribute_to_the_2019-nCoV_genome

            This debunking paper says it all in the title. No HIV-1 virus parts in Covid-19. This link also has a full paper and I briefly read it. The authors admit that there are four insertions in Covid-19, but they argue that they are not necessarily from HIV-1. They explain that three of the four insertions are in the bat virus. This of course is a fairly good argument against the insertions being man-made. If so and if Covid-19 is man-made, then the bat virus is also man-made and an intermediate virus from bird SARS to Covid-19. The debunking paper does not discuss and discard this possibility, but when you debunk something, you should correctly debunk the claim – go through all possible arguments and debunk them. The debunking paper, as it is now, is sadly lacking in these respects, even though it may well be correct in wider sense.

There was a recent paper by Azra Ghani et al from Imperial College London stating that the mortality rate of Covid-19 is only 0.66% and the reason that the mortality rate appears higher is that all cases have not been found. I very much doubt this result for the following reasons.

            The doubling time of infected does not depend on the portion that is tested. From Chinese data the doubling time is about 7 days. The growth of virus infections is exponential before any measures to limit the epidemic are applied. Thus, the series of daily new infections is geometric. In order to get the doubling time of 7 days the geometric series grows 10% each day: 1.1⁷= 1.9487, about 2. By German tests a person infected with Covid-19 is unlikely to infect other people after 10 days and is most infectious in the day 4. We can assume that an infected person is removed from the pool of infectious people after 10 days. Thus, a time series taken every ten days gives the growth of the epidemic. In ten days one infected person infects 1.1¹⁰-1=2.6-1=1.6 new people. According to Chinese data the average time people who died from becoming infected to death was 29 days. The average time for recovery may be two weeks, but at least in the early stages of the epidemic infected people were not declared totally recovered before about one month. For this reason we can set the average time for recovery to be the same as the average time to die. For simplicity, let us round 29 days to 28=4*7. Then there are 4 doublings of the number of infected in the time a person has either died or recovered from the virus. The sum of dead or recovered should then be 2^-4=1/16 of the number of infected as long as the epidemic is in the exponential stage. There remains the question of what is the mortality rate. This depends on how much the number of tested infections differs from the real number of infections.

            Norway, Germany, South Korea and Israel have tried to test most of the suspected infections. In 1. April 2020 Israel is in the geometrically growing stage. The number of infected is 5,591 and the number of dead is 20. This gives 0.36% as the mortality rate if counted by dividing these two numbers. In Israel the growth has been a bit higher than 10% daily (this figure depends on the culture): in 20 days the number of infected has risen from 1 to 5,591. As 5,591=1.539²⁰, in 28 days the number of infections grows to 17.5. Instead of 16, the number of infected is 17.5 larger than the sum of dead or recovered. The sum of dead or recovered is thus 5,591/17.5=319. The mortality rate is thus 20/319=0.063, 6.3%. We get very similar estimated also from Germany and South Korea from the time when the epidemic in these countries was growing exponentially.

            We can confirm this estimate from Finland. During the period 3. March 2020 to 12. March 2020 all infections were tracked in Finland. Finland changed the measurement strategy in 12. March 2020: after that time only a fraction were tested. Finnish infection data, though the number of cases is small, suggests that the portion of tested cases since 13. March 2020 is about 1/4 of all cases. (Especially, it is unlikely to be 1/20 to 1/30 of all cases, as Finnish health authorities have estimated.) In the last few days the number of infected in Finland has decreased, but not so much that it would much affect the result. In 1. April there are 1,418 tested Covid-19 cases in Finland and 17 dead. Assuming that the mortality rate is 5% and the doubling time is 7 days, the figure 17 dead suggests 17*(16/0.05)=5,440 infected. It is 3.85 times the number of tested fitting well with the plot of infections before and after 12. March 2020.

There is an even better confirmation, from Iceland. Iceland has made mass tests and found that half of the carriers show no symptoms. This fits nicely: half show symptoms, half of those who show symptoms are tested in Finland, so the real number of infected is four times the number of tested positive. Again, it is not 20-30 times as much.

            In 1. April 2020 the figures are 859,800 infected, 42,340 dead and 178,335 recovered in the whole world. Let us subtract China and South Korea as in these countries the epidemic has been taken in control and it not growing. Excluding these countries there are about 770,000 infected, 39,000 dead and 96,000 recovered.

            The ratio of infected to dead or recovered is 770,000/135,000=5.7, which is quite far from the expected about 16. There are two reasons for this. The first is that the real recovery time is below 28 days. In the beginning of the epidemic infected were not confirmed totally recovered for a long time after their symptoms should have disappeared, but this is not any more the case. The true (or recommended) recovery time is two weeks, and three days are added for testing of recovery. Thus, the average recovery time is 17 days. In 1. April 2020 the dead are 19% of the total of dead or recovered. Thus, the average time for dying or recovering is 0.19*28+0.81*17=19 days. From this 1.0959¹⁹=5.7. We notice that the daily growth is not 10%. It is 9.59%. This is correct since the epidemic having slowed in several countries (Italy, Spain, Germany, etc.)

            Using the figure 5.7 as a multiplier to get the number of infected from the number of dead or (real) recovered and using 5% as the real mortality rate (instead of the apparent mortality rate of 19%=42,340/220,675 or  29%=39,000/135,000 when China and South Korea are excluded) we get the real number of infected in 1. April as 39,000*5.7/0.05=4.4 million. It is 5.7 times higher than the number of tested infections.

            The mortality rate is thus 5% for this most probably man-made virus. If all cases are found, the mortality rate is probably 2.5%. Where it came from I do not guess. From a country with an advanced bioweapon program. Probably it escaped by a mistake, but maybe not. Why would anybody want to release such a killer virus? Maybe one should think of this: herd immunity for a virus with 5% mortality is insanity and will not be made. Therefore the only way to stop this virus is quarantine, which stops the whole economy. Causing a world depression is very harmful, but in all catastrophes there are those who gain. In one year there is a vaccine, but what happened to money?

The growth of the pandemic in different countries shows clear how cultures differ (there is some genetic contribution included, the personality trait introversion/extroversion and also obedience to rules). For a virus the number R0 means the number of people an infected person infects. In the analysis above it was 1.4 if the growth is 10% a day. We can see in

https://www.worldometers.info/coronavirus/

that for Germanic (German/Scandinavian) speaking countries the growth is usually slower than for Mediterranean countries. It is also low for East Asians. The notoriously introverted Finns may just manage to stop this epidemic just by not meeting anybody though the rules are not at all strict. The Slavic (much more friendly) Poles may also manage, but with very stringent rules. But, the simpler explanation is that countries that have imposed a lockdown manage to slow or stop the epidemic. Yet, there is some difference in the effect of the lockout. France has strict rules, but it still does not seem to reduce the daily increase below 7% (as it must if the epidemic should be stopped).