Lockdown # 1

 

4 Summary and discussion

This observational study, using a generalized phe-nomenological method based on official daily deaths records only, shows that full lockdown policies ofFrance, Italy, Spain and United Kingdom haven’t had the expected effects in the evolution of the COVID-19 epidemic. 

What were the expected effects?

Our results show a general decay trend in the growth rates and reproduction numbers two to three weeks before the full lockdown policies would be expected to have visible effects

.Comparison of pre and post lockdown observations reveals a 

counter-intuitive slow down in the decay of the epidemic after lockdown. 

Estimates of daily and total deaths numbers using pre-lockdown trends suggest that no lives were saved by this strategy, in comparison with pre-lockdown, less restrictive, social distancing policies.

 Comparison of the epidemic’s evolution between the fully locked down countries and neighboring countries applying social distancing measures only, confirms the absence of any effects of home containment. Evolution of the epidemic in Sweden however indicates that, in the absence of any social distancing measures, the epidemic’s decay may be subject to larger fluctuations. 

This work thus suggests that social distancing measures, such as those applied in the Netherlands and Germany, or in Italy, France, Spain, and United Kingdom before the full lockdown strategies, have approximately the same effects as police-enforced home containment policies.

So far, the reasons for the relatively regular decay of the epidemic remain largely unknown.

While social distancing efforts may contribute to it,

environmental conditions could as well have played a role

 (possible seasonality of the virus). 

There is no evidence to seasonality for Covid19

The group immunity hypothesis, 

though being unlikely

if the

reference fatality rates are correct, 

deserves a short discussion: 

computing the number of daily new cases from the number of daily deaths following Eq (2),and using a fatality rate of 1.7%, 

we forecast a ratio of infected population at the end of the epidemic of 1.4%, 3.0%, 3.2%, and 2.1% in France, Italy, Spain, and United Kingdom, respectively. 

The latter is obviously far from being able to yield any group

immunity. 

Under the rough assumption that 50 to 70% of the population needs to be infected to ensure group immunity, it is possible to compute an hypothetical fatality rate using Eq (2). 

We find that, if group immunity was responsible for the decay of the epidemic, the fatality rates would be of about

 0.05%, 0.10%, 0.11%, and 0.07% for the 50% hypothesis in France, Italy, Spain, and UnitedKingdom, respectively,

 and of 0.03%, 0.07%, 0.08%,and 0.05% for the 70% hypothesis. 

Obviously, this is only a gedanken experiment, 

which is far beyond the scope of this paper,

and only serological tests and further data analysis, once the epidemic

is completely instinct, will   allow to discriminate between the possible reasons for its decay.

As a concluding remark, it should be pointed out that, since the full lockdown strategies are shown to have no impact on the epidemic’s slowdown, one should consider their potentially high inherent death toll as a net loss of human lives.

I have no idea how they reach this conclusion.

This study was published on April 24

Italian lock down worked.

https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(20)30201-7/fulltext