In all Countries the political decisions aim at the Covid-19 spreading reduction and at reaching an almost stable configuration of coexistence with the disease, where a small number of new infected individuals per day is sustainable. In such a phase , the containment effort will be reduced in favor of a gradual reopening of the social life and of the various economical sectors and the evaluation of the possible infection regrowth should be very useful. Microscopic models, which take into account the details of the new social and economical conditions, would require a complex dynamics of the stakeholders .  We discuss a less detailed approach which, on the basis of the collected data  after few days from the beginning of the new phase, outlines different scenarios of the Covid-19 diffusion for longer time. The  method applies a time dependent carrying capacity, analogously to many macroscopic growth laws in biology, economics and population dynamics. The illustrative cases of Singapore, Italy and Sicily are analyzed.
In all Countries the political decisions aim to achieve an almost stable configuration with a small number of new infected individuals per day due to Covid-19. When such a condition is reached , the containment effort is usually reduced in favor of a gradual reopening of the social life and of the various economical sectors . However, in this new phase, the infection spread restarts and a quantitative analysis of the regrowth is very useful. We discuss a macroscopic approach which, on the basis of the collected data in the first lockdown, after few days from the beginning of the new phase, outlines different scenarios of the Covid-19 diffusion for longer time. The purpose of this paper is a demonstration-of-concept: one takes simple growth models, considers the available data and shows how the future trend of the spread can be obtained. The method applies a time dependent carrying capacity, analogously to many macroscopic growth laws in biology, economics and population dynamics. The illustrative cases of Singapore, France, Spain and Italy are analyzed.
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at the Covid-19 spreading reduction and at reaching
to achieve
R
of coexistence with the disease, where
with
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is sustainable. In such a phase
due to Covid-19. When such a condition is reached
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will be
is usually
D
and the evaluation of the possible infection regrowth should be very useful. Microscopic models, which take into account the details of the new social and economical conditions, would require a complex dynamics of the stakeholders
A
However, in this new phase, the infection spread restarts and a quantitative analysis of the regrowth is very useful.
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less detailed
macroscopic
A
in the first lockdown,
A
purpose of this paper is a demonstration-of-concept: one takes simple growth models, considers the available data and shows how the future trend of the spread can be obtained. The
R
Italy and Sicily
France, Spain and Italy