  Here, we focus on the data analysis of the growth of epidemic spread of
Covid-19 in countries where different policies of containment were activated.
It is known that the growth of pandemic spread at its threshold is exponential,
but it is not known how to quantify the success of different containment
policies. We identify that a successful approach gives an arrested phase regime
following the Ostwald growth, where, over the course of time, one phase
transforms into another metastable phase with a similar free energy as observed
in oxygen interstitial diffusion in quantum complex matter and in
crystallization of proteins. We introduce the s factor which provides a
quantitative measure of the efficiency and speed of the adopted containment
policy, which is very helpful not only to monitor the Covid-19 pandemic spread
but also for other countries to choose the best containment policy. The results
show that a policy based on joint confinement, targeted tests, and tracking
positive cases is the most rapid pandemic containment policy; in fact, we found
values of 9, 5, and 31 for the success s factor for China, South Korea, and
Italy, respectively, where the lowest s factor indicates the best containment
policy
