Before revision:  We find that are predictions are in good agreement with the real data from the beginning of the appearance of the COVID-19 , which is not the case for the logistic model that applies only to the few last days. By inserting the numerical values of the parameters, obtained by analysing the real data , into the differential equation we found the values of the days where the maximum values of the number of infected people by COVID-19 will be reached in Italy and Belgium .
After revision:  We find that are predictions are in good agreement with the real data from the beginning of the appearance of the COVID-19 , which is not the case for the logistic model that only applies to the last few days. We use our differential equation parametrized with experimental data to make several predictions, such as the date when Italy and Belgium will reach a peak number of COVID-19 infected people .