Before revision:  It is shown that the quantity that can be the most robustly estimated from the normalized data, is the timing of the maximum and timings of the inflection points of the proportion of infected individuals  .
After revision:  It is observed that the basic reproduction number and the mean duration of the infectious period can be estimated only in cases where the spread of the epidemic is over (for China and South Korea in the present case). Nevertheless, it is shown that the timing of the maximum and timings of the inflection points of the proportion of infected individuals .