Before revision:  We point out that, apart from R_0, an important quantity is the largest eigenvalue of the linearized dynamics which provides a more complete understanding of the disease progression  both pre- and post- intervention  and explains observed data .
After revision:  We point out that, apart from R_0, an important quantity is the largest eigenvalue of the linearized dynamics which provides a more complete understanding of the disease progression both pre- and post- intervention , and explains observed data .