Before revision:  Furthermore, these policies, while not eliminating the virus , can nevertheless be sustained over long periods of time, until a vaccine or treatment becomes available .
After revision:  Periodicity confers (i) predictability, which is essential for economic sustainability, and (ii) robustness, since lockdown periods are not activated by uncertain measurements over short time scales. In turn -- while not eliminating the virus , can nevertheless be sustained over long periods of time, until a vaccine or treatment becomes available .