Wilensky reported his lessons from severe covid-19 experience¹. In science, an objective view is important for solving a problem. In the world, many nations have different individual past and on-going lessons through the covid experience. From the viewpoint of human perspective, the number of deaths due to the covid pandemic should be used for grading the success of individual policies. Successful policies can provide a pleasant lesson to their citizens while the unsuccessful policy can bring harsh lessons to them. According to the worldometer, the successful policy based on digital fence using smart phones is implemented by Taiwan where isolating-all-at-risk strategy has been used². The successful policy was deduced by their past lessons from SARS³. Taiwan has cumulative seven deaths due to the covid-19 with a population of 23.8 million. Since we have no vaccine and no effective therapy against the covid-19, isolating-all-at-risk in real time is one and only one effective policy against the pandemic. The US has an enough capability to perform the best similar policy for mitigating the pandemic.

References:

1.October 22, 2020 N Engl J Med 2020; 383:e96 DOI: 10.1056/NEJMp2023204

2. https://www.loc.gov/law/help/coronavirus-apps/taiwan.php

3. WHO, Severe Acute Respiratory Syndrome (SARS),