Evaluating the effect of public health intervention on the global-wide spread trajectory of Covid-19

Zixin Hu; Qiyang Ge; Shudi Li; Li Jin; Momiao Xiong

fully comprehensive intervention and assigned 1 to the intervention variable. We assigned 0 to the intervention variable if there was no intervention. The weights between 0 and 1 were assigned to the intervention variable for the different degrees of interventions. The values that were assigned to the intervention variable was called weight. Taking time for intervention into account, we considered four comprehensive intervention scenarios. The first intervention scenario was to start intervention on March 9, 2020 and the weight was 1. The second intervention scenario was to start limited intervention on March 9 (the weight was 0.5) and one week later to start complete intervention (the weight was 1). The third intervention scenario was that in the first week (starting on March 9) no intervention was taken (the weight was 0); in the second week, take limited intervention (the weight was 0.5); and after the third week, take full intervention (the weight was 1). The fourth intervention scenario was that in the first one week, no intervention was taken (the weight was 0), in the next three weeks, limited intervention was taken (the weight was 0.5), and after the fourth week, full intervention was taken (the weight was 1). We investigate how the degree of intervention and starting intervention time determine the peak time and case ending time, the peak number and maximum number of cases and forecasting the peak and maximum number of new and cumulative cases in more than 100 countries across the world. The analysis is based on the surveillance data of confirmed and new Covid-19 cases in the world up to March 8, 2020.