Modeling the Comparative Impact of Individual Quarantine vs. Active Monitoring of Contacts for the Mitigation of COVID-19

Corey M Peak; Rebecca Kahn; Yonatan H Grad; Lauren M Childs; Ruoran Li; Marc Lipsitch; Caroline O Buckee

First, the serial interval and extent of presymptomatic transmission are important determinants of the effectiveness of interventions. The median reproductive number was 0.57 under individual quarantine and 1.55 under active monitoring in serial interval scenario 1 ( Figure 2 ) and 0.49 under individual quarantine and 0.54 under active monitoring, respectively, in scenario 2 ( Figure 3 ). For the shorter serial interval defining scenario 1, control ( ) was achieved only by R e < 1 individual quarantine in 84% of simulations, by either intervention in 12% of simulations, and in 4% of simulations neither active monitoring nor individual quarantine reduced in a high R e < 1 feasibility setting (Figure 2 ). The effectiveness of active monitoring is particularly sensitive to parameter sets with earlier onset of infectiousness relative to symptoms. When , for .2 R 0 = 2 example, remains below one unless the onset of infectiousness precedes symptoms by R IQ more than two days while has little tolerance for presymptomatic infectiousness (Figure 4) .