Epidemic analysis of COVID-19 in China by dynamical modeling

Liangrong Peng; Wuyue Yang; Dongyan Zhang; Changjing Zhuge; Liu Hong

To this end, we firstly prefix the latent time γ −1 , which is generally estimated within several days 5, 33, 34 . And then for each fixed γ −1 , we explore its influence on other parameters (β = 1 nearly unchanged), initial values, as well as the population dynamics of quarantined cases and infected cases during best fitting. From Fig. 3a -b, to produce the same outcome, the protection rate α and the reciprocal of the quarantine time δ −1 are both decreasing with the latent time γ −1 , which is consistent with the fact that longer latent time requires longer quarantine time. Meanwhile, the initial values of exposed cases and infectious cases are increasing with the latent time. Since E 0 and I 0 include asymptomatic patients, they both should be larger than the number of quarantined cases. Furthermore, as the time period between the starting date of our simulation (Jan. 20th) and the initial outbreak of COVID-19 (generally believed to be earlier than Jan. 1st) is much longer than the latent time (3-6 days), E 0 and I 0 have to be close to each other, which makes only their sum E 0 +I 0 6 All rights reserved. No reuse allowed without permission.