Comparison of the transmission of COVID -19 between Hebei and Heilongjiang in early 2021

ABSTRACT

Objective To compare the diversity of transmission of COVID -19 in Hebei and Heilongjiang Province in early 2021, and to provide theoretical support for the formulation of prevention and control strategies for COVID -19. Methods A dynamical model with staged control strategies was constructed based on the number of existing asymptomatic cases, the number of existing confirmed cases and the cumulative number of removed cases in Hebei and Heilongjiang at the beginning of 2021. Parameters of the model were estimated by the nonlinear least square method. Sensitivity analysis was used to explore the impact of key parameters on the peak number and peak time of existing confirmed cases in the two regions. We respectively analyzed the influence of the change for the number of initial contacts, the probability of initial contacts, the relative infectivity correction factor of the latent and the composition ratio of the symptomatic infection on the number of existing asymptomatic cases, the number of existing confirmed cases and the number of cumulative cases in the two regions. Results The model fitting results of the two regions were good. Compared the results of Hebei with those of Heilongjiang, there was a larger proportion of asymptomatic infected persons. When the number of initial contacts, the probability of initial contacts, the relative infectivity correction factor of the latent and the composition ratio of the symptomatic infection separately decreased by 10%, the average decrease for the peak number of existing asymptomatic and existing confirmed cases, and the cumulative removed cases in Heilongjiang were more than those in Hebei. Conclusions In early 2021, the transmissions of COVID -19 in Hebei and Heilongjiang were significantly different. In particular, the impact of control measures on the development of the epidemic is different in different areas. © 2023, Publication Centre of Anhui Medical University. All rights reserved.