Since the outbreak of COVID-19, the severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) genome is still mutating. Omicron, a recently emerging
virus with a shorter incubation period, faster transmission speed, and stronger immune
escape ability, is soaring worldwide and becoming the mainstream virus in the COVID-
19 pandemic. It is especially critical for the governments, healthcare systems, and
economic sectors to have an accurate estimate of the trend of this disaster. By
using different mathematical approaches, including the classical susceptible-infectedrecovered (SIR) model and its extensions, many investigators have tried to predict the
outbreaks of COVID-19. In this study, we employed a novel model which is based
upon the well-known susceptible-infected-removed (SIR) model with the time-delay
and time-varying coefficients in our previous works. We aim to predict the evolution
of the epidemics effectively in nine cities and provinces of China, including A City, B
City, C City, D City, E City, F City, G City, H City and I Province. The results
show it is effective to model the spread of the large-scale and sporadic COVID-
19 induced by Omicron virus (Omicron-COVID-19) by the novel non-autonomous
delayed SIR compartment model. The significance of this study is that it can
provide the management department of epidemic control with theoretical references
and subsequent evaluation of the prevention, control measures, and effects.