Stochastic COVID-19 SEIQ epidemic model with time-delay

In this work, we consider an epidemic model for corona-virus (COVID-19) with random perturbations as
well as time delay, composed of four different classes of susceptible population, the exposed population, the
infectious population and the quarantine population. We investigate the proposed problem for the derivation
of at least one and unique solution in the positive feasible region of non-local solution. For one stationary
ergodic distribution, the necessary result of existence is developed by applying the Lyapunov function in the
sense of delay-stochastic approach and the condition for the extinction of the disease is also established. Our
obtained results show that the effect of Brownian motion and noise terms on the transmission of the epidemic
is very high. If the noise is large the infection may decrease or vanish. For validation of our obtained scheme,
the results for all the classes of the problem have been numerically simulated.