A time delay model for COVID-19

In this paper, using time delay differential equations, a mathematical model for viral disease COVID-19 is introduced. Two time delays are considered. T-1 is the time interval between infection and the onset of symptoms and T-2 is the reinfection time interval in recovered individuals. As fallow, the stability in disease free equilibrium point and stability in endemic equilibrium point when the time delays are zero is investigated. Finally, the solution curves when the time delays are nonzero are drawn.