Abstract For the purpose of analysing the Omicron pandemic, we build a novel SEIaIsIoHR mathematical model. The fundamental properties of the model is studied including Boundedness, Uniqueness and existence. The boundedness of the model’s solution is examined by solving the fractional Gronwall’s inequality using the Laplace transform method. Utilising the Picard-Lindelof theorem, we can verify the solution’s existence and uniqueness. The next-generation matrix is used to compute Ro (Basic Reproduction Number), which is significant in mathematically infectious diseases. It is demonstrated that the endemic and disease-free equilibrium solutions are both globally and locally asymptotically stable. We next looked at the parameters’ sensitivity analysis based on Ro. Moreover, the model is extended by employing an optimum control theory to explain the effects of certain control methods. Lastly, the numerical simulations are performed to validate the model.