Optimal strategies for controlling the MERS coronavirus during a mass gathering

A two-group model for Middle East Respiratory Syndrome Coronavirus (MERSCoV) is designed and used to assess the impact of quarantine of susceptible individuals and a hypothetical anti-MERS-CoV vaccine on the transmission dynamics of MERS-CoV within the two groups. The model undergoes a backward bifurcation, which is shown to arise due to the assumption that the hypothetical vaccine offers incomplete protection against infection. The model can have one or more endemic equilibria when the associated reproduction number exceeds unity. Uncertainty and sensitivity analyses are carried out to determine the effect of uncertainties in the parameter estimates of the model, as well as to determine the main parameters that drive the disease transmission process. The model is re-formulated as an optimal control problem, and the resulting model is used to evaluate the impact of various control strategies. Numerical simulations of the optimal control model suggest that if the cost of implementing quarantine and vaccination strategies are high, the two strategies can be administered optimally by using their maximum feasible (coverage) levels for a relatively shorter period of time (i.e., “hit-hard and hit-early”), and the coverage level then continuously decreased the next few days afterwards. Furthermore, a universal strategy, based on the combined use of uarantine and vaccination strategies, is shown to be more effective than the singular implementation of either the vaccination or quarantine strategy.