This research aims to suppress the birth rate and increase the mortality of mites to reduce the infection risk. We used an approach using optimal control to reduce the population of mites. The control intervenes by reducing the birth and increasing the mortality of mites and by reducing contact with mites and rodents. The basic reproduction number R0 was obtained, and the sensitivity to each parameter was investigated. We applied Pontryagin’s maximum principle to explore an optimal control strategy to minimize the mite population. Controls were interventions with insecticides. Insecticide spraying to reduce the mite population should be conducted during the initial stages, and control to reduce contact with the host should be continuously implemented. We investigate the optimal control and the cost calculated using the modified average cost-effectiveness ratio (mACER). Both the optimal control and the cost of mACER were better for A1 = 0.1, A2 = 3 than A1 = 0.01, A2 = 0.1 for each control.