Figure 1From: A dynamic optimal control model for COVID-19 and cholera co-infection in YemenSchematic diagram of the compartmental cholera-COVID-19 co-infection model. Please note that \(f_{1} = ( 1- u_{1} ( t ) ) A ( t ) + ( 1- u_{2} ( t ) ) I_{1} ( t )\), \(f_{2} = \alpha _{c} ( t ) I_{2} ( t ) + \frac{\beta B}{K_{B} +B} ( 1- u_{4} ( t ) )\) and \(f_{3} = rB ( B-b ) ( 1- \frac{B}{k} )\) in the flow chartBack to article page