A Compartmental Epidemic Model Incorporating Probable Cases to Model COVID-19 Outbreak in Regions with Limited Testing Capacity

We propose a new compartmental epidemic model taking into account people who has symptoms with no confirmatory laboratory testing (probable cases). We prove well-posedness of the model and provide an explicit expression for the basic reproduction number (ℛ 0 ). We use the model together with an extended Kalman filter (EKF) to estimate the time-varying effective reproduction number (ℛ t ) of COVID-19 in West Java province, Indonesia, where laboratory testing capacity is limited. Based on our estimation, the value of ℛ t is higher when the probable cases are taken into account. This correction can be used by decision and policy makers when considering re-opening policy and evaluation of measures.