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 have 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 in Indonesia and the state of Michigan in the USA, where laboratory testing capacities are 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 public measures. (C) 2021 ISA. Published by Elsevier Ltd. All rights reserved.

Automated summary

A new compartmental epidemic model is proposed in this study, which takes into account the probable cases with symptoms but no confirmatory laboratory testing. The model is proven to be well-posed, and an explicit expression for the basic reproduction number is provided. The model is combined with an extended Kalman filter to estimate the time-varying effective reproduction number of COVID-19 in West Java province, Indonesia and the state of Michigan, USA, where laboratory testing capacities are limited. The results show that the value of the reproduction number is higher when the probable cases are considered.