Waning Immunity and the Second Wave: Some Projections for SARS-CoV-2

This paper offers projections of future transmission dynamics for SARS-CoV-2 in an SEIRS model with demographics and waning immunity. In a stylized optimal control setting calibrated to the United States, we show that disease is endemic steady state its are characterized by damped oscillations. The magnitude oscillations depends on how fast immunity wanes. social distancing policy both curbs peak prevalence postpones infection waves relative uncontrolled dynamics. Last, perform sensitivity analysis respect duration immunity, fatality rate, planning horizon. (JEL I12, I18, J11)