Nonpharmaceutical Interventions

Four Stylized Facts about COVID19 - Study of Nonpharmaceutical Interventions

August, 2020


We document four facts about the COVID-19 pandemic worldwide relevant for those studying the impact of non-pharmaceutical interventions (NPIs) on COVID-19 transmission.

First: across all countries and U.S. states that we study, the growth rates of daily deaths from COVID-19 fell from a wide range of initially high levels to levels close to zero within 20-30 days after each region experienced 25 cumulative deaths.

Second: after this initial period, growth rates of daily deaths have hovered around zero or below everywhere in the world.