Oliver Ratmann - March 17, 2021

Oliver Ratmann, PhD, Faculty of Natural Sciences, Department of Mathematics Imperial College London, Age groups that sustain resurgent COVID19 in the US

Dr. Ratmann and his team researched the role of children in driving the spread of COVID-19, as well as the time when the number of COVID-19 infections would decrease due to age-prioritized vaccinations. Using population data collected from March to October 2020, including 8,676 observation days, 200,794 age-specific deaths, and locations from 38 states plus Washington D.C. and New York City, his team implemented a series of analysis from correlation matrices of contact tracing categorized by age brackets to age-specific death profile; and using Foursquare’s location technology that follows 10M individuals per day in the US, age-specific mobility trends could be visualized to model time-varying contacts. The results showed that the age groups which consistently had a viral reproductive number of greater than 1 were ages 35-49 and 20-34, accounting for 65% of COVID-19 infections; by contrast, children aging from 0-9 and 10-19 had a reproductive number that’s consistently less than 1, and their school re-opening was not associated with substantial increases in COVID-19 infections. Thus vaccinating under 20-year-olds would not be an efficient use of the limited vaccine supply to prevent deaths and maximize benefits among the older, higher-risk groups.