The emergence and rapid spread of novel Covid-19 coronavirus in early 2020 spurred numerous accelerated efforts to develop a vaccine. At the time it was not clear how effective these vaccines needed to be to slow or stop the pandemic. The U.S. Food and Drug Administration (FDA) set 50 percent or greater as the target efficacy for the vaccines, but it was not clear then what efficacy levels would be needed to return to normal.

To offer guidance, researchers from Public Health Informatics, Computational, and Operations Research (PHICOR) at the CUNY Graduate School of Public Health and Health Policy (CUNY SPH) worked with the National School of Tropical Medicine and Lundquist Institute at Harbor-UCLA Medical Center to develop a computational model of the U.S. population that simulated the spread and impact of the Covid-19 coronavirus. The model served as a virtual laboratory to test the effect of Covid-19 vaccines with a variety of efficacies, administered in different ways and times to different proportions of the population. This work was deemed paper of the year in 2020 by the American Journal of Preventive Medicine on June 17.