Northeastern researchers are part of the network of teams creating models to advise the Trump administration on the COVID-19 outbreak in the United States, White House officials said Tuesday.
They said data from the models formed the basis of President Donald J. Trump’s decision to extend the “social distancing” guidelines he set two weeks ago, through the end of April.
Deborah Birx, the White House coronavirus response coordinator, said that the modeling estimates provided by Northeastern’s Network Science Institute and researchers from several other universities had made it possible to “see what these mitigations could do—how steeply they could depress the curve.”
“In their estimates, they had between 1.5 million and 2.2 million people in the United States succumbing to this virus without mitigation,” Birx said. “Yet through their detailed studies and showing us what social distancing would do—what would happen if people stayed home, what would happen if people were careful every day to wash their hands and worry about touching their faces—what an extraordinary thing this could be if every American follows these.”
The Northeastern team, led by Sternberg Distinguished University Professor Alessandro Vespignani, along with groups from Harvard, Columbia, and Imperial College London, showed that, with the appropriate measures, the U.S. could be looking at between 100,000 and 200,000 deaths in the coming months, instead of millions. These are the numbers that White House officials said they are preparing for, although they hope to do even better.
The researchers “are modeling how the spreading of COVID-19 will be affected by different kinds of mitigation strategies,” said Kate Coronges, the executive director of the Network Science Institute. “They’re able to inform decision makers on what kinds of social distancing or travel ban policies would have the best chance of reducing transmission.”
Northeastern’s model is incredibly complex. In addition to accounting for the disease’s incubation period, how contagious it is, and the method of transmission, the model also needs to incorporate factors that influence human behavior, such as transportation, social interactions, and the availability of medical resources in different areas.
The models are constantly being updated to include newly acquired data about the transmission, contagiousness, incubation, and virulence of the virus. The team has also incorporated mobility data to increase the accuracy of their models.
“The team is using mobile phone data to track changes in people’s movement to better understand the effects of various social distancing policies across the U.S.,” Coronges said. “This allows them to quantify ‘social distancing’ measures with much greater accuracy and granularity.”
Vespignani’s team began refining its models long before the first mentions of a “novel coronavirus” appeared in the news in late 2019. In collaboration with researchers from the University of Florida, the Fred Hutchinson Center, the ISI Foundation, and the Fondazione Bruno Kessler, they worked previously on assessing the potential international spread of Ebola during the 2014 outbreak, as well as modeling the spread of the Zika virus in 2017.
These diseases all spread in different ways—Ebola requires direct contact with fluids, Zika is transmitted via mosquitoes, and COVID-19 spreads through droplets—but understanding their spread requires understanding the behavior of human beings. And understanding what happens when that behavior changes.
“They come up with a model of how the disease should spread through a population given all the known parameters about the virus, and then they can build very specific mitigation scenarios into the models,” Coronges said. “What happens when schools are closed? What if you close schools for two weeks or four weeks and then reopen them? What happens if travel is restricted from specific regions? What is the effect if you apply these policies to some cities but not others? So they are able to estimate the effects of the different policies that the local and federal government are considering.”