Harvard University researchers say an on-again, off-again approach to social distancing could be a more effective strategy to avoid overwhelming hospitals and to build herd immunity against the novel coronavirus — but other experts aren’t so sure.
An April study, conducted at Harvard University’s T.H. Chan School of Public Health, championed intermittent social distancing — measures that are periodically reimposed when cases reach certain levels.
Christine Tedijanto, a PhD student who co-authored the study, told Global News it will take at least two more years to reach “sufficient levels of population immunity for the disease to stop spreading.”
According to the researchers’ modelling, as long as social distancing occurred between 25 per cent and 75 per cent of the time, the world could both build immunity and keep the health-care system from overloading.
“If we believe that COVID-19 will confer at least some immunity to the infected, for some period of time, then it means that those that have already gotten the infection are protected,” she said, noting that the exact immunity level remains under research.
“Then, we also slow that spread enough that everyone that does have severe disease is able to be properly cared for by the health-care system.”
Dr. Todd Coleman, an epidemiologist and assistant professor in health sciences at Wilfrid Laurier University, called the staggered approach to social distancing a “gamble” at best.
He said Harvard’s modelling assumes that immunity takes hold for long periods of time, but the science behind that remains unclear.
Instead of flattening or prolonging the COVID-19 curve, intermittent social distancing would see the virus continue in ups, downs and spikes. People would develop antibodies, Coleman said, but he added, “we don’t know if these antibodies are protective against re-infection.”
There’s also a trade-off that comes with herd immunity.
“If we try to maximize infections to allow for herd immunity, that also means that the likelihood of people dying quickly is higher as well,” he said.
Periodic surges could also overburden the health-care system, he added.
Colin Furness, an infection control epidemiologist and assistant professor at the University of Toronto, said intermittent social distancing is an attractive option, but one that “assumes that you have closed the door” on eliminating community spread altogether.
He said opting for intermittent social distancing is “very much a philosophical decision about how you prioritize health and wealth.”
Furness added he would not support the distancing strategy, adding that a “far better” approach is to try to eliminate community spread, which would minimize the number of infections and deaths in each country.
“When we in Canada are saying we want to have social distancing and stomp out this infection, what we’re really saying is health comes first. We need to make this virus go away and we’re willing to throw a lot of wealth under the bus in order to protect population health,” Furness said.
“The thinking behind intermittent social distancing is to reverse that and say, actually, we can’t allow health to get in the way of wealth.”