4:58 p.m. ET, June 4, 2020
Computer modeling shows social distance strategies can keep curve flat
From CNN’s Andrea Kane
An aerial view shows painted circles in the grass to encourage people to social distance at Washington Square Park in San Francisco on May 22.
Josh Edelson/AFP/Getty Images
Three different social-distancing strategies when reopening after lockdown can be effective in curbing the spread of Covid-19, according to a group of British and Swiss researchers who used computer simulations to compare the effects of each.
Social distancing – maintaining physical distance and reducing social interactions — has been a key component of most governments’ attempts to reduce the spread of Covid-19. It’s been shown to help slow the rate of transmission and the growth rate of infection (aka: flattening the curve).
But complete or near-complete lockdowns have a down side: negative social, psychological and economic consequences. The new study, published in the journal Nature Human Behavior, evaluates three more moderate contact-reduction strategies to determine how well they keep the curve flat after a lockdown.
The three strategies are: contact with only similar people (for example, people who live close to each other geographically or are members of the same organization); strengthening contact within communities (for instance, where people only meet with friends when they have many friends in common); and repeatedly interacting with the same people in “bubbles” (limiting interactions to a few, repeated individuals).
The researchers, who ran their models based on 500 to 4,000 people, found that all three slowed the spread of Covid-19, compared both to no social distancing and to non-strategic social distancing, where individuals randomly reduced interactions. Among the three, interacting in social bubbles was the most effective.
Because most people need to interact across multiple social groups, the researchers also tested the effectiveness of combinations of two or all three of the strategies. They found that combined strategies were as effective as single strategies and that all worked better than random social distancing or no social distancing at all.
“Simple behavioural rules can go a long way in keeping the curve flat,” they concluded.
“As the pressure increases throughout a pandemic to ease stringent lockdown measures, to relieve social, psychological and economic burdens, our approach provides insights to individuals, governments and organizations about three simple strategies: seeking similarity; strengthening interactions within communities; and repeated interaction with the same people to create bubbles.”