As the United States begins its phased reopening, some experts warn that the country is easing social distancing too quickly—and point to a more modest approach, known as "double-bubbling," that other countries have successfully deployed, Sigal Samuel reports for Vox's "Future Perfect."

10 takeaways: What America can learn from the world's coronavirus response

What is 'double bubbling?'

Governments around the world are allowing residents to form "double bubbles"—social groups comprised of two households that "make a pact to hang out with" only "each other" and practice social distancing with everyone else, "Future Perfect" reports.

The idea of the double bubble is to reduce social isolation before fully reopening the country, Vox reports.

New Zealand, which for now has successfully lowered new coronavirus cases, was one of the first countries to use the strategy. A few European countries, including Germany, and Canada also have implemented the strategy as part of their reopening plans.

For instance, in Canada, New Brunswick permitted its population to double bubble beginning on April 14, followed by Newfoundland and Labrador on April 30 and Nova Scotia on May 15. Weeks later, the provinces—which had low case numbers prior to being allowed to double bubble—still have not seen a rise in daily new Covid-19 cases.

"In the last few weeks, there has not been a rise in cases—in fact the opposite is true," Isaac Bogoch, an infectious disease specialist at Toronto General Hospital, told "Future Perfect." "This is a very smart and creative approach to the early phases of lifting the public health restrictions we're living under."

Should the US consider double bubbling?

Now, some experts are beginning to question whether the United States should consider allowing double bubbling as part of a more gradual reopening plan. Those experts, "Future Perfect" reports, argue that it would be safer to allow families to ease social distancing to connect with one other household than to begin opening restaurants and other public spaces, which many states have already begun doing. 

Julia Marcus, an infectious disease epidemiologist at Harvard University, said, "If we don't provide harm reduction guidance that acknowledges the risks people are already taking and in some cases need to take, we are missing an opportunity to mitigate risk." She added, "Instead, people might choose to see lots of different people one after another, with more potential to expose themselves or others."

However, Marcus said the approach should be applied regionally. For instance, she said the approach should not be implemented in communities like New York City that still have a high transmission rate of the virus, but it could be viable option for other areas.

"Assuming that a region is doing well in terms of new cases and the amount of community spread, this seems to me like a perfect example of how harm reduction can be applied to social distancing," Marcus said, adding, "I think this is something we need to be considering."

But other experts have warned double bubbling is not as safe as it might seem.

Carolyn Cannuscio, a social epidemiologist at the University of Pennsylvania, in April told "Future Perfect" that having a small, "closed circle" still places those households at risk because they could contract the virus while running necessary errands, like going to the grocery store. The households would also have to consistently stick to a strict set of social distancing rules outside of the circle, which Cannuscio said could be difficult to follow.

"All of us as human beings are flawed," she said. "We set out with great intentions but ... it's complex for human beings to actually follow through on those kinds of promises" (Samuel, "Future Perfect," Vox, 6/2; Samuel, "Future Perfect," Vox, 4/28).