The United States' top pandemic advisor said Sunday that authorities were considering cutting social distancing rules to three feet (one meter), a move that would change a key tenet of the global fight against Covid-19.
Anthony Fauci, a world-respected figure during the coronavirus crisis, said experts at the Centers for Disease Control (CDC) were examining a Massachusetts study that found "no substantial difference" in Covid cases in schools observing six-foot and three-foot rules.
Asked on CNN's "State of the Union" show whether that meant that a three-foot separation was sufficient, Fauci replied, "It does, indeed."
While cautioning that the CDC was still poring over the new data and conducting tests of its own, he said its findings would come "soon."
The six-foot social distancing rule has been a widely-adopted global measure to prevent the spread of the coronavirus, along with mask-wearing and hand-washing.
School officials across the world are under enormous pressure to fully reopen as soon as safely possible, but many say the six-foot requirement makes it extremely difficult without adding portable classrooms or shortening the school day.
Many teachers unions have also insisted on six-foot distancing.
Policies on reopening schools and businesses have varied sharply across the US and around the globe as government try to balance quelling infections with a return to normal life.
The study led by the Beth Deaconess Medical Center in Massachusetts, surveying 251 school districts, found "no substantial difference in the number of cases of Covid-19 among either students or staff" between those observing the three- and six-foot rules when all wore masks.
The findings, published in the journal Clinical Infectious Diseases, add to a growing body of evidence that Covid-19 transmission rates are low in schools.
In another potentially significant finding, researchers found the rates of Covid-19 were lower in schools practicing masking than they were in the surrounding cities and towns.
A three-foot rule would have an enormous impact on prospects for fully reopening schools, offices and even public areas such as sports venues.
As the top school officials from Penfield, New York wrote in the journal Education Week, "The single biggest obstacle to fully reopening schools is the 6-foot distancing requirement."