The Centers for Disease Control and Prevention is thinking about revising its recommendation to distance six feet in classrooms.

According to a Harvard study published last week, 3-foot gaps are just as effective as 6-foot gaps when it comes to preventing the transmission of COVID-19.

The study found no difference in COVID-19 transmissions in Massachusetts schools when students distanced three feet instead of the CDC-recommended six feet.

Students in the study were wearing masks.

The CDC isn't ready to revise its recommendations just yet, but its director says the agency is looking at the possibility. They are doing its own tests as more teachers get vaccinated. The World Health Organization already recommends a distance of one meter.