It’s the question on every family’s mind: When will it be safe to send kids back to school? The answer hinges in part on what science shows about the virus’ impact on children and adolescents. 

“The virus is following certain rules,” says Yvonne Maldonado, MD, a professor of pediatric infectious diseases and of health research and policy at Stanford Medicine. “It takes time to see a pattern and to feel comfortable with it.”

On this episode of School’s In, Maldonado joins Stanford Graduate School of Education Dean Dan Schwartz and Senior Lecturer Denise Pope to talk about what research suggests about COVID-19 in children—including the age at which masks become a useful intervention, and what she recommends for parents if they learn that someone in their child’s classroom has tested positive for COVID-19.

In determining when to reopen schools, pay attention to the local rate of infection, Maldonado says. “You really want to have a stable rate of infection, preferably slowing down, before you start bringing people back.”

If the prevalence rate is in the range of 7 to 10 percent in your community, “that’s probably not a safe way to go,” she says. “But you can at least start the process of thinking how to move in that direction.”

When they do return to the classroom, Maldonado differs with some leading advisory groups by not recommending masks for younger children. “In the hospital, we don’t assume that a child under 10 will wear a mask or wear it properly,” she says.

What’s more, she says, data currently indicate that young children are less likely to transmit the disease than older children or adults. “But we don’t understand why that might be. There are many theories out there, biological as well as behavioral.”

You can listen to School's In on SiriusXM, Apple Podcasts, Google Podcasts, Spotify, Stitcher and Soundcloud.