Nightmares. Tantrums. Regressions. Grief. Violent outbursts. Exaggerated fear of strangers. Even suicidal thoughts. In response to a call on social media, parents across the country shared with NPR that the mental health of their young children appears to be suffering as the weeks of lockdown drag on.

Most U.S. states have canceled in-person classes for the rest of the academic year. This week in Senate testimony , Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, sounded a cautionary note on the prospect of reopening school buildings nationwide, even in the fall.

He pointed to the emergence of serious inflammatory illness in a handful of children. "We don't know everything about this virus, and we really better be very careful, particularly when it comes to children," Fauci said. He was responding to this comment by Sen. Rand Paul, Republican of Kentucky: "I think it's a huge mistake not sending our kids back to school."

Dr. Dimitri Christakis, one of the nation's most prominent pediatricians, agrees with Paul, who is a physician by training. Christakis, who directs the Center for Child Health, Behavior and Development at Seattle Children's Hospital, is the editor-in-chief of the journal JAMA Pediatrics. And in a new piece published in the journal, he argues that the risks to children's learning, social-emotional development and mental health need to be better balanced with the risks of spreading the coronavirus.

"I don't care if I die"

Sarah, a mom in Northern California, is one of many parents who responded to our query about how their children are handling the shutdown. She and her husband work in the tech industry and have two daughters. Their older daughter, Phoebe, turned 5 just as their area's stay-at-home orders went into effect. Her birthday party had to be postponed.

"She has happy moments and laughs about things and plays and gets excited," says Sarah (we're not using her last name to protect her daughter's privacy). But, she adds, Phoebe has also "started saying some things that were really freaking me out."

One day, Sarah says, she asked her daughter to be more careful on the stairs in their house. "And she got indignant and she was like, 'Why? It's my choice if I fall and kill myself.' "

Another day, Phoebe asked to join her mother on a trip to the post office. "I told her no. And she's like, 'Why? I don't care if I die.' "

Sarah asked, " 'Can you tell me more about that, please?' And she's like, 'Well, you have an extra kid [her baby sister, Hannah], and Hannah's a good kid and I'm a bad kid.' "

Sarah says she's lucky that she has been able to take administrative leave from her job to be with her daughters full time during the lockdown and that they have mental health coverage. But it has been difficult finding a therapist who can treat a young child over video chat.

"An imperative"

Christakis says the serious effects of this crisis on children like Phoebe have been overlooked.

"The decision to close schools initially, and now to potentially keep them closed, isn't, I think, taking the full measure of the impact this is going to have on children," he told NPR. "Not just the short term, but the long term."

The problem, Christakis says, isn't just learning loss, which is expected to fall particularly hard on low-income children with unequal access to distance learning. Recent research from a large testing association on the " COVID-19 slide " suggests children may return in the fall having made almost a third less progress in reading, and half as much progress in math, compared with what they would have in a typical school year.

Mental health and social-emotional development, Christakis argues, have been less discussed: "The social-emotional needs of children to connect with other children in real time and space, whether it's for physical activity, unstructured play or structured play, this is immensely important for young children in particular." A new study in JAMA Pediatrics, he says, documents elevated depression and anxiety among children under lockdown in China.

A third major risk, says Christakis, is child abuse. With schools closed and activities canceled, adults who are mandatory reporters, such as teachers, are less likely to catch wind of abuse or neglect. Hospitals around the country are reporting a rise in admissions for severe child abuse injuries and even deaths — a rise that coincides with lockdown orders. And a sex-abuse hotline operated by the Rape, Abuse & Incest National Network reported that half its calls in March came from minors, for the first time in its history.

In his editorial, Christakis calls for a panel made up of interdisciplinary experts to make school reopening a priority in the United States. "I think we should sort of reason backwards from the expectation that children do start school, that that's an imperative. And then how do we make that happen safely?"

Safety, of course, is the reason schools closed around the world in the first place. It's still considered very rare for children to become seriously ill from the coronavirus, but recently a handful of children have died from an inflammatory illness related to COVID-19, the disease caused by the coronavirus.

The science on children's role in spreading the virus is also a moving target. A new analysis of Chinese contact-tracing data in the journal Science, co-authored by Maria Litvinova, suggests that children are in fact less susceptible to coronavirus infections. But because they have so much close contact at school, canceling in-person classes plays a key role in flattening the curve of an outbreak.

Litvinova says she is doubtful that schools, especially in big cities, can reliably enforce social distancing to reduce the number of contacts. "It's very difficult to explain to children that they shouldn't stay with their friends or talk with them or be close to each other."

Christakis is himself an epidemiologist by training. But he says these concerns are exactly why experts from different backgrounds need to be consulted, so that the risks of reopening schools can be properly balanced with the risks of keeping them closed. "If we declared the meat supply a national emergency, we should do the same with the brain supply."

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