The coronavirus is spreading through schools once again. But classrooms probably aren’t the main culprit — experts say locker rooms and fields are more to blame.

North Carolina has seen a “sharp increase” in clusters of covid-19 in middle and high school sports teams, the state’s department of health and human services announced Wednesday.

Between July and September, 45 percent of all clusters in North Carolina middle and high schools stemmed from sports teams, according to the department, with a spike in August at the beginning of the school year.

Experts have been studying the risks of youth sports since students returned to their courts and fields last year. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, pointed to youth sports as a high-risk activity for coronavirus spread in April.

“We’re finding out that it’s the team sports where kids are getting together, obviously many without masks, that are driving it, rather than in the classroom spread,” Fauci said on “Good Morning America.” “When you go back and take a look and try and track where these clusters of cases are coming from in the school, it’s just that.”

Outbreaks associated with sports have been tracked across the nation, from hockey practices in Minnesota to football games in Florida. Experts say sports-related clusters were common last year, so it’s no surprise they’re back — especially amid the spread of the highly transmissible delta variant and pandemic fatigue.

And though children generally experience less-severe symptoms of covid-19, the delta variant has driven up pediatric hospitalizations. Some experts have said this part of the pandemic could be the most dangerous time for children so far.

North Carolina reported that last week, children 17 and under comprised more than 30 percent of the state’s new covid-19 cases — the highest percentage of the pandemic.

“We need everyone, including our student-athletes and their coaches, to increase layers of prevention to fight this more contagious Delta variant: Don’t wait to vaccinate and urge others to do the same,” North Carolina State Health Director Elizabeth Cuervo Tilson said in a statement.

North Carolina public, charter and private middle and high schools reported 42 athletics-related clusters from July 1 to Sept. 2, with all but four occurring in August.

Kristin Moffitt, an infectious diseases physician at Boston Children’s Hospital, said coronavirus spread among sports teams is not new.

“This is not something unique to the delta strain,” she said. “This is something that is inherent in the contact involved with school sports, and not just contact on the field or in the context of workouts, but I think some of the gatherings of athletes off the field as well.”

According to the American Academy of Pediatrics, most of the coronavirus spread linked to outdoor sports can be traced to off-field activities, including eating meals in groups or traveling without masks.

Moffitt said while vaccination is the most effective way to guard against the coronavirus, parents should also consider the context of the sport their child plays and other precautions they could take — especially parents of children who are too young to get the shot.

Experts and coaches are urging student-athletes to wear masks whenever possible, avoid sharing water bottles and maintain as much distance as they can.

Arguments that mask mandates violate an individual’s constitutional right to liberty might not cut it with the Supreme Court. Here's why. (Drea Cornejo/The Washington Post)

In southern states where transmission is especially high, sports would ideally be postponed, said Allison Ross Eckard, division chief of pediatric infectious diseases at the Medical University of South Carolina.

The Centers for Disease Control and Prevention advises that high-risk sports and extracurriculars be canceled in places where there are high rates of community transmission — unless everyone involved is fully vaccinated. High-risk activities are ones that involve increased exhalation, especially indoors, the CDC said. Football and wrestling are considered high risk, while golf and diving are considered low.

Eckard, who is also medical director of the Back2Business program for South Carolina schools, said if the priority is to keep children in school, districts need to get sport-related transmission under control so it stops affecting classrooms.

For teams that do continue playing, Eckard said it’s often important for coaches to set an example of how to minimize risk. She also said while she’s received significant pushback from parents about quarantining asymptomatic student-athletes, isolating infected people is still key to managing coronavirus spread.

“There is a widespread misconception that younger kids cannot get covid, cannot pass it and cannot get severely ill from it,” Eckard said. “And that is all not true, particularly with delta, we are seeing just as high rates of younger children acquiring covid and transmitting it, not only to their teammates and their classmates, but to their family members as well.”

Schools should also consider routine coronavirus testing or screening for athletes, coaches and volunteers who are not fully vaccinated, the CDC said.

And while close-contact and indoor sports pose a heightened risk of transmission, the CDC says activities such as band, choir and others that meet indoors could present similar risks.

Rochelle Walensky, director of the Centers for Disease Control and Prevention, said on March 19 that students can now sit three feet apart while masked. (The Washington Post)

The American Academy of Pediatrics strongly recommends face masks be worn during indoor sports, unless their use presents additional risk such as in swimming, cheerleading, wrestling and gymnastics.

Experts stressed that while sports can have physical and mental health benefits, the heightened risk of coronavirus transmission needs to be taken seriously.

“I think everyone is relieved to see that the priority this year is to keep kids in schools, first and foremost,” Moffitt said. “ And then beyond that, to keep their extracurricular activities and sports up and running — but realizing it needs to be done safely.”

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