As schools across the country grapple with bringing kids back into the classroom, parents — and teachers — are worried about safety. We asked pediatricians, infectious disease specialists and education experts for help evaluating school district plans.

What we learned: There's no such thing as zero risk, but certain practices can lower the risk of an outbreak at school and keep kids, teachers and families safer.

If you're considering sending your child back to school this fall or in the coming months, start with assessing both your own family's personal risk and the level of spread in your community. The American Federation of Teachers says it doesn't consider in-person school to be safe unless fewer than 5% of coronavirus tests in an area are positive. As of late July, that one benchmark disqualified eight of the 10 largest public school districts in the country.

If your family is relatively healthy and local numbers look good, here's how to weigh the key elements of a school reopening plan.

1) Getting to school: Riding the bus

Look for: Limited capacity and physical distancing. Plus masks

Buses combine several risk factors for spread: Kids are in a closed space, for an extended period of time, often with poor ventilation.

"The best option for children getting to school would be for their parents to drop them off," says Dr. Tina Tan, pediatrics infectious disease specialist at Northwestern University in Chicago. Or walk or bike to school.

But that's not an option for many families, so to make busing safer, limit capacity to 50%, says Ravina Kullar, an epidemiologist and spokesperson for the Infectious Disease Society of America. The children and the driver should be physically distanced by at least 6 feet, and everyone should wear masks. Ideally there's assigned seating, and tape marks designating where kids should sit, she says.

If possible, keep the bus windows open to improve ventilation, says Dr. Judith Guzman-Cottrill, a pediatric infectious disease specialist at Oregon Health & Science University. Airflow helps dilute the virus, thus reducing the risk of infection.

"Students' hands should be sanitized before they enter the bus," says Laurie Combe, president of the National Association of School Nurses. Combe suggests mounting a sanitizer dispenser at the entrance of the bus.

2) Entry-to-school guidelines

Look for: Clear policies requiring sick kids and teachers to stay home

Our experts agree: Plans should drive home the message that staff and kids must stay home if they have any symptoms of COVID-19.

"As a society, we are going to have to learn that if we're sick, we stay home — always," says Dr. William Miller, an epidemiologist at Ohio State University. It's a big cultural shift, he says, because many of us are used to "powering through illness, and sometimes, we expect the same of our children."

There is no one perfect way to enforce this. Some experts suggest schools rely on messaging, while others prefer schools screening for symptoms.

Symptom checks at school may not be foolproof, but they reinforce the message that parents should keep kids home if they're sick, says Laurie Combe. "If there was optimal staffing for this situation, then the best practice would be to be able to screen as people enter the building."

The CDC currently does not recommend schools conduct widespread symptom screenings. It suggests parents check their children at home before coming to school.

Kids should stay home even if they have only very mild symptoms, "just a headache or stomachache," says Dr. Preeti Malani, an infectious disease specialist and chief health officer at the University of Michigan. And when parents are sick, children should stay home too, adds Miller. This may be difficult for economic reasons for many families.

If teachers or staff have to miss work, then, Malani says, school "policies have to support it, whether it's paid time off or making sure that there's not a penalty for missing work."

To encourage symptomatic kids to stay home, some school districts may need to revisit attendance policies that reward students for showing up consistently and penalize them for missing days.

Under debate: Temperature checks

Several experts argue for schools conducting daily temperature checks. A good rule of thumb is that any child with a fever exceeding 100.4 F "should be sent home or to the doctor's office for evaluation," says Dr. Dial Hewlett, an infectious disease specialist who has consulted with schools in Westchester County, N.Y.

Others, like Malani, are skeptical. She says children infected with the coronavirus may show no symptoms, including fever, so temperature screenings can miss the real cases and could be a waste of resources. And Combe questions the accuracy of infrared temperature screening devices and worries about student privacy.

3) Masking policies

Look for: Consistent, mandatory mask usage for kids and adults

All our experts agree that masks are a vital part of a school's reopening plan.

Especially "in those situations where they cannot physically distance 6 feet or more from each other," says Tan. This advice is in line with the CDC's school reopening guidelines.

Miller adds that it's critical that teachers and staff wear masks because "the distance that airborne particles are dispersed is greater for adults than children." Some studies suggest adults are more likely to infect children than the other way around.

But masks aren't optimal for everyone, including anyone with health problems that affect breathing, those interacting with people who are hard of hearing and very young children. The CDC suggests schools consider using masks with a see-through covering over the mouth for young students or students with disabilities.

For younger kids especially, schools should structure in times when students can "take off their masks and have a breather," says Hewlett. These mask breaks would preferably be outdoors, he says.

Under debate: Face shields Some educators like the idea of a clear, plastic face shield as a stand-alone face covering for younger children. They're more comfortable, make it harder to touch the face and easier to see expressions. But there's no strong evidence that face shields reduce infection rates, says Miller. And the CDC does not recommend them as a substitute for face masks.

Face shields or goggles could be used in addition to masks, especially for teachers as a way to protect their eyes. In a virtual town hall with the American Federation of Teachers, Dr. Anthony Fauci was asked what teachers should wear in class. "The minimum would be the mask, eye shield if you can have it and possibly gloves," he replied.

4) In Class: Social distancing and cohorts

Look for: 6 feet between desks, small class sizes and cohorts

Physical distancing is a cornerstone of coronavirus protection in school, just as it is in the grocery store or at a White House briefing.

Ideally, desks need to be placed at least 6 feet apart. Some schools are considering moving traditional classes into larger rooms like auditoriums, music rooms or gyms, says Hewlett. Tan advises holding classes outdoors when possible.

"There really is no one right way to do this," says Tan. Schools have to adapt their space as best they can.

One solution many experts recommend is a system of cohorts and staggered schedules. Each class forms a self-contained pod that doesn't interact with other children. The goal, says Miller, is to reduce the number of people any individual is exposed to and to "reduce the density of people in any given space."

Malani suggests bringing special-topic teachers, like art and music teachers, to the pod's classroom. This way, students don't have to rub elbows traveling through hallways.

"If the bubble stays safe, then everyone within it stays safe," Miller says.

As part of a cohort system, many schools are opting to set up a staggered schedule, in which one group of students goes on Wednesday and Friday for example, while another group goes Tuesday and Thursday, and each group alternates Mondays. Another option is to have one group of students go in the mornings and another in the afternoons.

Under debate: Plexiglass dividers

Plexiglass dividers have been used in schools in Europe and Asia. But "the data for plexiglass are limited," says Miller, explaining that unless dividers go to the ceiling, "the air currents will simply flow around them." Malani says plexiglass barriers are most useful in front offices, for greeters or security guards sitting in high-traffic areas.

5) What to do when someone gets sick

Look for: Requirement for anyone with symptoms to self-isolate — and collaboration with the local health department

Schools need to have a plan in place for what to do when kids develop symptoms. It's critical this is communicated clearly, says Hewlett, so that "everyone understands what's going to happen if a child develops infection."

Most scientists we spoke to agreed that any student or staff with symptoms should be tested or evaluated by a doctor. But few school plans we reviewed specify this as a requirement for students; instead they simply ask that anyone with concerning symptoms or a known exposure stay home. (Some districts, like Detroit, are asking all staff to get tested prior to the start of school.)

With or without test results, anyone with symptoms needs to stay home for at least 10 days after symptom onset, and schools should have a protocol for deciding whether others exposed need to quarantine. This would be best done in consultation with the local health department, says Malani, and will be based on the severity of the symptoms and how much interaction the child had with others.

If anyone does test positive, schools need to collaborate with local health departments, Hewlett says, so they can provide contact tracing and guidance for when to shut down a school if needed.

Establishing a stable pod or cohort of students could help prevent school shutdowns, says Guzman-Cottrill, because if a person in the cohort tests positive, exposure is limited to the cohort and only those students need to quarantine.

Future goal: Routine testing

Several experts said regular testing of asymptomatic students and staff is not feasible, with current testing shortages and delays. But if it were, it could help schools open safely.

"Weekly testing would be ideal, as it would identify asymptomatic infections," says Dr. Danielle Zerr, pediatric infectious disease specialist at Seattle Children's Hospital.

Once new technologies are approved and rapid tests are available, schools should do routine testing, says Dr. Michael Mina, an immunologist and epidemiologist at Harvard T.H. Chan School of Public Health. "Short of vaccines, daily cheap rapid tests performed at home or at school are a clear avenue to keep cases low and prevent outbreaks from growing," he says.

6) Sanitizing surfaces

Look for: Focus on hand hygiene and cleaning high-touch surfaces

The CDC says the major route of COVID-19 transmission is through droplets that are expelled when we cough, sneeze or talk. But the virus can live on surfaces for hours and possibly days.

But rather than worry about constantly cleaning every part of the school, says Zerr, "focus on frequent hand hygiene and wiping down frequently touched surfaces."

To promote hand hygiene, schools could have sanitizer dispensers in classrooms and hallways, says Malani, and keep bathrooms well-stocked with paper towels and soap.

Schools should focus cleaning efforts on high-touch surfaces like doorknobs, bathroom doors and sink areas multiple times a day. And some opportunities for touching surfaces could be eliminated. "Classroom doors can be left open until class starts so that each student does not need to open the door," Tan says. Cleaning desks is less of a worry, Miller says, because students don't touch one another's desks that often.

It's important to thoroughly clean bathrooms that children routinely use, says Hewlett. These are high-touch areas and can get crowded. Miller says, "Bathrooms must have strong exhaust fans," as airflow dilutes virus that may accumulate in the air.

Open for debate: Disinfectant misters may not be worth it, says school nurse Laurie Combe, because spraying disinfectant willy-nilly might create its own hazards. "I don't know that we have enough data that tells us that that is safe," she says.

7) Air circulation

Look for: As much airflow as possible

While person-to-person spread is the greater risk, scientists are also concerned about the virus accumulating in indoor air. So the guiding principle is to bring in as much fresh air as possible to dilute and disperse viral particles. "We simply want lots of air exchange with the outside," says Miller.

Joshua Santarpia, a microbiologist who studies biological aerosols at the University of Nebraska Medical Center, says that schools should assess their ventilation systems to see if they can be modified to optimize airflow in each classroom. "The more air changes, the better," he says.

Newer school buildings with modern systems typically are set up to recirculate indoor air because this saves energy, says Peter Fehl, president of building management systems for Honeywell. But by adjusting those settings, it's possible to get "seven or eight times more fresh air," says Fehl.

In addition, schools can replace their system's HEPA filters — which remove most very fine particles — more frequently, probably once a month, Fehl says.

But many schools have older systems that don't have the option of increasing fresh air.

For schools that can't afford to update their systems, Santarpia recommends free-standing HEPA filters. He says the size of the room and how much noise will be made need to be considered when choosing a device, but if used correctly, these filters "could dramatically reduce airborne contaminants."

Unfortunately, the quality of air in classrooms may come down to resources. Wealthier districts will likely have more modern facilities and systems.

Open to debate: UV light systems

There are newer technologies such UV light systems that are garnering attention as well, but "the jury is still out on more novel interventions, like UV light and ionizers," Santarpia says. One challenge: When air is moving through a duct system, it can be difficult to get the kind of UV intensity and exposure time necessary to kill viruses.

8) Lunch and snacks

Look for: Staggered cafeteria times or in-classroom dining

Eating lunch and snacks requires removing face masks, so social distancing is the key here.

Schools should avoid having kids eat in a crowded cafeteria. "This may mean eating in classrooms," says Zerr, adding that kids should stick with their designated pod and "remove masks only to eat."

Other experts suggest staggering lunchtimes to reduce the number of students who are in the cafeteria so they can socially distance and keep students in their social bubbles, whether they are eating in their classrooms or the cafeteria.

"Purchasing lunches should be OK if students are spaced out and classes do not intermingle," Miller says. Many schools are planning to serve a bag lunch which students can carry back to their classroom, although there are concerns these lunches may not be as nutritious.

9) Recess

Look for: Outdoor recess in small supervised groups

Kids need to run, play and take breaks, says Kullar. And "we know outdoor time is less risky than indoor time," she says. Most of our experts agree — recess should take place outside, ideally with enough room for kids to socially distance, so they can remove their masks.

If kids can't stay 6 feet apart while at recess, our experts agreed they should not remove their masks, especially if inside.

Kullar advises staggering recess times, sending kids out in "small, supervised groups." And everyone should immediately wash hands when reentering the building, she adds.

Some of our experts recommended not just a single recess, but multiple "mask breaks" during the day. This could increase chances that kids comply with mask use the rest of the time, says Miller.

10) Gym and sports

Look for: Outdoor activities and no contact sports

Games should be outside and spaced as much as possible, says Miller, adding that kickball is "relatively safe." Modified forms of no-contact tag, hide-and-go-seek or anything where kids are running around and generally staying away from one another also work, he says. "If you can't go outside, use the gym or the cafeteria as a larger play space," Miller says.

Avoid sports that involve physical contact, cautioned several of our experts. "Contact sports should be suspended until we see a decrease in cases," says Kullar. This means no team sports like basketball, football, baseball, wrestling and cheerleading, Tan added.

Cross-country running and tennis are safer bets than other sports, says Malani. "With tennis, there's enough distance, particularly with singles play, that other than making sure that you keep your hands clean, there's not a lot of additional precautions that would be needed." Malani says.

Masks can come off if students are breathing hard, as long as they are well-distanced, Zerr says.

11) The missing ingredient

Look for: A boost in funding

We also asked our experts for other ideas that should be the components of any good back-to-school plan.

The No. 1 answer? Money.

Lily Eskelsen García, president of the National Education Association, says of the things schools need to keep students safe and healthy — from face masks to hand sanitizer — "everything costs money." While recently lobbying for school funding, she recalls one politician complained, "Money, money money, all you guys want is money." What schools really needed, the politician said, was plexiglass dividers. And Eskelsen García said, "Oh, I had no idea they were giving those away! Put me down for 52 million!"

The Council of Chief State School Officers has estimated that schools need as much as $245 billion to reopen safely and to plug holes in state budgets caused by the pandemic-induced recession. The White House has recommended allocating $105 billion in current negotiations but wants to tie much of that money to schools physically reopening.

And of course, some schools have more resources to start with. The bottom line is wealthier school districts will have an easier time implementing some of these safety measures. Without an influx of funding "inequities that exist now will likely be increased," Malani says.

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