By Anaridis Rodriguez

WELLESLEY (CBS) – The Centers for Disease Control released new COVID-19 guidance Friday, spelling out best practices for reopening schools. CDC scientists say in-person instruction can resume safely if schools commit to key mitigation strategies — like wearing masks, distancing, hand washing, cleaning and contact tracing.

Some private schools adopted the safety measures last fall and have been offering, full-time, in-person, instruction since. St. John School in Wellesley is one of them.

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“It wasn’t [a question of] are we going to open, it was how are we going to open?” said St. John School Principal Siobhan Mahoney. “We had a COVID task force that met throughout the summer to identify best practices.”

The small parochial school, of 218 students, divided classes into cohorts to minimize movement, invested in air purifiers, plastic barriers, cleaning supplies and personal protective equipment. Mahoney says the safety upgrades cost an estimated $41,000. So far, administrators have seen fewer than five confirmed cases and no in-school transmission.

Recently, the school also set up pooled testing. The program is voluntary, and the strategy calls for multiple students to be tested together. If the sample tests positive, students in the group are tested again individually. The initiative was made possible by a $6,000 donation from Dr. Michael Misialek, associate chair of pathology at Newton Wellesley. Misialek’s oldest is a St. John student. The donation will help the school get through two rounds of testing.

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“It’s like testing ten for the price of one, pooled testing works when there’s a low prevalence of disease in the community,” said Dr. Misialek. “The science is becoming clear, as we learn more, that schools can be safe. That they aren’t a super spreader environment.”

Private and parochial schools don’t qualify for state subsidies. Last month, the Department of Elementary and Secondary Education announced it will rollout pooled testing, at no cost to districts, until March 28. Dr. Misialek says as communities get ready to welcome students back into the classroom, testing remains an effective way in controlling the spread of the virus. He’s now advocating state education officials include all schools when drafting criteria for state funding dedicated to testing. “It’s a great example of how school can be safe with effective strategies for mitigation and testing,” Dr. Misialek said.

Seventy percent of students participated in St. John’s first round of testing. Misialek is now helping Mahoney encourage all families to participate in the second round, scheduled for after the February break.

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“I’m an educator. I don’t have a medical background,” said Mahoney. “Having his [Dr. Misialek’s] background in the medical field to support us get pooled testing up and running is truly a blessing.”

Anaridis Rodriguez