How many COVID cases trigger a closure investigation for NYC schools?

Students at M.S. 51 in Park Slope, Brooklyn walk into the building, socially distanced and masked. The foreground is steps and a green railing.
The health department will investigate whether COVID is spreading in a school only if the rate of positive cases in a school setting surpasses the rate of transmission happening across the city. (Amy Zimmer / Chalkbeat)

The New York City education department is implementing a new policy for what will trigger an investigation into possibly closing a school or classroom. 

As of Jan. 10, investigations will only happen if the rate of positive cases in a school setting surpasses the rate of transmission happening across the city — which currently stands at more than 20%. The threshold for launching an investigation will be adjusted every two weeks, according to an email sent Tuesday to principals, which outlined the new policy. 

For now, that means that an investigation will be launched only if there are 10 or more cases in a single classroom or on a sports team, because that “represents a higher-than-expected number of cases per classroom based on current positivity rates in school-aged children,” the city’s note to principals states. The threshold applies to kindergarten through 12th grade. 

The threshold for younger students – those under age 5 who aren’t yet eligible for COVID vaccines – will stay steady no matter the transmission rates in the city. An investigation is triggered if there are at least five cases in prekindergarten programs for 3- and 4-year olds, and in LYFE programs, which provide child care to public school students who are also parents. 

An education department spokesperson said schools or classrooms will close “if there is evidence of ongoing, in-school transmission,” but officials have declined to provide more specifics about how that determination is made. 

If it is determined that COVID is spreading within a school, the department of health will work with the local schools superintendent “to ensure the impacted school has all the tools they need to mitigate future instances of transmission.” That could mean ensuring current mitigation measures are being followed, providing high-quality masks, or adding more air purifiers to a school space, according to education department officials. 

City and school leaders in New York City, the nation’s largest school district, have recently implemented a raft of new policies designed to keep more children in school, reflect evolving federal health guidance, and respond to the omicron variant, which has pushed case rates to record levels.  

Among the most dramatic changes has been a shift in quarantine policies. As of January, students and staff who are exposed to someone who tested positive for COVID can now remain in school, so long as they don’t have symptoms and test negative on at-home tests that are provided by the education department. The approach is often described as “test-to-stay,” while city officials have dubbed it the “stay safe, stay open” plan. The city also recently increased the percentage of students tested for COVID in school – though the numbers remain small. 

However, many families and school staff have been wary of being in classrooms while cases surge. On Monday alone, almost 12,000 students and more than 2,200 educators reported testing positive for COVID. And attendance has remained low, dipping to 76% on Monday compared with typical average rates around 90%.

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