The Missing Piece — SARS-CoV-2 Testing and School Reopening

“Available guidance documents typically instruct schools to gain access to testing by contacting local public health departments, and few schools appear to have solidified a strategy — especially one that extends beyond testing of symptomatic persons.

[..] Most reopening plans instead focus on screening for Covid-19 symptoms. Yet recent research indicates that symptom screening alone will not enable schools to contain Covid-19 outbreaks. Because an estimated 40% of Covid-19 cases are asymptomatic and 50% of transmissions occur from asymptomatic persons, we believe that screening testing is critical.

[..] SARS-CoV-2 testing presents at least three challenges for schools. The first is access to testing. Disparities in access persist, particularly for people without severe symptoms or known Covid-19 contacts. Whereas many universities can provide testing using their own labs, K–12 schools are reliant on either public health departments or private contracting. [..] Costs of individual tests in the community range from $50 to $200, and federal law does not require employers or insurers to pay for SARS-CoV-2 screening tests administered as part of a return-to-work or return-to-school strategy. Congressional funds for testing the uninsured are also limited to tests for “diagnostic” purposes.

A second major challenge is the lag time in receiving test results. The latest available survey data, from August 2020, indicate that only 26% of tested Americans received their results within a day; 35% waited 4 or more days. [..] Even outside the high-contact setting of schools, delays in returning results have disturbing consequences: a modeling study showed that same-day results can prevent 80% of new transmissions, whereas a 7-day delay stops only 5%.

[..] schools must ensure timely reporting of test results, which labs cannot legally disclose without authorization. Schools could counsel parents and secure their legal authorization to have their Covid-19 test results released directly to school officials or could ask parents to disclose those results to the school themselves. Alternatively, schools could build a rapid-feedback loop among testing laboratories, the public health department, and potential contacts, in accordance with public health exceptions to privacy laws. There is no indication that these steps are part of schools’ plans, however.

Third, implementing recommended responses to positive SARS-CoV-2 test results is logistically daunting. Screening testing involves a potentially large number of both true positive and false positive results, and the best practice is to isolate persons with positive results and quarantine in-school contacts until those persons test negative or the incubation period has elapsed. In schools not using cohorting, quarantines may affect a large number of students and staff. For example, a high school in Cherokee County, Georgia, had to quarantine more than a quarter of its 1800 students and suspend in-person learning after 25 students tested positive. Thus, in addition to arranging quarantines, schools must be able to deliver remote education to confined students on short notice.

Because testing-related challenges pose a serious threat to the viability of school reopening plans, we believe that increasing routine screening using rapid tests in schools should rank among our most urgent national priorities.”

Full editorial, Rafiei Y and Mello MM. New England Journal of Medicine, 2020.10.21