At-home self-testing of teachers with a SARS-CoV-2 rapid antigen test to reduce potential transmissions in schools

Abstract

BackgroundRapid antigen tests for SARS-CoV-2 became available recently, offering an opportunity to vastly increase testing capacities. Antigen tests offer lower sensitivity than the gold standard, RT-PCR, but rapid sample-to-answer time. High-frequency testing with an antigen test may offset the lower sensitivity, and testing can be done with at-home collection of samples, offering potential benefit in screening efforts. In this study, we set out to evaluate the practical application of self-performed high-frequency antigen test in a school setting.MethodA total of 711 teachers from 86 schools were enrolled in a seven-week study. After instruction, participants tested themselves every 48 hours at home with a rapid antigen test for SARS-CoV-2 (target: nucleocapsid protein) in a self-collected anterior nasal swab. Positive results in the antigen test were confirmed via RT-PCR from the same sample that had been determined to be positive by the study participant. A questionnaire was given to all participants to evaluate whether the test failed to detect infection.Findings10 836 tests from 602 teachers were recorded and analyzed. A total of five confirmed cases of viral shedding of SARS-CoV-2 was detected by use of the antigen test. One study participant with a SARS-CoV-2 infection was presymptomatic and four were mildly symptomatic at the time of the antigen test. Sixteen false positive antigen tests (0.15% of all tests) were reported, predominantly when the local incidence in the general population was low. In four cases, the study participant reported that a PCR had detected a SARS-CoV-2 infection, but the antigen test was negative, indicating a false negative result.InterpretationHigh-frequency, self-performed rapid antigen tests can detect individuals with a SARS-CoV-2 infection, and therefore potentially reduce transmissions. Testing may be most beneficial when applied during high local incidence of SARS-CoV-2 infections and when mild or atypical symptoms are present. To avoid a high rate of false positive results, a test with optimized specificity should be used.FundingThe study was commissioned and funded by the Hessian Ministry of Education and the Hessian Ministry of Integration and Social Affairs.

Empirical evidence to understand the human factor for effective rapid testing against SARS-CoV-2

“…While previous work has shown a “substantial concordance” between participant- and clinician-administered tests and interpreted results ( 14 ) (preprints without peer review: refs. 15 and 16 ), it is unclear whether test users trust the results of a test and whether this affects their behavior after receiving them. Moreover, allowing self-determined testing for everyone could elicit risky behavior and complacency ( 11 , 13 ) (risk compensation).…”

Multicenter Evaluation of a Fully Automated High-Throughput SARS-CoV-2 Antigen Immunoassay

“…They are unsuitable for automation and additional human operators are required at the same proportion as testing capacity is scaled up. While there are clear benefits of a point-of-care test that can be carried out with minimal training and requiring no specialized equipment [ 17 ], testing en masse (e.g., in healthcare facilities) is vastly more efficient when performed automatically using high-throughput immunoassay platforms.…”

Multicenter evaluation of a fully automated high-throughput SARS-CoV-2 antigen immunoassay

“…They are largely unsuitable for automation and additional human operators are required at the same proportion as testing capacity is scaled up. While there are clear benefits of a point-of-care test that can be carried out with minimal training and requiring no specialized equipment (16), testing en masse (e.g. in healthcare facilities) is vastly more efficient when performed automatically using high-throughput immunoassay platforms.…”