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SARS-CoV-2 Test-to-Stay in Daycare
Felix Dewald1,2,3, Gertrud Steger1, Irina Fish1
1Institute of Virology, Faculty of Medicine and University Hospital Cologne.
Insights
The test-to-stay approach in daycare, involving serial testing instead of quarantine after SARS-CoV-2 exposure, was found to be safe. This strategy significantly reduced quarantine days for children without increasing infection rates.
Area of Science:
- Pediatric infectious disease epidemiology
- Public health policy in childcare settings
- Diagnostic testing strategies
Background:
- Test-to-stay (TTS) strategies involve serial testing of children exposed to SARS-CoV-2 in daycare, circumventing traditional quarantine measures.
- Assessing the safety and efficacy of TTS is crucial for maintaining childcare operations during respiratory pathogen outbreaks.
Purpose of the Study:
- To evaluate the safety of implementing a test-to-stay screening approach in daycare facilities.
- To determine if the TTS strategy impacts infection rates among young children compared to quarantine.
Main Methods:
- A large-scale study involving 714 daycare facilities and approximately 50,000 children (≤6 years) in Cologne, Germany, from March 2021 to April 2022.
- Utilized SARS-CoV-2 Pool-polymerase chain reaction (PCR) screening, transitioning from quarantine to a TTS approach during the study period.
- Employed regression discontinuity in time (RDiT) analyses, linking PCR test data with reported infections to assess changes in infection frequency.
Main Results:
- Over 219,000 Pool-PCRs and 352,000 Single-PCRs were conducted, with 2.93% of Pool-PCRs testing positive and 17,208 infections reported.
- The TTS concept is estimated to have reduced quarantine duration by 7 to 20 days per eligible child over 30 weeks.
- RDiT analysis indicated a 26% reduction in infection frequency among children, with no significant increase attributable to the TTS approach, robust across various adjustments.
Conclusions:
- The study provides evidence supporting the safety of the test-to-stay approach as an alternative to quarantine in daycare settings.
- The test-to-stay strategy presents a viable option for minimizing quarantine requirements following exposure to respiratory pathogens in childcare environments.
Background And Objectives:
Test-to-stay concepts apply serial testing of children in daycare after exposure to SARS-CoV-2 without use of quarantine. This study aims to assess the safety of a test-to-stay screening in daycare facilities.
Methods:
714 daycare facilities and approximately 50 000 children ≤6 years in Cologne, Germany participated in a SARS-CoV-2 Pool-polymerase chain reaction (PCR) screening from March 2021 to April 2022. The screening initially comprised post-exposure quarantine and was adapted to a test-to-stay approach during its course. To assess safety of the test-to-stay approach, we explored potential changes in frequencies of infections among children after the adaptation to the test-to-stay approach by applying regression discontinuity in time (RDiT) analyses. To this end, PCR-test data were linked with routinely collected data on reported infections in children and analyzed using ordinary least squares regressions.
Results:
219 885 Pool-PCRs and 352 305 Single-PCRs were performed. 6440 (2.93%) Pool-PCRs tested positive, and 17 208 infections in children were reported. We estimated that during a period of 30 weeks, the test-to-stay concept avoided between 7 and 20 days of quarantine per eligible daycare child. RDiT revealed a 26% reduction (Exp. Coef: 0.74, confidence interval 0.52-1.06) in infection frequency among children and indicated no significant increase attributable to the test-to-stay approach. This result was not sensitive to adjustments for 7-day incidence, season, SARS-CoV-2 variant, and socioeconomic status.
Conclusions:
Our analyses provide evidence that suggest safety of the test-to-stay approach compared with quarantine measures. This approach offers a promising option to avoid use of quarantine after exposure to respiratory pathogens in daycare settings.
