Daily testing for contacts of individuals with SARS-CoV-2 infection and attendance and SARS-CoV-2 transmission in English secondary schools and colleges: an open-label, cluster-randomised trial

Abstract

Background School-based COVID-19 contacts in England have been asked to self-isolate at home, missing key educational opportunities. We trialled daily testing of contacts as an alternative to assess whether this resulted in similar control of transmission, while allowing more school attendance. Methods We did an open-label, cluster-randomised, controlled trial in secondary schools and further education colleges in England. Schools were randomly assigned (1:1) to self-isolation of school-based COVID-19 contacts for 10 days (control) or to voluntary daily lateral flow device (LFD) testing for 7 days with LFD-negative contacts remaining at school (intervention). Randomisation was stratified according to school type and size, presence of a sixth form, presence of residential students, and proportion of students eligible for free school meals. Group assignment was not masked during procedures or analysis. Coprimary outcomes in all students and staff were COVID-19-related school absence and symptomatic PCR-confirmed COVID-19, adjusted for community case rates, to estimate within-school transmission (non-inferiority margin <50% relative increase). Analyses were done on an intention-to-treat basis using quasi-Poisson regression, also estimating complier average causal effects (CACE). This trial is registered with the ISRCTN registry, ISRCTN18100261. Findings Between March 18 and May 4, 2021, 204 schools were taken through the consent process, during which three decided not to participate further. 201 schools were randomly assigned (control group n=99, intervention group n=102) in the 10-week study (April 19–May 10, 2021), which continued until the pre-appointed stop date (June 27, 2021). 76 control group schools and 86 intervention group schools actively participated; additional national data allowed most non-participating schools to be included in analysis of coprimary outcomes. 2432 (42·4%) of 5763 intervention group contacts participated in daily contact testing. There were 657 symptomatic PCR-confirmed infections during 7 782 537 days-at-risk (59·1 per 100 000 per week) in the control group and 740 during 8 379 749 days-at-risk (61·8 per 100 000 per week) in the intervention group (intention-to-treat adjusted incidence rate ratio [aIRR] 0·96 [95% CI 0·75–1·22]; p=0·72; CACE aIRR 0·86 [0·55–1·34]). Among students and staff, there were 59 422 (1·62%) COVID-19-related absences during 3 659 017 person-school-days in the control group and 51 541 (1·34%) during 3 845 208 person-school-days in the intervention group (intention-to-treat aIRR 0·80 [95% CI 0·54–1·19]; p=0·27; CACE aIRR 0·61 [0·30–1·23]). Interpretation Daily contact testing of school-based contacts was non-inferior to self-isolation for control of COVID-19 transmission, with similar rates of symptomatic infections among students and staff with both approaches. Infection rates in school-based contacts were low, with very few school contacts testing positive....

Daily antigen testing to reduce disruption when schools return

“…Young and colleagues 5 found similar numbers of secondary cases identified in the intervention and control schools, with 44 (1•5%) of 2981 asymptomatic contacts in the intervention group and 14 (1•6%) of 886 asymptomatic contacts in the control group testing positive for SARS-CoV-2 (adjusted odds ratio 0•73 [95% CI 0•33-1•61]; p=0•44). Overall, school attendance was not significantly greater in the daily testing group than in the control group.…”

“…The trial involved 201 schools and was undertaken at a time of moderate community prevalence (7-day incidence 30-180 per 100 000 population across the study) 6 and during the emergence of the SARS-CoV-2 delta (B.1.617.2) variant in England from April 19 to June 27, 2021. 5 Young and colleagues 5 compared the impact of daily antigen lateral flow testing for 7 days with standard 10-day home isolation on school attendance and SARS-CoV-2 transmission among staff and an ethnically diverse group of 11-18-year-old students (about 25% of whom were non-White) who were close contacts of a proven case.…”

Feasibility and acceptability of daily testing at school as an alternative to self-isolation following close contact with a confirmed case of COVID-19: A qualitative analysis

“…Improved communications between schools and parents may reduce the uncertainty to some degree. Furthermore, evidence suggests that rates of COVID-19 in school-based contacts are very low [6]. Communication of such findings may alleviate concerns about having to isolate following positive test results.…”

“…Data from a randomised trial of daily contact testing (DCT) in schools carried out during a period of high infection rates in the UK suggests that DCT was not inferior to self-isolation for controlling transmission of SARS-CoV-2 within schools [6]. However, if this approach is to be implemented widely, it is critical that we understand the perspective of those who will be delivering and receiving DCT.…”

Comprehensive Survey of IoT, Machine Learning, and Blockchain for Health Care Applications: A Topical Assessment for Pandemic Preparedness, Challenges, and Solutions

“…In situations where training data technically removes parts of the population data, the relevance of the model to larger populations could be discredited. The inconsistent and incomplete labeling of ethnic, demographic, and other racial information may also affect data quality [247][248][249]. Machine learning algorithms may unexpectedly increase inconsistency by exaggerating the trial of pandemics and improperly notifying resource allocation based upon insufficient or incomplete data instances.…”