School closures and safe reopening
Do school closures and school reopenings affect community transmission of COVID-19? A systematic review of observational studies
We identified 7474 articles, of which 40 were included, with data from 150 countries. Of these, 32 studies assessed school closures and 11 examined reopenings. There was substantial heterogeneity between school closure studies, with half of the studies at lower risk of bias reporting reduced community transmission by up to 60% and half reporting null findings. The majority (n=3 out of 4) of school reopening studies at lower risk of bias reported no associated increases in transmission. School closure studies were at risk of confounding and collinearity from other non-pharmacological interventions implemented around the same time as school closures, and the effectiveness of closures remains uncertain. School reopenings, in areas of low transmission and with appropriate mitigation measures, were generally not accompanied by increasing community transmission.
Rapid, Large-Scale Wastewater Surveillance and Automated Reporting System Enable Early Detection of Nearly 85% of COVID-19 Cases on a University Campus
In this study, we employed a large-scale GIS (geographic information systems)-enabled building-level wastewater monitoring system associated with the on-campus residences of 7,614 individuals. Sixty-eight automated wastewater samplers were deployed to monitor 239 campus buildings with a focus on residential buildings. Sample processing was streamlined significantly through automation, reducing the turnaround time by 20-fold and exceeding the scale of similar surveillance programs by 10- to 100-fold, thereby overcoming one of the biggest bottlenecks in wastewater surveillance. This system, integrated with the rest of the “Return to Learn” program at the University of California (UC) San Diego-led to the early diagnosis of nearly 85% of all COVID-19 cases on campus. COVID-19 testing rates increased by 1.9 to 13× following wastewater notifications. Our study shows the potential for a robust, efficient wastewater surveillance system to greatly reduce infection risk as college campuses and other high-risk environments reopen.
Estimating data-driven COVID-19 mitigation strategies for safe university reopening
[Preprint.] We collected survey data on social contact patterns and developed an agent-based model to simulate the spread of COVID-19 in university settings. With relaxed non-pharmaceutical interventions, we estimated that immunity in at least 60% of the university population is needed for safe university reopening. Still, attention needs to be paid to extreme events that could lead to huge infection size spikes. At an immune level of 60%, continuing non-pharmaceutical interventions, such as wearing masks, could lead to an 89% reduction in the maximum cumulative infection, which reflects the possible non-negligible infection size from extreme events.
Diagnostic accuracy of rapid point-of-care tests for diagnosis of current SARS-CoV-2 infections in children: A systematic review and meta-analysis
[Preprint.] We included 17 studies with a total of 6355 pediatric study participants. All included studies compared antigen tests against RT-PCR. Only one study was at low risk of bias. The pooled overall diagnostic sensitivity and specificity in pediatric populations was 64.2% (95% CI: 57.4%-70.5%) and 99.1% (95% CI: 98.2%-99.5%), respectively. In symptomatic children, the pooled diagnostic sensitivity was 71.8% (95% CI: 63.6%-78.8%) and the pooled diagnostic specificity was 98.7% (95% CI: 96.6%-99.5%). The pooled diagnostic sensitivity in asymptomatic children was 56.2% (95% CI: 47.6%-64.4%) and the pooled diagnostic specificity was 98.6% (95% CI: 97.3%-99.3%). Performance of current antigen tests under real-life conditions varies broadly. Results should be interpreted with caution since risk of bias was predominantly judged as unclear due to poor reporting.
Evaluation of Strategies to Fight COVID-19: The French Paradigm
We collected COVID-19 mortality data and the age distribution of the deceased in France and other European countries, as well as specifically in the cities of Paris and Marseille. France is one of the European countries most impacted by COVID-19. Its proportion of deaths in people under 60 years of age is higher (6.5%) than that of Italy (4.6%) or Spain (4.7%). Excess mortality (5% more deaths) was also observed. Ile-de-France and the Grand-Est are the two French regions with the highest mortality. The proportion of deaths in the under-60 age group was considerable in Ile-de-France (9.9% vs. 4.5% in the Southern region). There are significantly higher numbers of patients hospitalized, in intensive care and deceased in Paris than in Marseille. No patient management, i.e., from screening to diagnosis, including biological assessment and clinical examination, likely explains the high mortality associated with COVID-19.