Modifications to student quarantine policies in K-12 schools implementing multiple COVID-19 prevention strategies restores in-person education without increasing SARS-CoV-2 transmission risk, January-March 2021.

OBJECTIVE: To determine whether modified K-12 student quarantine policies that allow some students to continue in-person education during their quarantine period increase schoolwide SARS-CoV-2 transmission risk following the increase in cases in winter 2020-2021. METHODS: We conducted a prospective cohort study of COVID-19 cases and close contacts among students and staff (n = 65,621) in 103 Missouri public schools. Participants were offered free, saliva-based RT-PCR testing. The projected number of school-based transmission events among untested close contacts was extrapolated from the percentage of events detected among tested asymptomatic close contacts and summed with the number of detected events for a projected total. An adjusted Cox regression model compared hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy. RESULTS: From January-March 2021, a projected 23 (1%) school-based transmission events occurred among 1,636 school close contacts. There was no difference in the adjusted hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy (hazard ratio = 1.00; 95% confidence interval: 0.97-1.03). DISCUSSION: School-based SARS-CoV-2 transmission was rare in 103 K-12 schools implementing multiple COVID-19 prevention strategies. Modified student quarantine policies were not associated with increased school incidence of COVID-19. Modifications to student quarantine policies may be a useful strategy for K-12 schools to safely reduce disruptions to in-person education during times of increased COVID-19 community incidence.

An Examination of SARS-CoV-2 Transmission Based on Classroom Distancing in Schools With Other Preventive Measures in Place-Missouri, January-March 2021.

OBJECTIVES: Classroom layout plays a central role in maintaining physical distancing as part of a multicomponent prevention strategy for safe in-person learning during the COVID-19 pandemic. We conducted a school investigation to assess layouts and physical distancing in classroom settings with and without in-school SARS-CoV-2 transmission. METHODS: We assessed, measured, and mapped 90 K-12 (kindergarten through grade 12) classrooms in 3 Missouri public school districts during January-March 2021, prior to widespread prevalence of the Delta variant; distances between students, teachers, and people with COVID-19 and their contacts were analyzed. We used whole-genome sequencing to further evaluate potential transmission events. RESULTS: The investigation evaluated the classrooms of 34 students and staff members who were potentially infectious with COVID-19 in a classroom. Of 42 close contacts (15 tested) who sat within 3 ft of possibly infectious people, 1 (2%) probable transmission event occurred (from a symptomatic student with a longer exposure period [5 days]); of 122 contacts (23 tested) who sat more than 3 ft away from possibly infectious people with shorter exposure periods, no transmission events occurred. CONCLUSIONS: Reduced student physical distancing is one component of mitigation strategies that can allow for increased classroom capacity and support in-person learning. In the pre-Delta variant period, limited physical distancing (<6 ft) among students in K-12 schools was not associated with increased SARS-CoV-2 transmission.

Evolution of Ventricular Assist Device Support Strategy in Children With Univentricular Physiology.

BACKGROUND: Since 2012, we have supported 18 children with single ventricle (SV) physiology on ventricular assist devices (VADs) as a bridge to decision, transplantation, or recovery. We provide a detailed report of our cumulative surgical experience and lessons learned from these patients. METHODS: We reviewed all SV-VADs between March 2012 and April 2020. Implanted SV-VADs intended for short-term support were excluded. Demographic and clinical data included palliation stage at the time of VAD implantation, cannulation configuration, device type, duration of support, circuit and device interventions, postoperative support, anticoagulation strategy, complications, mortality, and 1-year survival postdischarge. RESULTS: Five SV newborns without prior surgical palliation, 8 infants post-Norwood/hybrid procedure, 4 infants post-Glenn, and 1 infant post-Fontan were initially supported with either continuous-flow (n = 13 of 18, 72%) or pulsatile-flow (n = 5 of 18, 28%) devices. Three (17%) of 18 transitioned to another device during support. Before VAD conversion, 9 (50%) of 18 were supported by extracorporeal membrane oxygenation. Outcomes included 7 (39%) of 18 who transplanted, 2 (11%) of 18 who recovered, and 9 (50%) of 18 who died before discharge. Of these deaths, 2 occurred after transplantation and 2 after explantation, and 5 had redirection of care while on support secondary to previously undiagnosed pulmonary venoocclusive disease (n = 2) or severe neurologic events (n = 3). Overall, 6 (33%) of 18 experienced neurologic injury. At last follow-up, 9 (50%) of 18 children were alive (median 1.2 [interquartile range, 0.8-4.3] years postexplantation/transplantation). CONCLUSIONS: Our experience shows that SV children, including newborns, can be successfully bridged to desired endpoints with proper patient selection and using specific cannulation strategies. Continuing utilization of this strategy is warranted for future children requiring VAD support.