SARS-CoV-2 Genomic Surveillance Reveals Little Spread From a Large University Campus to the Surrounding Community

Background Coronavirus disease 2019 (COVID-19) has had high incidence rates at institutions of higher education (IHE) in the United States, but the transmission dynamics in these settings are poorly understood. It remains unclear to what extent IHE-associated outbreaks have contributed to transmission in nearby communities. Methods We implemented high-density prospective genomic surveillance to investigate these dynamics at the University of Michigan and the surrounding community during the Fall 2020 semester (August 16–November 24). We sequenced complete severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes from 1659 individuals, including 468 students, representing 20% of cases in students and 25% of total cases in Washtenaw County over the study interval. Results Phylogenetic analysis identified >200 introductions into the student population, most of which were not related to other student cases. There were 2 prolonged student transmission clusters, of 115 and 73 individuals, that spanned multiple on-campus residences. Remarkably, <5% of nonstudent genomes were descended from student clusters, and viral descendants of student cases were rare during a subsequent wave of infections in the community. Conclusions The largest outbreaks among students at the University of Michigan did not significantly contribute to the rise in community cases in Fall 2020. These results provide valuable insights into SARS-CoV-2 transmission dynamics at the regional level.

377. SARS-CoV-2 Genomic Surveillance Reveals Little Spread Between a Large University Campus and the Surrounding Community

Background Understanding SARS-CoV-2 transmission dynamics is critical for controlling and preventing outbreaks. The genomic epidemiology of SARS-CoV-2 on college campuses has not been comprehensively studied, and the extent to which campus-associated outbreaks lead to transmission in nearby communities is unclear. We used high-density genomic surveillance to track SARS-CoV-2 transmission across the University of Michigan-Ann Arbor campus and Washtenaw County during the Fall 2020 semester. Methods We retrieved all available residual diagnostic specimens from the Michigan Medicine Clinical Microbiology Laboratory and University Health Service that were positive for SARS-CoV-2 from August 16th – November 25th, 2020 (n = 2245). We extracted viral RNA, amplified the SARS-CoV-2 genome by multiplex RT-PCR, and sequenced these amplicons on an Illumina MiSeq. We applied maximum likelihood phylogenetic analysis to whole genome sequences to define and characterize transmission lineages. Results We assembled complete viral genomes from 1659 individual infections, representing roughly 25% of confirmed cases in Washtenaw County across the fall semester. Of these cases, 468 were University of Michigan students. Phylogenetic analysis revealed 203 genetically distinct introductions of SARS-CoV-2 into the student population, most of which were singletons (n = 171) or small clusters of 2 – 8 students. We identified two large SARS-CoV-2 transmission lineages (115 and 73 students, respectively), including individuals from multiple on-campus residences. Viral descendants of these student outbreaks were rare, constituting less than 4% of cases in the community. Conclusion We identified many SARS-CoV-2 transmission introductions into the University of Michigan campus in Fall 2020. While there was widespread transmission among students, there is little evidence that these outbreaks significantly contributed to the rise in COVID-19 cases that Washtenaw County experienced in November 2020. Disclosures Adam Lauring, MD, PhD, Roche (Advisor or Review Panel member) Sanofi (Consultant)

Assessing Safety Performance on Urban and Suburban Roadways of Lower Functional Classification: A Comparison of Minor Arterial and Collector Roadway Segments

Previous research of urban roadway safety performance has generally focused on roadways of high functional classifications, such as principal arterials. However,roadways with lower functional classifications, including minor arterials and collectors, typically possess characteristics that differ from those of higher roadway classes. Therefore, assumptions made on the general effect of the predictor variables from typical safety performance functions may not apply to lower roadway classes. Toaddress these knowledge gaps, a safety performance evaluation of urban/suburban minor arterial and collector roadway segments was performed using traffic androadway data along with eight years of crash data from 189 miles of two-lane urban and suburban roadways in Washtenaw County, Michigan. Mixed-effect negativebinomial models with segment-specific random intercept were developed for minor arterial and collector road segments, considering total, fatal+injury, and propertydamage only crashes. In general, minor arterial roadways showed greater crash occurrence compared to collector roads. Posted speed limit had a significant positiveassociation with crash frequency, and this effect increased when the speed limit exceeded 40 mph. The effect of speed limit was stronger on minor arterial segmentsand for fatal+injury crashes. Additionally, driveway density was found to have a significant effect on safety performance, which was stronger for commercial/industrialdriveways compared to residential driveways and for collector roads compared to minor arterials, particularly when considering residential driveways. On-street parkingwas associated with lower crash occurrence, with a stronger effect on collector roadways, likely due to greater parking turnover when compared to minor arterials.

Learning From Youth: Using Positive Outcomes to Evaluate Summer Youth Employment Programs

Summer Youth Employment Programs (SYEPs) help connect youth to opportunities for career exploration, skill development, and mentorship. Despite heightened investment in SYEPs, research regarding positive impacts is limited. Most of the common SYEP evaluation strategies are rooted in deficit thinking and focus on outcomes such as reducing violent crime, risk behaviors, gaps in unemployment, and increasing educational attainment. Despite recent shifts toward approaches that acknowledge structural oppression in adolescent research more broadly, evaluations of SYEPs often perpetuate a discourse of deficiency about marginalized communities by emphasizing disparities without acknowledging the systemic forces that create them. In this article, we utilize the Five Cs of Positive Youth Development to present an alternative set of outcomes identified from focus groups and surveys with youth ages 16 to 24 who participated in SummerWorks, a 10-week SYEP located in Washtenaw County, Michigan. Specifically, we find that SYEPs may help youth make the transition to adulthood, build community and increase their social capital, and access knowledge, resources, and opportunities. Through this approach, we hope to expand the literature on the impacts of SYEPs and encourage antiracist evaluation strategies that build on these findings and challenge deficit thinking.

SARS-CoV-2 Genomic Surveillance Reveals Little Spread Between a Large University Campus and the Surrounding Community

COVID-19 has had high incidence at institutions of higher education (IHE) in the United States, but the transmission dynamics in these settings are not well understood. It remains unclear to what extent IHE-associated outbreaks have contributed to transmission in nearby communities. We implemented high-density prospective genomic surveillance to investigate these dynamics at the University of Michigan-Ann Arbor and the surrounding community during the Fall 2020 semester (August 16th through November 24th). We sequenced complete SARS-CoV-2 genomes from 1659 individuals, including 468 students, representing 20% of cases in students and 25% of total confirmed cases in Washtenaw County over the study interval. Phylogenetic analysis identified over 200 introductions into the student population, most of which were not related to other student cases. There were two prolonged transmission clusters among students that spanned across multiple on-campus residences. However, there were very few genetic descendants of student clusters among non-students during a subsequent November wave of infections in the community. We conclude that outbreaks at the University of Michigan did not significantly contribute to the rise in Washtenaw County COVID-19 incidence during November 2020. These results provide valuable insights into the distinct transmission dynamics of SARS- CoV-2 among IHE populations and surrounding communities.

Did Clostridioides difficile Testing and Infection Rates Change During the COVID-19 Pandemic?

Background: The COVID-19 pandemic has underscored the importance of ongoing infection prevention efforts. Increased adherence to infection prevention recommendations, increased antibiotic use, improved hand hygiene, and correct donning and doffing of personal protective equipment may have influenced healthcare-associated infections (HAIs) in the United States during the pandemic. In this study, we investigated testing for Clostridioides difficile infection (CDI) and incidence during the initial surge of the pandemic. We hypothesized that strict adherence to contact precautions may have resulted in a decreased incidence of CDI in hospitalized patients during the first peak of the COVID-19 pandemic and that CDI testing may have increased even in the absence of directed diagnostic stewardship efforts. Methods: We conducted a single-center, retrospective, observational study at the Veterans’ Affairs (VA) Hospital in Ann Arbor, Michigan, between January 2019 and June 2020. We compared data on CDI tests from January 2019 through February 2020 to data from March 2020 (the admission of the first patient with COVID-19 at our institution) through June 2020. Pre-peak and peak periods were defined by confirmed cases in Washtenaw County. No novel diagnostic or CDI-focused stewardship interventions were introduced by the antimicrobial stewardship program during the study period. An interrupted time series analysis was performed using STATA version 16.1 software (StataCorp LLC, College Station, TX). Results: There were 6,525 admissions and 34,533 bed days between January 1, 2019, and June 30, 2020. Also, 900 enzyme immunoassay (EIA) tests were obtained and 104 positive cases of CDI were detected between January 2019 and June 2020. A statistically significant decrease in EIA tests occurred after March 1, 2020 (the COVID-19 peak in our region) compared to January 1, 2019–March 1, 2020 (Figure 1). After March 1, 2020, the number of EIA tests obtained decreased by 10.2 each month (95% CI, −18.7 to −1.7; P = .02). No statistically significant change in the incidence of CDI occurred. The use of antibiotics that were defined as high risk for CDI increased in the months of April–June 2020 (Figure 2). Conclusions: In this single-center study, we observed a stable incidence of CDI but decreased testing during the first peak of the COVID-19 pandemic. Understanding local HAI reporting is critical because changes in HAI reporting structures and exemptions during this period may have affected national reporting. Further research should be undertaken to investigate the effect of COVID-19 on other HAI reporting within the US healthcare system.Funding: NoDisclosures: None

Suicide attempt and intentional self-harm during the earlier phase of the COVID-19 pandemic in Washtenaw County, Michigan

ObjectiveDetermine the early impact of the COVID-19 pandemic on emergency department (ED) encounters for suicide attempt and intentional self-harm at a regional tertiary academic medical centre in Washtenaw County, Michigan, which is one of the wealthier and more diverse counties in the state.MethodsInterrupted time series analysis of daily ED encounters from October 2015 through October 2020 for suicide attempt and intentional self-harm (subject n=3002; 62% female; 78% Caucasian) using an autoregressive integrated moving average modelling approach.ResultsThere were 39.9% (95% CI 22.9% to 53.1%) fewer ED encounters for suicide attempt and intentional self-harm during the first 12 weeks of the COVID-19 pandemic (ie, on or after 10 March 2020, when the first cases of COVID-19 were identified in Michigan).ConclusionsFewer individuals sought emergency care for suicide-related behaviour during the earlier phase of the COVID-19 pandemic than expected when compared to prior years. This suggests initial outbreaks of COVID-19 and state of emergency executive orders did not increase suicide-related behaviour in the short term. More work is needed to determine long-term impacts of the COVID-19 pandemic on suicide-related behaviour and whether there are high-risk groups.

Abstract 352: Development of a Novel Tool for Data Abstraction From 911 Calls for Out-of-hospital Cardiac Arrest

Introduction: For out-of-hospital cardiac arrests (OHCAs) unwitnessed by emergency responders, contact with the 911 system provides the earliest point for consistent data collection. Building upon previous tools, we developed a 911 call data abstraction instrument and tested it to see if it reliably tracked key metrics from 911 calls for dispatch assisted CPR in order to guide quality initiatives for OHCA. Methods: Data abstractors applied this tool to a random sample of 23 emergency medical services (EMS)-confirmed, second-party, non-traumatic, non-overdose adult OHCAs occurring prior to first responder arrival from November 2017 to November 2019 in Washtenaw County, Michigan. For each call, data elements were collected by 2 independent reviewers. We focused on key variables: 1) whether the arrest was recognized by dispatch in eligible cases (n=23), 2) whether instructed compressions were provided in eligible cases (n=23), and 3) the 911-time-to-first-instructed-compression (n=11). To evaluate interrater reliability, we calculated kappa statistics for categorical variables and intraclass correlation coefficients (ICC) for continuous variables. Results: We included 23 calls with an average patient age of 64.2 (SD: 10.9) lasting an average of ~5 mins. Overall, 16 patients were men and 7 were women. Thirteen calls originated from private residences, 9 from a public place, and 1 could not be identified. We found that OHCA was recognized by dispatch in 18 of the 23 calls (78%). Reviewers reported instructed compressions occurred in 14 of 23 calls (61%). The median 911-time-to-first-instructed-compression of calls where consistent measurement was possible (n=11) was 197.5 seconds (IQR: 2:30.0-4:44.0). Among calls, kappa statistics for recognition of cardiac arrest and provision of instruction compressions was 1.00 (n=23) and 0.91 (n=23), respectively, while the ICC for time-to-first instructed compression was >0.99 (n=11). Conclusions: Reviewing 911 calls with this tool was capable of collecting reliable information from independent reviewers on key events including critically important times. Collection of these data is a critical first step for evaluating system performance to improve survival from OHCA.