Sickle Cell Disease (SCD) As a Risk for COVI19 Compared to Those without SCD Among Patients Admitted in a Large Urban Center, As Estimated By PCR Sars-v-2 Positive Vs Negative Testing

A diagnosis of SCD is considered to be at risk for COVD19. To further define the association between SCD and infection with COVID-19, we estimated risk, by comparing presence or absence of COVID19 infections in individuals with and without SCD admitted concurrently to a large urban health care facility (Grady Memorial Hospital, Atlanta, GA;960 beds, 5th largest public hospital in the US). Primary outcome was a positive or negative COVID-19 diagnosis as defined bySARS-CoV-2 PCR testing. A patient was considered to be COVID-19 positive if tested positive withSARS-CoV-2 PCR for the first time, anytime during the study period, irrespective of number of tests. A patient was considered to be COVID-19 negative if patient had no positive tests during the study period, and had one or moreSARS-CoV-2 PCR negative tests. For COVID19 positive patients, the admission of theSARS-CoV-2 PCR positive test was included in the analysis. For COVID19 negative patients, the first admission with aSARS-CoV-2 PCR negative test was considered for analysis. For this interim analysis, SCD was defined by ICD10 and registry data. Clinical diagnosis such as obesity and respiratory failure were defined by ICD10 coding. Data was obtained from quarterly centralized Epic EMR data extractions. Analysis of outcome of COVID19 positive vs negatives was stratified in four separate analysis: all admissions, ICU admissions, those with respiratory failure and those who died. Multivariate dichotomous logistic regression analyses modeled binary outcome effect of SCD, adjusted for age (<40 vs. > 40 years), sex at birth (females vs. males) and obesity (SAS version 9.4 was used for statistical analyses and overall significance level was set at 0.05). To ensure population homogeneity analysis was conducted on patient ages 20 to 60 years that were Black/African American and admitted from the Emergency Department for a short stay and/or the medicine service (variable interactions at a p<0.01). The study was approved by the institutional review board and by the hospital research oversight committee. Overall, between 3/23/2020 and 6/30/2020, 23697 patients were admitted once or more to Grady Memorial Hospital with one or more PCR sars-cov-2 test, of these 405 were patients with SCD (1.7%). Of the total, 2566 patients (10.8%) tested positive for COVID-19, and 48 patients with SCD (11.8%) were positive. Of 7041 (29.7%) were part of the study population, 332 (4.7%) where patients with SCD (hemoglobin [hb] SS/Sbeta0 =252, hbSC n=55, hbS beta thalassemia+ or hbS beta thalassemia undetermined n=21). Among patients without SCD, 36.3% were female, (n=2557) and among patients with SCD, 53.6% (n=178). The mean age of patients without SCD was: 51.1 years (standard deviation [std]) +/- 19.5 years), and for those with SCD: 35.0 years (std +/- 12.0 years). Results of univariate and multivariate analysis are presented in the table. In conclusion, in a Black/African American patients admitted from the Emergency Room for observation and/or the internal medicine service, when adjusted for age, gender and obesity, with SCD are at a significant increased risk for admissions with COVID-19 infection in general as well as ICU admission or admission with respiratory failures. Further studies can help articulate the risk associated with SCD as well as its potential interaction with other factors, with attention to confounders. [Formula presented] Disclosures: No relevant conflicts of interest to declare.

The Effects of Network Outages on User Experience in Augmented Reality Based Remote Collaboration - An Empirical Study

Augmented Reality (AR) applications can enable geographically distant users to collaborate using shared video feeds or interactive 3D holograms, and may be particularly useful in the socially distant context of the Covid-19 pandemic. However, a good user experience is key for their success and could be negatively impacted by network impairments, which are an inevitable occurrence in today's best-effort Internet. In this paper, we present the findings of an empirical user study, aimed at understanding the effects of network outages, on user experience and behavior, in a collaborative AR task. We highlight how network outages affected users in different ways depending on their role in the collaborative task, and how giving users explicit information about poor network conditions helped them deal with some of these negative effects. Furthermore, we report the strategies that users themselves adopted, to deal with outages, such as batching instructions, or shifting to a different spatial referencing style when communicating with their partners. Lastly, based on our findings, we present some design implications for future remote-collaborative AR applications. © 2021 Owner/Author.