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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues its largely aseasonal spread with millions of cases per year. Highly sensitive, point-of-care testing is critical for rapid detection of coronavirus disease 2019 (COVID-19) cases and initiation of antiviral therapy to avert adverse health outcomes and reduce onward transmission of the virus. While hundreds of COVID-19 diagnostics received emergency use authorization from the FDA during the pandemic, significantly fewer have navigated the course to FDA clearance or approval. Here, we determined the clinical performance of the Cepheid Xpert Xpress CoV-2 plus for detection of SARS-CoV-2 in 3,750 anterior nasal swab (NS) specimens and nasopharyngeal swab (NPS) from 32 sites in comparison to the FDA-authorized BioFire Respiratory Panel 2.1. Three-quarters of specimens collected were tested on the Xpert Xpress CoV-2 plus in the point-of-care setting. Overall positive percent agreement (PPA) was 98.1% (95% CI: 96.7%-98.9%) and negative percent agreement (NPA) was 98.3% (97.7%-98.7%). Performance of the Xpert Xpress CoV-2 plus was slightly improved in NS compared to NPS specimens, with PPA of 99.3% versus 97.0% (Fisher's exact test, P = 0.06) and NPA of 98.3% versus 98.2% ( P = 0.89), respectively. Assay PPA was similar between untrained and trained users (98.7% vs 97.3%, P = 0.75), while NPA was slightly improved for untrained users (99.0% vs 97.6%, P = 0.0003). This study showed that Cepheid Xpert Xpress COV-2 plus is highly sensitive and specific/has high PPA and NPA for detection of SARS-CoV-2 from both NS and NPS specimens., Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to cause millions of infections and tens of thousands of deaths per year in the United States. While the FDA authorized hundreds of SARS-CoV-2 tests during the public health emergency, significantly fewer have made the transition to being cleared or approved. There continues to be a need for FDA-authorized point-of-care SARS-CoV-2 testing that can be performed by untrained users. We conducted a large prospective study of the Cepheid Xpert Xpress CoV-2 plus test for detection of SARS-CoV-2 in both nasal and nasopharyngeal swabs by trained and untrained users. The assay demonstrated excellent clinical performance characteristics and, as a result of this study, was cleared by the FDA., Competing Interests: This study was supported by Cepheid. A.L.G. reports contract testing from Abbott, Novavax, Pfizer, Janssen, and Hologic, as well as research support from Gilead, outside of the described work. D.R., X.L., and A.R. are employees of Cepheid.

Background: Vancomycin is often required to treat methicillin-resistant Staphylococcus aureus bacteremia in children. Treatment failure occurs in up to 50% of adults and is associated with a 24-hour area under the curve/minimum inhibitory concentration (AUC24h/MIC) <400. We sought to identify patient factors associated with vancomycin AUC and whether AUC24h/MIC <400 was predictive of treatment failure in children., Methods: Hospitalized children younger than 18 years with methicillin-resistant Staphylococcus aureus bacteremia receiving vancomycin were included in a retrospective cohort study. AUC24h was calculated using a validated pharmacokinetic model. Factors such as age, sex, underlying conditions, presence of foreign bodies, patient site of infection, and markers of illness severity were examined for an association with vancomycin AUC, and AUC24h/MIC was evaluated for an association with treatment failure., Results: Subjects requiring intensive care unit support were significantly more likely to have higher vancomycin AUC24h and AUCavg than those subjects not needing intensive care unit support. Although vancomycin serum trough concentrations are predictive of vancomycin AUC, suboptimal exposure of vancomycin occurred in almost 20% of subjects despite trough concentrations within the target range. A relationship between vancomycin AUC24h/MIC and treatment failure could not be established., Conclusions: To ensure optimal AUC/MIC pharmacodynamic index, especially in critically ill patients, estimation of the AUC is critical.