Hospital at home treatment with remdesivir for patients with COVID-19: real-life experience.

OBJECTIVES: Access and appropriateness of therapeutics for COVID-19 vary because of access or regulatory barriers, the severity of the disease, and for some therapies, the stage of the pandemic and circulating variants. Remdesivir has shown benefits in clinical recovery and is the treatment of choice for selected patients, both hospitalized and nonhospitalized, in main international guidelines. The use of remdesivir in alternatives to conventional hospitalization such as hospital at home (HaH) units remains incompletely explored. In this study, we aim to describe the real-life experience of outpatient remdesivir infusion for COVID-19 in a HaH unit. METHODS: We selected all the consecutive patients receiving remdesivir from a prospective cohort of 507 COVID-19 patients admitted at a HaH unit. Admission criteria included COVID-19 with a fraction of inspired oxygen requirement under 0.35 and respiratory rate under 22 rpm. Patients were daily assessed in person by a nurse and a physician. RESULTS: A total of 236 patients admitted at the HaH unit received remdesivir, 172 of whom were treated at home. Only 2% presented any adverse event related to the infusion, all of them mild. HaH saved 1416 day-beds, with only 5% of the patients requiring transfer back to the hospital. CONCLUSION: Remdesivir infusion in HaH units seems to be a safe and efficient alternative to conventional hospitalization for treating patients with nonsevere COVID-19.

Understanding the Excitation Wavelength Dependence and Thermal Stability of the SARS-CoV-2 Receptor-Binding Domain Using Surface-Enhanced Raman Scattering and Machine Learning

COVID-19 has cost millions of lives worldwide. The constant mutation of SARS-CoV-2 calls for thorough research to facilitate the development of variant surveillance. In this work, we studied the fundamental properties related to the optical identification of the receptor-binding domain (RBD) of SARSCoV-2 spike protein, a key component of viral infection. The Raman modes of the SARS-CoV-2 RBD were captured by surface enhanced Raman spectroscopy (SERS) using gold nanoparticles (AuNPs). The observed Raman enhancement strongly depends on the excitation wavelength as a result of the aggregation of AuNPs. The characteristic Raman spectra of RBDs from SARS-CoV-2 and MERS-CoV were analyzed by principal component analysis that reveals the role of secondary structures in the SERS process, which is corroborated with the thermal stability under laser heating. We can easily distinguish the Raman spectra of two RBDs using machine learning algorithms with accuracy, precision, recall, and F1 scores all over 95%. Our work provides an in-depth understanding of the SARS-CoV-2 RBD and paves the way toward rapid analysis and discrimination of complex proteins of infectious viruses and other biomolecules.

Accurate virus identification with interpretable Raman signatures by machine learning.

Rapid identification of newly emerging or circulating viruses is an important first step toward managing the public health response to potential outbreaks. A portable virus capture device, coupled with label-free Raman spectroscopy, holds the promise of fast detection by rapidly obtaining the Raman signature of a virus followed by a machine learning (ML) approach applied to recognize the virus based on its Raman spectrum, which is used as a fingerprint. We present such an ML approach for analyzing Raman spectra of human and avian viruses. A convolutional neural network (CNN) classifier specifically designed for spectral data achieves very high accuracy for a variety of virus type or subtype identification tasks. In particular, it achieves 99% accuracy for classifying influenza virus type A versus type B, 96% accuracy for classifying four subtypes of influenza A, 95% accuracy for differentiating enveloped and nonenveloped viruses, and 99% accuracy for differentiating avian coronavirus (infectious bronchitis virus [IBV]) from other avian viruses. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to virus identification. By correlating ML-selected salient Raman ranges with the signature ranges of known biomolecules and chemical functional groups­for example, amide, amino acid, and carboxylic acid­we verify that our ML model effectively recognizes the Raman signatures of proteins, lipids, and other vital functional groups present in different viruses and uses a weighted combination of these signatures to identify viruses.