Agreement of respiratory viruses' detection between nasopharyngeal swab and bronchoalveolar lavage in adults admitted for pneumonia: a retrospective study.

OBJECTIVES: The COVID-19 pandemic has highlighted the high diagnostic accuracy of the nasopharyngeal swab (including in intensive care unit (ICU) patients). This study aimed to compare nasopharyngeal swab and bronchoalveolar lavage (BAL) results for non-SARS-CoV-2 viruses in patients with suspected pneumonia. METHODS: A retrospective analysis was performed in one French academic hospital on consecutive adults from 2012 to 2018 and tested nasopharyngeal swab and BAL within 24 hours by using multiplex PCR. The agreement in pathogen detection between nasopharyngeal swab and BAL was evaluated. RESULTS: Patients were primarily men (n = 178/276, 64.5%), with a median age of 60 years (IQR: 51-68 years). Of the 276 patients, 169 (61%) were admitted to the ICU for acute respiratory distress. We detected at least one respiratory virus in 34.4% of the nasopharyngeal swabs (n = 95/276) and 29.0% of BAL (n = 80/276). Two or more viruses were detected in 2.5% of the nasopharyngeal swabs (n = 7/276) and 2.2% of BAL (n = 6/276). Rhinovirus/enteroviruses were the most frequently detected viral group in 10.2% (n = 29/285) of the nasopharyngeal swabs and 9.5% (n = 27/285) of BAL, followed by influenza A, detected in 5.6% (n = 16/285) of the nasopharyngeal swabs and 4.9% (n = 14/285) of BAL. Overall agreement was 83.7% (n = 231/276 (95% CI [78.7%, 87.7%])) (i.e. same pathogen or pathogen combination was identified in the nasopharyngeal swab and BAL for 231 patients). Rhinovirus/enterovirus (n = 29/231) and respiratory syncytial virus (n = 13/231) had the lowest agreement of 62.1% (n = 18/29 (95% CI [42.4%-78.7%])) and 61.5% (n = 8/13 (95% CI [32.3%-84.9%])), respectively). CONCLUSIONS: There was a good agreement between nasopharyngeal swabs and BAL in detecting respiratory viruses among adult patients with suspected pneumonia. However, these data still encourage BAL in the case of a negative nasopharyngeal swab.

SARS-CoV-2 exposures of healthcare workers from primary care, long-term care facilities and hospitals: a nationwide matched case-control study.

OBJECTIVES: This study assessed the roles of various exposures and personal protective equipment (PPE) use on healthcare workers' (HCWs) risk of COVID-19 working in primary care, long-term-care facilities or hospitals. METHODS: We conducted a matched case-control (1:1) study (10 April through 9 July 2021). Cases (HCWs with confirmed COVID-19) and controls (HCWs without any COVID-19-positive test or symptoms) were invited by E-mail to complete an online questionnaire on their exposures and PPE use over the 10-day period preceding inclusion. Risk factors were analysed using multivariable conditional logistic regression. RESULTS: A total of 2076 cases and 2076 matched controls were included. The analysis retained exposure to an infected person outside work (adjusted OR 19.9 (95% CI, 12.4-31.9)), an infected colleague (OR 2.26 (95% CI, 1.53-3.33)) or COVID-19 patients (OR 2.37 (95% CI, 1.66-3.40)), as independent predictors of COVID-19 in HCWs, while partial (OR 0.30 (95% CI, 0.22-0.40)) or complete (OR 0.19 (95% CI, 0.14-0.27)) immunisation was protective. Eye protection (OR 0.57 (95% CI, 0.37-0.87)) and wearing a gown (OR 0.58 (95% CI, 0.34-0.97)) for COVID-19 patient care were protective, while wearing an apron slightly increased the risk of infection (OR 1.47 (95% CI, 1.00-2.18)). Protection of N95 respirators and surgical face masks did not differ. Compared to medical professions, being a nurse (OR 3.79 (95% CI, 2.50-5.76)) or a nurse's aide (OR 9.08 (95% CI, 5.30-15.5)) was associated with COVID-19. Results were consistent across all healthcare settings. DISCUSSION: HCWs were more likely to get COVID-19 in their personal sphere than during occupational activities. Our results suggest that eye protection for HCWs during patient care should be actively promoted.

Nasopharyngeal and serological anti SARS-CoV-2 IgG/IgA responses in COVID-19 patients.

Background: The systemic antibody responses to SARS-CoV-2 in COVID-19 patients has been extensively studied. However, less is known about the mucosal responses in the upper airways, the site of initial SARS-CoV-2 replication. Methods: The IgG and IgA antibody responses were analysed in plasma and nasopharyngeal swabs from the first four confirmed COVID-19 patients in France. Two were pauci-symptomatic while two developed severe disease. We characterized their antibody profiles by using an in-house ELISA to detect antibodies directed against SARS-CoV-2 Nucleoprotein and Spike. Results: Anti-N IgG and IgA antibodies were detected in the NPS of severe patients only. The levels of antibodies in the plasma markedly differed amongst the patients. The most distinctive features are a strong anti-N IgG response in the severe patient who recovered, and a high anti-N IgA response specifically detected in the fatal case of COVID-19. Conclusions: Anti-N IgG and IgA antibodies are detected in NPS only for severe patients, with levels related to serological antibodies. The severe patients showed different antibody profiles in the plasma, notably regarding the IgA and IgG response to the N antigen, that may reflect different disease outcome. By contrast, pauci-symptomatic patients did not exhibit any mucosal antibodies in NSP, which is associated with a low or absent serological response against both N and S.

Added value of rapid respiratory syndromic testing at point of care versus central laboratory testing: a controlled clinical trial.

BACKGROUND: Virus-associated respiratory infections are in the spotlight with the emergence of SARS-CoV-2 and the expanding use of multiplex PCR (mPCR). The impact of molecular testing as a point-of-care test (POCT) in the emergency department (ED) is still unclear. OBJECTIVES: To compare the impact of a syndromic test performed in the ED as a POCT and in the central laboratory on length of stay (LOS), antibiotic use and single-room assignment. METHODS: From 19 November 2019 to 9 March 2020, adults with acute respiratory illness seeking care in the ED of a large hospital were enrolled, with mPCR performed with a weekly alternation in the ED as a POCT (week A) or in the central laboratory (week B). RESULTS: 474 patients were analysed: 275 during A weeks and 199 during B weeks. Patient characteristics were similar. The hospital LOS (median 7 days during week A versus 7 days during week B, P = 0.29), the proportion of patients with ED-LOS <1 day (63% versus 60%, P = 0.57) and ED antibiotic prescription (59% versus 58%, P = 0.92) were not significantly different. Patients in the POCT arm were more frequently assigned a single room when having a positive PCR for influenza, respiratory syncytial virus and metapneumovirus [52/70 (74%) versus 19/38 (50%) in the central testing arm, P = 0.012]. CONCLUSIONS: Syndromic testing performed in the ED compared with the central laboratory failed to reduce the LOS or antibiotic consumption in patients with acute respiratory illness, but was associated with an increased single-room assignment among patients in whom a significant respiratory pathogen was detected.

Inhibition of HECT E3 ligases as potential therapy for COVID-19.

SARS-CoV-2 is responsible for the ongoing world-wide pandemic which has already taken more than two million lives. Effective treatments are urgently needed. The enzymatic activity of the HECT-E3 ligase family members has been implicated in the cell egression phase of deadly RNA viruses such as Ebola through direct interaction of its VP40 Protein. Here we report that HECT-E3 ligase family members such as NEDD4 and WWP1 interact with and ubiquitylate the SARS-CoV-2 Spike protein. Furthermore, we find that HECT family members are overexpressed in primary samples derived from COVID-19 infected patients and COVID-19 mouse models. Importantly, rare germline activating variants in the NEDD4 and WWP1 genes are associated with severe COVID-19 cases. Critically, I3C, a natural NEDD4 and WWP1 inhibitor from Brassicaceae, displays potent antiviral effects and inhibits viral egression. In conclusion, we identify the HECT family members of E3 ligases as likely novel biomarkers for COVID-19, as well as new potential targets of therapeutic strategy easily testable in clinical trials in view of the established well-tolerated nature of the Brassicaceae natural compounds.