Search

An outbreak of OXA-23-producing carbapenem-resistant Acinetobacter baumannii amongst ICU-patients with COVID-19 likely occurred by transmission through inanimate surfaces, potentially facilitated by a contaminated positioning pillow shared between patients. Subsequent rapid spread may have been caused by exposure to respiratory secretions contaminating healthcare worker's gloves and gowns during prone positioning., (© 2024. The Author(s).)

Background: The COVID-19 pandemic has placed unprecedented pressure on hospitals worldwide. In such a context of tension in healthcare systems, efficiently allocating hospital resources is a crucial aspect of crisis management. The aim of this study was to describe the clinical characteristics of readmitted patients and to determine risk factors for hospital readmission using data from the Swiss COVID-19 Hospital-Based Surveillance system (CH-SUR)., Methods: We investigated hospital readmissions within 60 days after discharge of patients from the CH-SUR surveillance system with a first hospitalisation between 1 December 2020 and 1 December 2021. Only community-acquired cases were considered. We compared the baseline characteristics of readmitted and non-readmitted patients. We performed univariable and multivariable logistic regression analyses to investigate the risk factors for hospital readmission., Findings: Of the 8039 eligible patients, 239 (3.0%, 95% confidence interval [CI] 2.6-3.3%) were readmitted to hospital within 60 days of discharge, with no significant variations observed over the study period; 80% of all readmissions occurred within 10 days of discharge of the index hospital stay. Based on our multivariable logistic regression models, factors increasing the odds of hospital readmission were age ≥65 years (odds ratio [OR] 1.63, 95% CI 1.24-2.15), male sex (OR 1.47, 95% CI 1.12-1.93), being discharged to home after first hospitalisation (OR 1.77, 95% CI 1.19-2.62), having oncological pathology (OR 1.82, 95% CI 1.27-2.61) and being immunosuppressed (OR 2.34, 95% CI 1.67-3.29)., Interpretations: Age, sex, cardiovascular diseases, oncological pathologies and immunosuppression were the main risk factors identified for hospital readmission.

The implementation of isolation precautions for patients with suspected Coronavirus Disease 2019 (COVID-19) and pending test results is resource intensive. Due to the limited availability of single-bed rooms at our institution, we isolated patients with suspected COVID-19 together with patients without suspected COVID-19 on-site in multiple-bed rooms until SARS-CoV-2-test results were available. We evaluated the likelihood of SARS-CoV-2 transmission to individuals sharing the room with patients isolated on-site. This observational study was performed at the University Hospital Basel, Switzerland, from 03/20 - 11/20. Secondary attack rates were compared between patients hospitalized in multiple-bed rooms and exposed to individuals subjected to on-site isolation precautions (on-site isolation group), and patients exposed to individuals initially not identified as having COVID-19, and not placed under isolation precautions until the diagnosis was suspected (control group). Transmission events were confirmed by whole-genome sequencing. Among 1,218 patients with suspected COVID-19, 67 (5.5%) tested positive for SARS-CoV-2. Of these, 21 were isolated on-site potentially exposing 27 patients sharing the same room. Median contact time was 12 h (interquartile range 7-18 h). SARS-CoV-2 transmission was identified in none of the patients in the on-site isolation group vs. 10/63 (15.9%) in the control group (p = 0.03). Isolation on-site of suspected COVID-19-patients in multiple-bed rooms avoided single-room occupancy and subsequent in-hospital relocation for many patients without confirmed SARS-CoV-2-infection. The absence of secondary transmission among the exposed patients in the on-site isolation group allows for assessment of the risk/benefit ratio of this strategy given the limitation of a small sample size., (© 2024. The Author(s).)

Background: In the initial phase of the SARS-CoV-2 pandemic, masking has been widely accepted in healthcare institutions to mitigate the risk of healthcare-associated infection. Evidence, however, is still scant and the role of masks in preventing healthcare-associated SARS-CoV-2 acquisition remains unclear.We investigated the association of variation in institutional mask policies with healthcare-associated SARS-CoV-2 infections in acute care hospitals in Switzerland during the BA.4/5 2022 wave., Methods: SARS-CoV-2 infections in hospitalized patients between June 1 and September 5, 2022, were obtained from the "Hospital-based surveillance of COVID-19 in Switzerland"-database and classified as healthcare- or community-associated based on time of disease onset. Institutions provided information regarding institutional masking policies for healthcare workers and other prevention policies. The percentage of healthcare-associated SARS-CoV-2 infections was calculated per institution and per type of mask policy. The association of healthcare-associated SARS-CoV-2 infections with mask policies was tested using a negative binominal mixed-effect model., Results: We included 2'980 SARS-CoV-2 infections from 13 institutions, 444 (15%) were classified as healthcare-associated. Between June 20 and June 30, 2022, six (46%) institutions switched to a more stringent mask policy. The percentage of healthcare-associated infections subsequently declined in institutions with policy switch but not in the others. In particular, the switch from situative masking (standard precautions) to general masking of HCW in contact with patients was followed by a strong reduction of healthcare-associated infections (rate ratio 0.39, 95% CI 0.30-0.49). In contrast, when compared across hospitals, the percentage of health-care associated infections was not related to mask policies., Conclusions: Our findings suggest switching to a more stringent mask policy may be beneficial during increases of healthcare-associated SARS-CoV-2 infections at an institutional level., (© 2024. The Author(s).)

Background: Personal protective equipment (PPE) protects healthcare workers and patients. Data on guideline compliance on how to dress (donning) or remove (doffing) PPE and the assistance among multiple participants (buddying) are limited. This study assesses the quality of donning, doffing, and buddying of PPE in a simulated medical emergency., Method: Physicians handling a simulated cardiac arrest of a COVID-19 patient. Adjacent to the victim, PPE was available. The appropriateness of PPE choice was assessed by using video recordings, with each individual participant being analyzed from the beginning of the simulation scenario from two perspectives regarding the selection of items during donning and doffing, hygiene aspects, time, and team support (buddying). The primary outcome was the number of participants being appropriately protected, defined as both wearing (a) all PPE items provided, and (b) all PPE items correctly at the time of first patient contact (FPC). Secondary outcomes included the timing of participants being appropriately protected. Statistical analysis was performed using SPSS (version 28). Mann-Whitney test, chi-square test, and linear regression analysis were performed as appropriate., Results: At first patient contact 21% (91/437) were correctly protected. One or more incorrect PPE items were found in 4% (19/437), whereas 61% (265/437) wore one or more PPE items incorrectly. In 14% (62/437), one or more PPE items were missing. The time interval between donning start and FPC was 66 (55-78) sec. Time to FPC was longer in correctly than in incorrectly protected participants 77 (66-87) vs. 64 (54-75) sec; p < 0.001) and decreased by 7 ± 2 s per PPE item omitted (P = 0.002). Correct doffing was observed in 192/345 (56%), while buddying occurred in 120 participants (27%), indicating that they either assisted other participants in some manner (verbally or physically) or received assistance themselves., Conclusions: Our findings imply a need for education in correct and timely PPE donning and doffing. Donning PPE as intended delayed FPC. This and the influence of buddying needs further investigation (German study register number DRKS00023184)., (© 2024. The Author(s).)

Introduction: Influenza infections are challenging to monitor at the population level due to many mild and asymptomatic cases and similar symptoms to other common circulating respiratory diseases, including COVID-19. Methods for tracking cases outside of typical reporting infrastructure could improve monitoring of influenza transmission dynamics. Influenza shedding into wastewater represents a promising source of information where quantification is unbiased by testing or treatment-seeking behaviours., Methods: We quantified influenza A and B virus loads from influent at Switzerland's three largest wastewater treatment plants, serving about 14% of the Swiss population (1.2 million individuals). We estimated trends in infection incidence and the effective reproductive number (Re) in these catchments during a 2021/22 epidemic and compared our estimates to typical influenza surveillance data., Results: Wastewater data captured the same overall trends in infection incidence as laboratory-confirmed case data at the catchment level. However, the wastewater data were more sensitive in capturing a transient peak in incidence in December 2021 than the case data. The Re estimated from the wastewater data was roughly at or below the epidemic threshold of 1 during work-from-home measures in December 2021 but increased to at or above the epidemic threshold in two of the three catchments after the relaxation of these measures. The third catchment yielded qualitatively the same results but with wider confidence intervals. The confirmed case data at the catchment level yielded comparatively less precise R&#95;e estimates before and during the work-from-home period, with confidence intervals that included one before and during the work-from-home period., Discussion: Overall, we show that influenza RNA in wastewater can help monitor nationwide influenza transmission dynamics. Based on this research, we developed an online dashboard for ongoing wastewater-based influenza surveillance in Switzerland.

BackgroundWomen are overrepresented among individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). Biological (sex) as well as sociocultural (gender) differences between women and men might account for this imbalance, yet their impact on PASC is unknown.AimWe assessed the impact of sex and gender on PASC in a Swiss population.MethodOur multicentre prospective cohort study included 2,856 (46% women, mean age 44.2 ± 16.8 years) outpatients and hospitalised patients with PCR-confirmed SARS-CoV-2 infection.ResultsAmong those who remained outpatients during their first infection, women reported persisting symptoms more often than men (40.5% vs 25.5% of men; p < 0.001). This sex difference was absent in hospitalised patients. In a crude analysis, both female biological sex (RR = 1.59; 95% CI: 1.41-1.79; p < 0.001) and a score summarising gendered sociocultural variables (RR = 1.05; 95% CI: 1.03-1.07; p < 0.001) were significantly associated with PASC. Following multivariable adjustment, biological female sex (RR = 0.96; 95% CI: 0.74-1.25; p = 0.763) was outperformed by feminine gender-related factors such as a higher stress level (RR = 1.04; 95% CI: 1.01-1.06; p = 0.003), lower education (RR = 1.16; 95% CI: 1.03-1.30; p = 0.011), being female and living alone (RR = 1.91; 95% CI: 1.29-2.83; p = 0.001) or being male and earning the highest income in the household (RR = 0.76; 95% CI: 0.60-0.97; p = 0.030).ConclusionSpecific sociocultural parameters that differ in prevalence between women and men, or imply a unique risk for women, are predictors of PASC and may explain, at least in part, the higher incidence of PASC in women. Once patients are hospitalised during acute infection, sex differences in PASC are no longer evident.

Competing Interests: VC-CC is member of the research committee of Society for Healthcare Epidemiology of America. All other authors declare no competing interests. We want to thank the scientific and public health experts, Ministerial delegations, and high-level representatives for their participation in the fifth Global Ministerial Summit on Patient Safety. We are particularly grateful to the Federal Office of Public Health of Switzerland, and Murielle Galas Haddad and Niccolò Buetti (Infection Control Programme, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland), for their contributions to organising the scientific programme of the Global Ministerial Summit related to the implications of the COVID-19 pandemic for patient safety.

Aims of the Study: Remdesivir has shown benefits against COVID-19. However, it remains unclear whether, to what extent, and among whom remdesivir can reduce COVID-19-related mortality. We explored whether the treatment response to remdesivir differed by patient characteristics., Methods: We analysed data collected from a hospital surveillance study conducted in 21 referral hospitals in Switzerland between 2020 and 2022. We applied model-based recursive partitioning to group patients by the association between treatment levels and mortality. We included either treatment (levels: none, remdesivir within 7 days of symptom onset, remdesivir after 7 days, or another treatment), age and sex, or treatment only as regression variables. Candidate partitioning variables included a range of risk factors and comorbidities (and age and sex unless included in regression). We repeated the analyses using local centring to correct the results for the propensity to receive treatment., Results: Overall (n = 21,790 patients), remdesivir within 7 days was associated with increased mortality (adjusted hazard ratios 1.28-1.54 versus no treatment). The CURB-65 score caused the most instability in the regression parameters of the model. When adjusted for age and sex, patients receiving remdesivir within 7 days of onset had higher mortality than those not treated in all identified eight patient groups. When age and sex were included as partitioning variables instead, the number of groups increased to 19-20; in five to six of those branches, mortality was lower among patients who received early remdesivir. Factors determining the groups where remdesivir was potentially beneficial included the presence of oncological comorbidities, male sex, and high age., Conclusions: Some subgroups of patients, such as individuals with oncological comorbidities or elderly males, may benefit from remdesivir.

We conducted a qualitative interview-based study to examine the perception of infection prevention and control (IPC) measures implemented during the COVID-19 pandemic among healthcare workers (HCWs) without patient contact in a tertiary academic care center. We compared these findings to those derived from interviews of HCWs with patient contact from the same institution using the same study design. The following main four themes were identified: (1) As for HCWs with patient contact, transparent communication strongly contributes to employees' sense of security. (2) Information on personal protective equipment (PPE) usage needs to be stratified according to different educational backgrounds and professions. (3) Consistency of IPC measures was positively perceived yet a desire for constant reminders to counteract the fatigue effect played a more significant role for HCWs without patient contact. (4) As compared to HCWs with patient contact, HCWs without patient contact preferred uniform digital training resources rather than more face-to-face training. This study shows that the needs of HCWs with and without patient contact differ and need to be considered in pandemic management., (© 2023. The Author(s).)

Background: We sought to decipher transmission pathways in healthcare-associated infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within our hospital by epidemiological work-up and complementary whole genome sequencing (WGS). We report the findings of the four largest epidemiologic clusters of SARS-CoV-2 transmission occurring during the second wave of the pandemic from 11/2020 to 12/2020., Methods: At the University Hospital Basel, Switzerland, systematic outbreak investigation is initiated at detection of any nosocomial case of SARS-CoV-2 infection, as confirmed by polymerase chain reaction, occurring more than five days after admission. Clusters of nosocomial infections, defined as the detection of at least two positive patients and/or healthcare workers (HCWs) within one week with an epidemiological link, were further investigated by WGS on respective strains., Results: The four epidemiologic clusters included 40 patients and 60 HCWs. Sequencing data was available for 70% of all involved cases (28 patients and 42 HCWs), confirmed epidemiologically suspected in house transmission in 33 cases (47.1% of sequenced cases) and excluded transmission in the remaining 37 cases (52.9%). Among cases with identical strains, epidemiologic work-up suggested transmission mainly through a ward-based exposure (24/33, 72.7%), more commonly affecting HCWs (16/24, 66.7%) than patients (8/24, 33.3%), followed by transmission between patients (6/33, 18.2%), and among HCWs and patients (3/33, 9.1%, respectively two HCWs and one patient)., Conclusions: Phylogenetic analyses revealed important insights into transmission pathways supporting less than 50% of epidemiologically suspected SARS-CoV-2 transmissions. The remainder of cases most likely reflect community-acquired infection randomly detected by outbreak investigation. Notably, most transmissions occurred between HCWs, possibly indicating lower perception of the risk of infection during contacts among HCWs., (© 2023. The Author(s).)

Aims of the Study: Wastewater-based epidemiology has contributed significantly to the comprehension of the dynamics of the current COVID-19 pandemic. Its additional value in monitoring SARS-CoV-2 circulation in the population and identifying newly arising variants independently of diagnostic testing is now undisputed. As a proof of concept, we report here correlations between SARS-CoV-2 detection in wastewater and the officially recorded COVID-19 case numbers, as well as the validity of such surveillance to detect emerging variants, exemplified by the detection of the B.1.1.529 variant Omicron in Basel, Switzerland., Methods: From July 1 to December 31, 2021, wastewater samples were collected six times a week from the inflow of the local wastewater treatment plant that receives wastewater from the catchment area of the city of Basel, Switzerland, comprising 273,075 inhabitants. The number of SARS-CoV-2 RNA copies was determined by reverse transcriptase-quantitative PCR. Spearman's rank correlation coefficients were calculated to determine correlations with the median seven-day incidence of genome copies per litre of wastewater and official case data. To explore delayed correlation effects between the seven-day median number of genome copies/litre wastewater and the median seven-day incidence of SARS-CoV-2 cases, time-lagged Spearman's rank correlation coefficients were calculated for up to 14 days. RNA extracts from daily wastewater samples were used to genotype circulating SARS-CoV-2 variants by next-generation sequencing., Results: The number of daily cases and the median seven-day incidence of SARS-CoV-2 infections in the catchment area showed a high correlation with SARS-CoV-2 measurements in wastewater samples. All correlations between the seven-day median number of genome copies/litre wastewater and the time-lagged median seven-day incidence of SARS-CoV-2 cases were significant (p<0.001) for the investigated lag of up to 14 days. Correlation coefficients declined constantly from the maximum of 0.9395 on day 1 to the minimum of 0.8016 on day 14. The B.1.1.529 variant Omicron was detected in wastewater samples collected on November 21, 2021, before its official acknowledgement in a clinical sample by health authorities., Conclusions: In this proof-of-concept study, wastewater-based epidemiology proved a reliable and sensitive surveillance approach, complementing routine clinical testing for mapping COVID-19 pandemic dynamics and observing newly circulating SARS-CoV-2 variants.

Background: Inflammatory biomarkers are associated with severity of coronavirus disease 2019 (COVID-19). However, direct comparisons of their utility in COVID-19 versus other respiratory infections are largely missing., Objective: We aimed to investigate the prognostic utility of various inflammatory biomarkers in COVID-19 compared to patients with other respiratory infections., Materials and Methods: Patients presenting to the emergency department with symptoms suggestive of COVID-19 were prospectively enrolled. Levels of Interleukin-6 (IL-6), c-reactive protein (CRP), procalcitonin, ferritin, and leukocytes were compared between COVID-19, other viral respiratory infections, and bacterial pneumonia. Primary outcome was the need for hospitalisation, secondary outcome was the composite of intensive care unit (ICU) admission or death at 30 days., Results: Among 514 patients with confirmed respiratory infections, 191 (37%) were diagnosed with COVID-19, 227 (44%) with another viral respiratory infection (viral controls), and 96 (19%) with bacterial pneumonia (bacterial controls). All inflammatory biomarkers differed significantly between diagnoses and were numerically higher in hospitalized patients, regardless of diagnoses. Discriminative accuracy for hospitalisation was highest for IL-6 and CRP in all three diagnoses (in COVID-19, area under the curve (AUC) for IL-6 0.899 [95%CI 0.850-0.948]; AUC for CRP 0.922 [95%CI 0.879-0.964]). Similarly, IL-6 and CRP ranged among the strongest predictors for ICU admission or death at 30 days in COVID-19 (AUC for IL-6 0.794 [95%CI 0.694-0.894]; AUC for CRP 0.807 [95%CI 0.721-0.893]) and both controls. Predictive values of inflammatory biomarkers were generally higher in COVID-19 than in controls., Conclusion: In patients with COVID-19 and other respiratory infections, inflammatory biomarkers harbour strong prognostic information, particularly IL-6 and CRP. Their routine use may support early management decisions., Competing Interests: RT has received speaker honoraria/consulting honoraria from Abbott, Amgen, Astra Zeneca, Roche, Siemens, Singulex, and Thermo Scientific BRAHMS, outside the submitted work. GK has received consultant fees from Janssen, outside the submitted work. Authors not named here have disclosed no competing interests. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Aims of the Study: In the global COVID-19 pandemic, female sex is associated with comparable infection rates but better outcome. However, most studies lacked appropriate controls. We investigated whether these sex disparity findings are specific to patients with COVID-19 or generalizable to patients presenting to the emergency room (ER) with similar symptoms but no COVID-19., Methods: In this prospective cohort study, consecutive patients presenting with symptoms suggestive of COVID-19 were recruited at the ER of the University Hospital Basel, Switzerland from March to June 2020. Patients were categorized as SARS-CoV-2 positive (cases) or negative (controls) based on nasopharyngeal PCR swab tests. The final clinical diagnosis was determined for all patients. The primary outcome was a composite of intensive care admission, rehospitalization for respiratory distress and all-cause death within 30 days. We used Kaplan-Meier curves and Cox proportional hazards models to explore associations between sex and outcomes., Results: Among 1,081 consecutive ER patients, 191 (18%) tested positive for SARS-CoV-2, with an even sex distribution (17.9% female vs. 17.5% male, p = 0.855). In COVID-19 patients, female sex was associated with lower risk of hospitalization (51% vs. 66%, p = 0.034), lower necessity of haemodynamic support (8% vs. 20%, p = 0.029), lower rates of intubation (10% vs. 21%, p = 0.037) and the primary outcome (18% vs. 31%, p = 0.045; age-adjusted HR 0.536, 95%CI 0.290-0.989, p = 0.046) compared with male sex. Sex disparities were most prominent in patients ≥55 years (HR for composite primary outcome in women 0.415, 95%CI 0.201-0.855, p = 0.017). In contrast to the COVID-19 patients, no sex-specific differences in outcomes were observed in the unselected overall control group (age-adjusted HR 0.844, 95%CI 0.560-1.273, p = 0.419) or in a subgroup of controls with upper respiratory tract infections or pneumonia (age-adjusted HR 0.840, 95%CI 0.418-1.688, p = 0.624)., Conclusion: In this unselected, consecutive cohort study at a tertiary hospital in Switzerland, female sex is associated with better outcome in patients presenting to the ER with COVID-19. These sex disparities seem to be at least partly specific to COVID-19, as they were not observed in comparable controls.

Scope: This guideline addresses the indications for direct testing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in asymptomatic individuals in health care facilities, with the aim to prevent SARS-CoV-2 transmissions in these settings. The benefit of testing asymptomatic individuals to create a safe environment for patients and health care workers must be weighed against potential unintended consequences, including delaying necessary treatments owing to false positive results and lower quality of care owing to strict isolation measures., Methods: A total of nine PICOs (population, intervention, comparison, outcome) on the topic of testing asymptomatic individuals was selected by the panel members. Subsequently, a literature search for existing guidelines and systematic reviews was performed on PubMed, Epistemonikos, and RecMap using relevant filters available in each database. Data on article/recommendation type, setting, target population, intervention, and quality of the evidence were extracted. Credibility of the systematic reviews was evaluated using the AMSTAR tool, and level of agreement with available recommendation was evaluated with the AGREE II score. Because the evidence available from systematic reviews was deemed insufficiently updated to formulate relevant recommendations, an additional search targeting relevant guidance documents from major public health institutions and original studies was performed. Provisional recommendations were discussed via web conferences until agreement was reached, and final recommendations were formulated according to the GRADE approach., Recommendations: Recommendations were formulated regarding systematic testing in asymptomatic individuals upon admission to a health care setting, during hospital stay, before elective procedures, and before scheduled nonsurgical procedures. Moreover, recommendations regarding testing of asymptomatic visitors, personal caregivers, and health care workers in health care facilities were presented. Recommendations also were given on contact tracing in asymptomatic patients or health care workers and the possibility of a negative screening test to shorten the quarantine period. Furthermore, if applicable, recommendations were specified to transmission rate and vaccination coverage., (Copyright © 2022 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Protecting healthcare workers (HCWs) from exposure to SARS-CoV-2 during patient care is central to managing the current pandemic. Higher levels of trust in personal protective equipment (PPE) and infection prevention and control (IPC) strategies have been previously related to lower levels of emotional exhaustion, yet little is known on how to achieve such a perception of safety. We thus sought to identify institutional actions, strategies and policies related to HCWs' safety perception during the early phase of the pandemic at a tertiary care center in Switzerland by interviewing HCWs from different clinics, professions, and positions., Methods: For this qualitative study, 36 face-to-face semi-structured interviews were performed. Interviews were based on a guide that addressed the perception of institutional strategies and policies during the first phase of the pandemic in March 2020. The participants included doctors (n = 19) and nurses (n = 17) in senior and non-senior positions from eight clinics in the University Hospital Basel, Switzerland, all involved in patient care. All interviews were audio-recorded and transcribed verbatim. Data were analyzed using qualitative content analysis and organized using MAXQDA (VERBI Software GmbH, Berlin)., Findings: Five recurring themes were identified to affect HCWs' perception of their safety during the SARS-CoV-2 pandemic: (1) transparency and clarity of information, (2) communication on the availability of PPE (with the provision of information alone increasing the feeling of safety even if supplies of PPE were reported as low), (3) uniformity and consistency of guidelines, (4) digital resources to support face-to-face teaching (although personal information transfer is still being considered superior in terms of strengthening safety perception) and (5) support and appreciation for the work performed., Conclusions: This study identifies institutional policies and actions influencing HCWs' safety perception during the first wave of the COVID-19 pandemic, the most important of which is the factor of transparent communication. This knowledge reveals potential areas of action critical to improving preparedness and management in hospitals faced with an infectious disease threat., (© 2022. The Author(s).)

Study Aims: To quantify mimics and chameleons of coronavirus disease 2019 (COVID-19), to analyse the diagnostic accuracy of the triage protocol, and to describe the resulting groups of mimics and chameleons - including their presenting symptoms and final diagnoses., Methods: Diagnostic accuracy study including all adult patients tested for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) at the emergency department of the University Hospital Basel, Switzerland during the first wave of pandemic in spring 2020. Diagnostic accuracy of triage was determined by calculating sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratio. Triage to the group of suspected (+) and not suspected (-) COVID-19 was considered the index test, whereas a SARS-CoV-2 polymerase chain reaction test result was used as reference standard. Mimics were defined as false positives and chameleons as false negatives., Results: Of 2898 patients included in the analysis, 191 were true positives, 895 were false positives (mimics), 9 were false negatives (chameleons) and 1803 were true negatives. This resulted in a sensitivity of 0.95 (95% confidence interval [CI] 0.92-0.98) and a specificity of 0.67 (95% CI 0.65-0.69) for standardised triage. Among mimics, the main categories of final diagnoses were other infections (n = 513, 57.3%), cardiovascular diseases (excluding cerebrovascular) (n = 125, 14%), and non-infectious diseases of the respiratory system (n = 84, 9.4%). Fever (n = 357, 39.9% vs n = 104, 54.5%), cough (n = 466, 52.1% vs n = 126 66%), and smell or taste dysfunction (n = 60, 6.7% vs n = 24, 12.6%) were less frequently observed in mimics than in COVID-19 patients. Eight of nine COVID-19 chameleons presented with either nonspecific complaints (weakness and/or fatigue) or gastrointestinal symptoms., Conclusion: The quantitative assessment of COVID-19 mimics and chameleons showed a high prevalence of mimics. Clinical differentiation between true positives and false positives is not feasible due to largely overlapping symptoms. Prevalence of chameleons was very low.

Background: When the periods of time during and after the first wave of the ongoing SARS-CoV-2/COVID-19 pandemic in Europe are compared, the associated COVID-19 mortality seems to have decreased substantially. Various factors could explain this trend, including changes in demographic characteristics of infected persons and the improvement of case management. To date, no study has been performed to investigate the evolution of COVID-19 in-hospital mortality in Switzerland, while also accounting for risk factors., Methods: We investigated the trends in COVID-19-related mortality (in-hospital and in-intermediate/intensive-care) over time in Switzerland, from February 2020 to June 2021, comparing in particular the first and the second wave. We used data from the COVID-19 Hospital-based Surveillance (CH-SUR) database. We performed survival analyses adjusting for well-known risk factors of COVID-19 mortality (age, sex and comorbidities) and accounting for competing risk., Results: Our analysis included 16,984 patients recorded in CH-SUR, with 2201 reported deaths due to COVID-19 (13.0%). We found that overall in-hospital mortality was lower during the second wave of COVID-19 than in the first wave (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.63- 0.78; p <0.001), a decrease apparently not explained by changes in demographic characteristics of patients. In contrast, mortality in intermediate and intensive care significantly increased in the second wave compared with the first wave (HR 1.25, 95% CI 1.05-1.49; p = 0.029), with significant changes in the course of hospitalisation between the first and the second wave., Conclusion: We found that, in Switzerland, COVID-19 mortality decreased among hospitalised persons, whereas it increased among patients admitted to intermediate or intensive care, when comparing the second wave to the first wave. We put our findings in perspective with changes over time in case management, treatment strategy, hospital burden and non-pharmaceutical interventions. Further analyses of the potential effect of virus variants and of vaccination on mortality would be crucial to have a complete overview of COVID-19 mortality trends throughout the different phases of the pandemic.

Commercially available SARS-CoV-2-directed antibody assays may assist in diagnosing past exposure to SARS-CoV-2 antigens. We cross-compared the following eight immunoassays detecting antibodies against SARS-CoV-2 nucleocapsid (N) or spike (S) antigens in three cohorts consisting of 859 samples from 622 patients: (#1) EDI novel coronavirus COVID-19 (Epitope), (#2) RecomWell SARS-CoV-2 (Mikrogen), (#3) COVID-19 ELISA (VirCell), (#4) Elecsys anti-SARS-CoV-2 N (Roche), (#5) Liaison SARS-CoV-2 S1/S2 (DiaSorin), (#6) anti-SARS-CoV-2 ELISA (EuroImmun), (#7) Elecsys anti-SARS-CoV-2 S (Roche), and (#8) Liaison SARS-CoV-2 TrimericS (DiaSorin). In cross-sectional cohort 1 (68 sera from 38 patients with documented SARS-CoV-2 infection), agreement between assays #1 to #6 ranged from 75% to 93%, whereby discordance mostly resulted from N-based assays #1 to #4. In cross-sectional cohort 2 (510 sera from 510 patients; 56 documented, 454 unknown SARS-CoV-2 infection), assays #4 to #6 were analyzed further together with assays #7 and #8, revealing 94% concordance (44 [9%] positives and 485 [85%] negatives). Discordance was highest within 2 weeks after SARS-CoV-2/COVID-19 diagnosis and confirmed in the longitudinal cohort 3 (281 sera from 74 COVID-19 patients), using assays #4, #6, #7, and #8. Subanalysis of 20 (27%) initially seronegative cohort 3 patients revealed assay-dependent 50% and 90% seroconversion rates after 8 to 11 days and 14 to 18 days, respectively. Increasing SARS-CoV-2 antibodies were significantly associated with declining levels of viral loads, lactate dehydrogenase, interleukin-6, and C-reactive protein and preceded clearance of SARS-CoV-2 detection in the upper respiratory tract by approximately 1 week. SARS-CoV-2-specific antibody assays show substantial agreement, but interpretation of qualitative and semiquantitative results depends on the time elapsed postdiagnosis and the choice of viral antigen. Mounting of systemic SARS-CoV-2-specific antibodies may predict recovery from viral injury and clearance of mucosal replication.

Background: As clinical signs of COVID-19 differ widely among individuals, from mild to severe, the definition of risk groups has important consequences for recommendations to the public, control measures and patient management, and needs to be reviewed regularly., Aim: The aim of this study was to explore risk factors for in-hospital mortality and intensive care unit (ICU) admission for hospitalised COVID-19 patients during the first epidemic wave in Switzerland, as an example of a country that coped well during the first wave of the pandemic., Methods: This study included all (n = 3590) adult polymerase chain reaction (PCR)-confirmed hospitalised patients in 17 hospitals from the hospital-based surveillance of COVID-19 (CH-Sur) by 1 September 2020. We calculated univariable and multivariable (adjusted) (1) proportional hazards (Fine and Gray) survival regression models and (2) logistic regression models for in-hospital mortality and admission to ICU, to evaluate the most common comorbidities as potential risk factors., Results and Discussion: We found that old age was the strongest factor for in-hospital mortality after having adjusted for gender and the considered comorbidities (hazard ratio [HR] 2.46, 95% confidence interval [CI] 2.33&minus;2.59 and HR 5.6 95% CI 5.23&minus;6 for ages 65 and 80 years, respectively). In addition, male gender remained an important risk factor in the multivariable models (HR 1.47, 95% CI 1.41&minus;1.53). Of all comorbidities, renal disease, oncological pathologies, chronic respiratory disease, cardiovascular disease (but not hypertension) and dementia were also risk factors for in-hospital mortality. With respect to ICU admission risk, the pattern was different, as patients with higher chances of survival might have been admitted more often to ICU. Male gender (OR 1.91, 95% CI 1.58&minus;2.31), hypertension (OR&nbsp; 1.3, 95% CI 1.07&minus;1.59) and age 55&ndash;79 years (OR 1.15, 95% CI 1.06&minus;1.26) are risk factors for ICU admission. Patients aged 80+ years, as well as patients with dementia or with liver disease were admitted less often to ICU., Conclusion: We conclude that increasing age is the most important risk factor for in-hospital mortality of hospitalised COVID-19 patients in Switzerland, along with male gender and followed by the presence of comorbidities such as renal diseases, chronic respiratory or cardiovascular disease, oncological malignancies and dementia. Male gender, hypertension and age between 55 and 79 years are, however, risk factors for ICU admission. Mortality and ICU admission need to be considered as separate outcomes when investigating risk factors for pandemic control measures and for hospital resources planning.

The first case of SARS-CoV-2 in Basel, Switzerland was detected on February 26th 2020. We present a phylogenetic study to explore viral introduction and evolution during the exponential early phase of the local COVID-19 outbreak from February 26th until March 23rd. We sequenced SARS-CoV-2 naso-oropharyngeal swabs from 746 positive tests that were performed at the University Hospital Basel during the study period. We successfully generated 468 high quality genomes from unique patients and called variants with our COVID-19 Pipeline (COVGAP), and analysed viral genetic diversity using PANGOLIN taxonomic lineages. To identify introduction and dissemination events we incorporated global SARS-CoV-2 genomes and inferred a time-calibrated phylogeny. Epidemiological data from patient questionnaires was used to facilitate the interpretation of phylogenetic observations. The early outbreak in Basel was dominated by lineage B.1 (83·6%), detected first on March 2nd, although the first sample identified belonged to B.1.1. Within B.1, 68·2% of our samples fall within a clade defined by the SNP C15324T ('Basel cluster'), including 157 identical sequences at the root of the 'Basel cluster', some of which we can specifically trace to regional spreading events. We infer the origin of B.1-C15324T to mid-February in our tri-national region. The other genomes map broadly over the global phylogenetic tree, showing several introduction events from and/or dissemination to other regions of the world via travellers. Family transmissions can also be traced in our data. A single lineage variant dominated the outbreak in the Basel area while other lineages, such as the first (B.1.1), did not propagate. A mass gathering event was the predominant initial source of cases, with travel returners and family transmissions to a lesser extent. We highlight the importance of adding specific questions to epidemiological questionnaires, to obtain data on attendance of large gatherings and their locations, as well as travel history, to effectively identify routes of transmissions in up-coming outbreaks. This phylogenetic analysis in concert with epidemiological and contact tracing data, allows connection and interpretation of events, and can inform public health interventions. Trial Registration: ClinicalTrials.gov NCT04351503., Competing Interests: The authors have declared that no competing interests exist.

There is emerging evidence for multifarious neurological manifestations of coronavirus disease 2019 (COVID-19), but little is known regarding whether they reflect structural damage to the nervous system. Serum neurofilament light chain (sNfL) is a specific biomarker of neuronal injury. We measured sNfL concentrations of 29 critically ill COVID-19 patients, 10 critically ill non-COVID-19 patients, and 259 healthy controls. After adjusting for neurological comorbidities and age, sNfL concentrations were higher in patients with COVID-19 versus both comparator groups. Higher sNfL levels were associated with unfavorable short-term outcome, indicating that neuronal injury is common and pronounced in critically ill patients. ANN NEUROL 2021;89:610-616., (© 2020 American Neurological Association.)

Objective: The pandemic of coronavirus disease (COVID-19) has rapidly spread globally and infected millions of people. The prevalence and prognostic impact of dysnatremia in COVID-19 is inconclusive. Therefore, we investigated the prevalence and outcome of dysnatremia in COVID-19., Design: The prospective, observational, cohort study included consecutive patients with clinical suspicion of COVID-19 triaged to a Swiss Emergency Department between March and July 2020., Methods: Collected data included clinical, laboratory and disease severity scoring parameters on admission. COVID-19 cases were identified based on a positive nasopharyngeal swab test for SARS-CoV-2, patients with a negative swab test served as controls. The primary analysis was to assess the prognostic impact of dysnatremia on 30-day mortality using a cox proportional hazard model., Results: 172 (17%) cases with COVID-19 and 849 (83%) controls were included. Patients with COVID-19 showed a higher prevalence of hyponatremia compared to controls (28.1% vs 17.5%, P < 0.001); while comparable for hypernatremia (2.9% vs 2.1%, P = 0.34). In COVID-19 but not in controls, hyponatremia was associated with a higher 30-day mortality (HR: 1.4, 95% CI: 1.10-16.62, P = 0.05). In both groups, hypernatremia on admission was associated with higher 30-day mortality (COVID-19 - HR: 11.5, 95% CI: 5.00-26.43, P < 0.001; controls - HR: 5.3, 95% CI: 1.60-17.64, P = 0.006). In both groups, hyponatremia and hypernatremia were significantly associated with adverse outcome, for example, intensive care unit admission, longer hospitalization and mechanical ventilation., Conclusion: Our results underline the importance of dysnatremia as predictive marker in COVID-19. Treating physicians should be aware of appropriate treatment measures to be taken for patients with COVID-19 and dysnatremia.

The proportion of asymptomatic carriers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains elusive and the potential benefit of systematic screening during the SARS-CoV-2-pandemic is controversial. We investigated the proportion of asymptomatic inpatients who were identified by systematic screening for SARS-CoV-2 upon hospital admission. Our analysis revealed that systematic screening of asymptomatic inpatients detects a low total number of SARS-CoV-2 infections (0.1%), questioning the cost-benefit ratio of this intervention. Even when the population-wide prevalence was low, the proportion of asymptomatic carriers remained stable, supporting the need for universal infection prevention and control strategies to avoid onward transmission by undetected SARS-CoV-2-carriers during the pandemic.

Background: Elevated D-dimer levels have been observed in COVID-19 and are of prognostic value, but have not been compared to an appropriate control group., Methods: Observational cohort study including emergency patients with suspected or confirmed COVID-19. Logistic regression defined the association of D-dimer levels, COVID-19 positivity, age, and gender with 30-day-mortality., Results: 953 consecutive patients (median age 58, 43% women) presented with suspected COVID-19: 12 (7.4%) patients with confirmed SARS-CoV-2-infection died, compared with 28 (3.5%) patients without SARS-CoV-2-infection. Overall, most (56%) patients had elevated D-dimer levels (≥0.5mg/l). Age (OR 1.07, CI 1.05-1.10), D-dimer levels ≥0.5mg/l (OR 2.44, CI 0.98-7.39), and COVID-19 (OR 2.79, CI 1.28-5.80) were associated with 30-day-mortality., Conclusion: D-dimer levels are effective prognosticators in both patient groups.