Airborne SARS-CoV-2 RNA excretion by patients with COVID-19 on different oxygen-delivery systems: a prospective observational study.

BACKGROUND: Concerns persist regarding the risk of airborne SARS-CoV-2 transmission by patients with COVID-19 on various modalities of oxygen therapy, such as high-flow nasal cannula (HFNC). AIM: We aimed to compare the presence of airborne RNA in air samples between groups of patients with COVID-19 on different oxygen-delivery systems. We also explored factors that were associated with SARS-CoV-2 RNA positivity in air samples. RESULTS: Air samples were positive for SARS-CoV-2 RNA in three of 39 patients (8%) on HFNC, 0 of 13 (0%) on masks, versus five of 20 (25%) on nasal cannula. Odds ratio for air sample positivity was 0.52 (95% confidence interval (CI) 0.11-2.34) when comparing HFNC vs non-HFNC group, and 5.78 (1.24-27.01) for nasal cannula vs non-nasal cannula group. Patients with positive air samples in comparison with those with negative air samples were sampled earlier after symptoms onset (median: 7 vs 10 days; P=0.04) and had lower Ct values of diagnostic nasopharyngeal samples (median: 22 vs 26; P=0.02). CONCLUSIONS: Air sample positivity was not related to oxygen support device but to viral load. These data suggest that the use of personal protection equipment should be based on risk management according to viral load rather than oxygen support device.

Airborne SARS-CoV-2 in home and hospital environments investigated with a high-powered air sampler.

BACKGROUND: The initial aim was to study the effects of face masks worn by recently infected individuals on the airborne spread of SARS-CoV-2, but findings motivated us to proceed with comparing the presence of SARS-CoV-2 in air samples near infected individuals at home with those near infected intensive care unit (ICU) patients. AIM: To assess the presence of SARS-CoV-2 in the air of homes of infected individuals and in ICU rooms of critically ill patients with COVID-19 who were undergoing different forms of potential aerosol-generating medical procedures. METHODS: A high-volume air sampler method was developed that used a household vacuum cleaner with surgical face masks serving as sample filters. SARS-CoV-2 RNA was harvested from these filters and analysed by polymerase chain reaction. Fog experiments were performed to visualize the airflow around the air sampler. Air samples were acquired in close proximity of infected individuals, with or without wearing face masks, in their homes. Environmental air samples remote from these infected individuals were also obtained, plus samples near patients in the ICU undergoing potential aerosol-generating medical procedures. FINDINGS: Wearing a face mask resulted in a delayed and reduced flow of the fog into the air sampler. Face masks worn by infected individuals were found to contain SARS-CoV-2 RNA in 71% of cases. SARS-CoV-2 was detected in air samples regardless of mask experiments. The proportion of positive air samples was higher in the homes (29/41; 70.7%) than in the ICU (4/17; 23.5%) (P < 0.01). CONCLUSION: SARS-CoV-2 RNA could be detected in air samples by using a vacuum cleaner based air sampler method. Air samples in the home environment of recently infected individuals contained SARS-CoV-2 RNA nearly three times more frequently by comparison with those obtained in ICU rooms during potential aerosol-generating medical procedures.

Anti-infectious decontamination strategies in Dutch intensive care units: A survey study on contemporary practice and heterogeneity.

PURPOSE: Despite increasing evidence and updated national guidelines, practice of anti-infectious strategies appears to vary in the Netherlands. This study aimed to determine the variation of current practices of anti-infectious strategies in Dutch ICUs. MATERIALS AND METHODS: In 2018 and 2019 an online survey of all Dutch ICUs was conducted with detailed questions on their anti-infectious strategies. RESULTS: 89% (63 of 71) of the Dutch ICUs responded to the online survey. The remaining ICUs were contacted by telephone. 47 (66%) of the Dutch ICUs used SDD, 14 (20%) used SOD and 10 (14%) used neither SDD nor SOD. Within these strategies considerable heterogeneity was observed in the start criteria of SDD/SOD, the regimen adjustments based on microbiological surveillance and the monitoring of the interventions. CONCLUSIONS: The proportion of Dutch ICUs applying SDD or SOD increased over time. Considerable heterogeneity in the regimens was reported. The impact of the observed differences within SDD and SOD practices on clinical outcome remains to be explored.

Trends in SARS-CoV-2 seroprevalence amongst urban paediatric patients compared with a nationwide cohort in the Netherlands.

Objectives: The extent of SARS-CoV-2 infection amongst children and their role in transmission remains unclear. Therefore, we aimed to estimate the SARS-CoV-2 antibody seroprevalence amongst children who presented to our hospital for non-COVID-19-related morbidity during the first and second epidemic wave in 2020 and compared these to the general Dutch paediatric population. Methods: We collected residual plasma samples from all paediatric patients (1 month-17 years of age) visiting our clinic or emergency room, who had blood drawing for various medical reasons. Samples were analysed for the presence of total antibodies against SARS-CoV-2 by Wantai ELISA. The seroprevalence in two separate periods (July-Sep 2020, and Oct-Dec 2020) was compared to regional and national data (PIENTER-Corona study, September 2020), and associations with co-morbidities were assessed. Results: A total of 209 samples in period 1 and 240 samples in period 2 were collected (median age 7.1 years, IQR 1.5-13.5). SARS-CoV-2 antibodies were detected in 4.1% and 13.8%, respectively (p< 0.001). Seroprevalence was higher compared to national paediatric data, but did not differ with regional estimates. Most children with SARS-CoV-2 antibodies were seen in the outpatient clinic for general paediatric problems with no differences in medical reasons for presentation between the two periods. Conclusions: These data confirm a rapid three-fold increase in SARS-CoV-2 seroprevalence in paediatric patients in the second half of 2020 with a trend towards a higher seroprevalence compared to randomly-selected children in a nationwide study. Underlying morbidity in children might not play an important role in acquiring SARS-CoV-2 infection.

Comparison of diagnostic accuracies of rapid serological tests and ELISA to molecular diagnostics in patients with suspected coronavirus disease 2019 presenting to the hospital.

OBJECTIVES: To assess the diagnostic performance of rapid lateral flow immunochromatographic assays (LFAs) compared with an ELISA and nucleic acid amplification tests (NATs) in individuals with suspected coronavirus disease 2019 (COVID-19). METHODS: Patients presenting to a Dutch teaching hospital were eligible between 17 March and 10 April 2020, when they had respiratory symptoms that were suspected for COVID-19. The performances of six different LFAs were evaluated in plasma samples obtained on corresponding respiratory sample dates of NATs testing. Subsequently, the best performing LFA was evaluated in 228 patients and in 50 sera of a historical patient control group. RESULTS: In the pilot analysis, sensitivity characteristics of LFA were heterogeneous, ranging from 2/20 (10%; 95% CI 0%-23%) to 11/20 (55%; 95% CI 33%-77%). In the total cohort, Orient Gene Biotech COVID-19 IgG/IgM Rapid Test LFA had a sensitivity of 43/99 (43%; 95% CI 34%-53%) and specificity of 126/129 (98%; 95% CI 95%-100%). Sensitivity increased to 31/52 (60%; 95% CI 46%-73%) in patients with at least 7 days of symptoms, and to 21/33 (64%; 95% CI 47%-80%) in patients with C-reactive protein (CRP) ≥100 mg/L. Sensitivity and specificity of Wantai SARS-CoV-2 Ab ELISA was 59/95 (62%; 95% CI 52%-72%) and 125/128 (98%; 95% CI 95%-100%) in all patients, respectively, but sensitivity increased to 38/48 (79%; 95% CI 68%-91%) in patients with at least 7 days of symptoms. CONCLUSIONS: There is large variability in diagnostic test performance between rapid LFAs, but overall limited sensitivity and high specificity in acutely admitted patients. Sensitivity improved in patients with longer existing symptoms or high CRP. LFAs should only be considered as additional triage tools when these may lead to the improvement of hospital logistics.

Smartphones as mobile microbiological laboratories.

BACKGROUND: Point-of-care (POC) tests provide an alternative to traditional laboratory-based diagnostics due to reduced turnaround times, portability and no need for highly trained laboratory staff. Smartphones can be integrated into POC platforms because of their multifunctionality, enabled by high-quality digital cameras, computer processors, touchscreen interface and wireless data transfer. It is predicted that by 2020 about 80% of the world population will use smartphones. OBJECTIVES: This review summarizes the current state of the art regarding smartphones as part of a mobile microbiological laboratory. SOURCES: Selected peer-reviewed publications on smartphone-based microbiological testing published between January 2015 and August 2019. CONTENT: Smartphones can be used as instrumental interfaces, dongles, microscopes or test result readers (brightfield, colorimetric and fluorescent measurements), or combined with amplification methods such as loop-mediated isothermal amplification (LAMP) tests in portable POC test platforms. Smartphone-based tests offer opportunities for microbiological diagnostics in remote areas and both resource-limited and resource-rich settings. Wireless connectivity may facilitate epidemiological studies and creation of spatiotemporal disease prevalence maps. However, the current analytical performance of many smartphone-based POC tests must be improved and carefully validated in clinical settings by comparison with current diagnostic standards. IMPLICATIONS: Recent developments in smartphone-based POC tests for infectious diseases are promising, as evidenced by results from many proof-of-concept studies. Further progress will foster large-scale implementation of smartphone-based POC as mobile microbiological laboratories in the near future.

How scientists and physicians use Twitter during a medical congress.

OBJECTIVES: During medical congresses Twitter allows discussions to disseminate beyond the congress hall and reach a wider audience. Insights into the dynamics of social media interactions during congresses, dissemination of scientific information and the determinants of a successful tweet may allow us to better understand social media's role in science communication. METHODS: We retrospectively extracted social media data during the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) 2017 and 2018 using NodeXL. We compared social media activity during these two congresses. Subsequently, we conducted in-depth analyses to identify the components of a successful tweet and multivariable analysis to assess independent factors associated with retweet activity. RESULTS: In 2018, approximately 13 000 delegates attended ECCMID, but only 591 Twitter accounts actively tweeted about the congress. Although fewer tweets were posted in 2018 compared with 2017 (4213 versus 4657, respectively), ECCMID 2018 generated a 63% increase in the total number of retweets (p < 0.001). According to multivariable logistic regression analysis, using multimedia, URL or hashtags and mentioning other Twitter account(s) were independently associated with retweet success. Mentioning of other users and use of multimedia were the only consistent predictors of retweets irrespective of the number of followers. CONCLUSIONS: A substantial increase in retweet activity and a modest increase in the number of influential Twitter accounts were observed between two successive congresses. Dissemination of scientific messages is more successful when connected accounts are actively involved in social media activity, and social media posts constitute the right combination of components.

Identification and validation of distinct biological phenotypes in patients with acute respiratory distress syndrome by cluster analysis.

RATIONALE: We hypothesised that patients with acute respiratory distress syndrome (ARDS) can be clustered based on concentrations of plasma biomarkers and that the thereby identified biological phenotypes are associated with mortality. METHODS: Consecutive patients with ARDS were included in this prospective observational cohort study. Cluster analysis of 20 biomarkers of inflammation, coagulation and endothelial activation provided the phenotypes in a training cohort, not taking any outcome data into account. Logistic regression with backward selection was used to select the most predictive biomarkers, and these predicted phenotypes were validated in a separate cohort. Multivariable logistic regression was used to quantify the independent association with mortality. RESULTS: Two phenotypes were identified in 454 patients, which we named 'uninflamed' (N=218) and 'reactive' (N=236). A selection of four biomarkers (interleukin-6, interferon gamma, angiopoietin 1/2 and plasminogen activator inhibitor-1) could be used to accurately predict the phenotype in the training cohort (area under the receiver operating characteristics curve: 0.98, 95% CI 0.97 to 0.99). Mortality rates were 15.6% and 36.4% (p<0.001) in the training cohort and 13.6% and 37.5% (p<0.001) in the validation cohort (N=207). The 'reactive phenotype' was independent from confounders associated with intensive care unit mortality (training cohort: OR 1.13, 95% CI 1.04 to 1.23; validation cohort: OR 1.18, 95% CI 1.06 to 1.31). CONCLUSIONS: Patients with ARDS can be clustered into two biological phenotypes, with different mortality rates. Four biomarkers can be used to predict the phenotype with high accuracy. The phenotypes were very similar to those found in cohorts derived from randomised controlled trials, and these results may improve patient selection for future clinical trials targeting host response in patients with ARDS.

Personal life and working conditions of trainees and young specialists in clinical microbiology and infectious diseases in Europe: a questionnaire survey.

The purpose of this investigation was to assess the balance between the personal and professional lives of trainees and young European specialists in clinical microbiology (CM) and infectious diseases (ID), and determine differences according to gender, country of training, workplace and specialty. The Steering Committee of the Trainee Association of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) devised a questionnaire survey consisting, beyond the demographic questions, of nine yes/no questions, 11 Likert scale self-evaluations and one open-response item on parenthood, working conditions, quality of life, alcohol consumption and burnout. This anonymous survey in English was held between April and July 2015 among European CM/ID trainees and young specialists (<3 years after training completion). Responses from 416 participants with a mean age of 32 years [standard deviation (SD) 5 years] were analysed. Females and physicians from Northern/Western Europe (NWE) benefit more from paternity/maternity leaves even during training than their counterparts. Among all respondents, only half of breastfeeding mothers enjoyed the benefit of working hours flexibility. Only two-thirds of respondents found their working environment stimulating. In comparison to colleagues from other parts of Europe, trainees and young specialists from Southern/Eastern Europe (SEE) had less frequent regular meetings with mentors/supervisors and head of departments where trainees' issues are discussed. Also, physicians from SEE were more frequently victims of workplace mobbing/bullying in comparison to those from other regions. Finally, multivariate analysis showed that female gender, SEE region and ID specialty were associated with burnout feelings. Female gender and country of work from SEE largely determine satisfactory working conditions, the possibility of parenthood leaves, amount of leisure time, mobbing experiences and burnout feelings among European CM/ID trainees and young specialists.

Staphylococcus aureus colonization at ICU admission as a risk factor for developing S. aureus ICU pneumonia.

OBJECTIVE: To quantify the incidence of intensive care unit (ICU)-acquired pneumonia caused by Staphylococcus aureus (S. aureus) and its association with S. aureus colonization at ICU admission. METHODS: This was a post-hoc analysis of two cohort studies in critically ill patients. The primary outcome was the incidence of microbiologically confirmed S. aureus ICU-acquired pneumonia. Incidences of S. aureus ICU pneumonia and associations with S. aureus colonization at ICU admission were determined using competing risks analyses. In all ICUs, patients were screened for respiratory tract S. aureus carriage on admission as part of infection control policies. Pooling of data was not deemed possible because of heterogeneity in baseline differences in patient population. RESULTS: The two cohort studies contained data of 9156 ICU patients. The average carriage rate of S. aureus among screened patients was 12.7%. In total, 1185 (12.9%) patients developed ICU pneumonia. Incidences of S. aureus ICU pneumonia were 1.33% and 1.08% in cohorts 1 and 2, respectively. After accounting for competing events, the adjusted subdistribution hazard ratio (SHR) of S. aureus colonization at admission for developing S. aureus ICU pneumonia was 9.55 (95% CI 5.31-17.18) in cohort 1 and 14.54 (95% CI 7.24-29.21) in cohort 2. CONCLUSION: The overall cumulative incidence of S. aureus ICU pneumonia in these ICUs was low. Patients colonized with S. aureus at ICU admission had an up to 15 times increased risk for developing this outcome compared with non-colonized patients.

A large survey among European trainees in clinical microbiology and infectious disease on training systems and training adequacy: identifying the gaps and suggesting improvements.

The purpose of this investigation was to perform a survey among European clinical microbiology (CM) and infectious disease (ID) trainees on training satisfaction, training tools, and competency assessment. An online, anonymous survey in the English language was carried out between April and July 2015. There were 25 questions: seven in a 5-point Likert scale (1: worst scenario, 5: best scenario) and the remainder as closed multiple-choice questions in five areas (satisfaction, adequacy, system, mentorship, and evaluation of training). Included were 419 respondents (215 CM, 159 ID, and 45 combined CM/ID) from 31 European countries [mean age (standard deviation) 32.4 (5.3) years, 65.9 % women]. Regarding satisfaction on the training scheme, CM and ID scored 3.6 (0.9) and 3.2 (1.0), respectively. These scores varied between countries, ranging from 2.5 (1.0) for Italian ID to 4.3 (0.8) for Danish CM trainees. The majority of respondents considered training in management and health economics inadequate and e-learning and continuing medical education programs insufficient. Many trainees (65.3 % of CM and 62.9 % of ID) would like to have more opportunities to spend a part of their training abroad and expected their mentor to be more involved in helping with future career plans (63.5 % of CM and 53.4 % of ID) and practical skills (53.0 % of CM and 61.2 % of ID). Two-thirds of the respondents across the specialties agreed that a European exam should be developed, but half of them thought it should not be made mandatory. This survey shows high heterogeneity in training conditions in European countries, identifies perceived gaps in training, and suggests areas for improvements.

Respiratory syncytial virus in critically ill adult patients with community-acquired respiratory failure: a prospective observational study.

The incidence of respiratory syncytial virus (RSV) and influenza virus infection was determined during three RSV seasons in 158 adult patients consecutively admitted to the intensive care unit with community-acquired respiratory failure. Nasopharyngeal swabs were tested for the presence of RSV and influenza virus by real-time polymerase chain reaction. Six patients (4%) were positive for RSV and all recovered. This finding was in sharp contrast to influenza (23 (15%) patients, 4 (17%) deaths). In conclusion, even in the midst of the RSV season, RSV is an infrequent cause of respiratory failure in adults admitted to the intensive care unit.