Concordance of SARS-CoV-2 RNA in Aerosols From a Nurses Station and in Nurses and Patients During a Hospital Ward Outbreak

Characterizing presenteeism among healthcare personnel at an academic medical center across eras of the COVID-19 pandemic

OBJECTIVE

To assess the frequency of and motivations for acute respiratory illness (ARI) presenteeism in healthcare personnel (HCP) during two waves of COVID-19.

DESIGN

Survey.

SETTING

Large academic medical center, both ambulatory and acute care settings.

PARTICIPANTS

All HCPs (n = 11,429) at the University of North Carolina Medical Center were eligible for two voluntary, electronic surveys: pre-Omicron (n = 591, recall period March 2020 - December 2021) and Omicron BA.1 (n = 385, recall period January - April 2022).

METHODS

We compared self-reported ARI presenteeism (working despite feeling feverish plus cough and/or sore throat) and motivators across time and demographics. We also estimated effects of workplace perceptions and culture on ARI presenteeism with log-binomial regression, adjusting for age, gender, HCP role, and patient interaction.

RESULTS

In the pre-Omicron and Omicron BA.1 eras, 24% and 34% of respondents respectively reported at least one instance of ARI presenteeism. In both eras, clinical frontline HCP were more likely to report ARI presenteeism than other roles, as were HCP primarily providing direct patient care vs not. Pre-Omicron motivators included disciplinary action and sick leave concerns, whereas workplace culture predominated during Omicron. Feeling professional obligation to attend work and observing colleague presenteeism increased ARI presenteeism in both eras. During Omicron, COVID-19 burnout, fatigue, and unclear call-out procedures increased ARI presenteeism.

CONCLUSIONS

ARI presenteeism was common and had diverse motivations, including workplace culture, disciplinary action, and sick leave. Efforts to reduce presenteeism should address these factors and prioritize frontline clinical personnel with direct patient interaction.

Detection of active SARS-CoV-2 in cough aerosols from COVID-19 patients

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an airborne pathogen, but detection of infectious SARS-CoV-2 in air and in particular the introduction of the virus into the environment by different human expiratory manoeuvres is not well studied.

OBJECTIVES

The aim of this study was to investigate the presence of SARS-CoV-2 in cough from coronavirus disease of 2019 (COVID-19) in-patients and to study contamination of the virus in the patient's environment.

METHODS

Detection of SARS-CoV-2 in cough was analyzed by PCR, culture and imaging. Detection in cough was compared to presence of the virus in air and on surfaces from patient rooms.

RESULTS

Twenty-five patients in 21 rooms were included in the study. SARS-CoV-2 RNA was found in cough aerosols from 16 out of 22 patients that produced voluntary cough. As demonstrated by plaque-forming unit assays, active virus was isolated from 11 of these 16 patients. Using mainly molecular detection, the virus was also found in air, on high-contact surfaces, and no-touch surfaces from the room of the COVID-19 patients.

CONCLUSIONS

These results show that infectious SARS-CoV-2 circulating in air can originate from patient cough and should be considered against the risk of acquiring COVID-19 through inhalation.

Evidence from whole genome sequencing of aerosol transmission of SARS-CoV-2 almost 5 hours after hospital room turnover

Experimental evidence suggests that Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) remains viable within aerosols with a half-life of approximately 3 hours; however, it remains unclear how long airborne SARS-CoV-2 can transmit infection. Whole genome sequencing during an outbreak suggested in-room transmission of SARS-CoV-2 to two patients admitted nearly 2 and 5 hours, respectively, after discharge of an asymptomatic infected patient. These findings suggest that airborne SARS-CoV-2 may transmit infection for over 4 hours, even in a hospital setting.

Advancements in Airborne Viral Nucleic Acid Detection with Wearable Devices

Wearable health sensors for an expanding range of physiological parameters have experienced rapid development in recent years and are poised to disrupt the way healthcare is tracked and administered. The monitoring of environmental contaminants with wearable technologies is an additional layer of personal and public healthcare and is also receiving increased focus. Wearable sensors that detect exposure to airborne viruses could alert wearers of viral exposure and prompt proactive testing and minimization of viral spread, benefitting their own health and decreasing community risk. With the high levels of asymptomatic spread of COVID-19 observed during the pandemic, such devices could dramatically enhance our pandemic response capabilities in the future. To facilitate advancements in this area, this review summarizes recent research on airborne viral detection using wearable sensing devices as well as technologies suitable for wearables. Since the low concentration of viral particles in the air poses significant challenges to detection, methods for airborne viral particle collection and viral sensing are discussed in detail. A special focus is placed on nucleic acid-based viral sensing mechanisms due to their enhanced ability to discriminate between viral subtypes. Important considerations for integrating airborne viral collection and sensing on a single wearable device are also discussed.

Air Change Rate and SARS-CoV-2 Exposure in Hospitals and Residences: A Meta-Analysis

As SARS-CoV-2 swept across the globe, increased ventilation and implementation of air cleaning were emphasized by the US CDC and WHO as important strategies to reduce the risk of inhalation exposure to the virus. To assess whether higher ventilation and air cleaning rates lead to lower exposure risk to SARS-CoV-2, 1274 manuscripts published between April 2020 and September 2022 were screened using key words "airborne SARS-CoV-2 or "SARS-CoV-2 aerosol". Ninety-three studies involved air sampling at locations with known sources (hospitals and residences) were selected and associated data were compiled. Two metrics were used to assess exposure risk: SARS-CoV-2 concentration and SARS-CoV-2 detection rate in air samples. Locations were categorized by type (hospital or residence) and proximity to the sampling location housing the isolated/quarantined patient (primary or secondary). The results showed that hospital wards had lower airborne virus concentrations than residential isolation rooms. A negative correlation was found between airborne virus concentrations in primary-occupancy areas and air changes per hour (ACH). In hospital settings, sample positivity rates were significantly reduced in secondary-occupancy areas compared to primary-occupancy areas, but they were similar across sampling locations in residential settings. ACH and sample positivity rates were negatively correlated, though the effect was diminished when ACH values exceeded 8. While limitations associated with diverse sampling protocols exist, data considered by this meta-analysis support the notion that higher ACH may reduce exposure risks to the virus in ambient air.

Designed for a pandemic: Mitigating the risk of SARS-CoV-2 transmission through hospital design and infrastructure

BACKGROUND

To describe the new Royal Adelaide Hospital (RAH) design and infrastructure features that helped mitigate the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission within the hospital during the pre-vaccination and pre-antiviral period.

METHOD

The RAH infrastructure, design and initial pandemic response was assessed. A retrospective review of all confirmed or suspected coronavirus disease 2019 (COVID-19) patients admitted from 1 February 2020 to 30 May 2020 was also performed to assess risk of transmission. Outbreak response reports were reviewed to identify episodes of nosocomial COVID-19.

RESULTS

Key infrastructure features include single-bed overnight rooms with dedicated bathrooms, creation of pandemic areas accessible only to pandemic staff, and sophisticated air-handling units with improved ventilation. A total of 264 COVID-19 related admission occurred, with 113 confirmed cases and 1579 total cumulative bed days. Despite a limited understanding of SARS-CoV-2 transmission, no vaccination or anti-viral therapy, global shortages of particulate filter respirators and restricted testing during this period, only one probable nosocomial COVID-19 case occurred in a healthcare worker, with no nosocomial cases involving patients.

CONCLUSIONS

The RAH design and pandemic features complimented existing infection control interventions and was important in limiting nosocomial spread of SARS-CoV-2.

Time trends and modifiable factors of COVID-19 contact tracing coverage, Geneva, Switzerland, June 2020 to February 2022

BackgroundContact tracing was one of the central non-pharmaceutical interventions implemented worldwide to control the spread of SARS-CoV-2, but its effectiveness depends on its ability to detect contacts.AimEvaluate the proportion of secondary infections captured by the contact tracing system in Geneva.MethodsWe analysed 166,892 concomitant infections occurring at the same given address from June 2020 until February 2022 using an extensive operational database of SARS-CoV-2 tests in Geneva. We used permutation to compare the total number of secondary infections occurring at the same address with that reported through manual contact tracing.ResultsContact tracing captured on average 41% of secondary infections, varying from 23% during epidemic peaks to 60% during low epidemic activity. People living in wealthy neighbourhoods were less likely to report contacts (odds ratio (OR): 1.6). People living in apartment buildings were also less likely to report contacts than those living in a house (OR: 1.1-3.1) depending on the SARS-CoV-2 variant, the building size and the presence of shops. This under-reporting of contacts in apartment buildings decreased during periods of mandatory wearing of face masks and restrictions on private gatherings.ConclusionContact tracing alone did not detect sufficient secondary infections to reduce the spread of SARS-CoV-2. Campaigns targeting specific populations, such as those in wealthy areas or apartment buildings, could enhance coverage. Additionally, measures like wearing face masks, improving ventilation and implementing restrictions on gatherings should also be considered to reduce infections resulting from interactions that may not be perceived as high risk.

Sickness presenteeism in healthcare workers during the coronavirus disease 2019 (COVID-19) pandemic: An observational cohort study

Sickness presenteeism among healthcare workers (HCW) risks nosocomial infection, but its prevalence among HCW with COVID-19 is unknown. Contemporaneous interviews revealed a sickness presenteeism prevalence of 49.8% among 255 HCW with symptomatic COVID-19. Presenteeism prevalence did not differ among HCW with and without specific COVID-19 symptoms or direct patient care.

Whole-genome sequencing to investigate transmission of SARS-CoV-2 in the acute healthcare setting: a systematic review

BACKGROUND

Whole-genome sequencing (WGS) has been used widely to elucidate transmission of SARS-CoV-2 in acute healthcare settings, and to guide infection, prevention, and control (IPC) responses.

AIM

To systematically appraise available literature, published between January 1st, 2020 and June 30th, 2022, describing the implementation of WGS in acute healthcare settings to characterize nosocomial SARS-CoV-2 transmission.

METHODS

Searches of the PubMed, Embase, Ovid MEDLINE, EBSCO MEDLINE, and Cochrane Library databases identified studies in English reporting the use of WGS to investigate SARS-CoV-2 transmission in acute healthcare environments. Publications involved data collected up to December 31st, 2021, and findings were reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

FINDINGS

In all, 3088 non-duplicate records were retrieved; 97 met inclusion criteria, involving 62 outbreak analyses and 35 genomic surveillance studies. No publications from low-income countries were identified. In 87/97 (90%), WGS supported hypotheses for nosocomial transmission, while in 46 out of 97 (47%) suspected transmission events were excluded. An IPC intervention was attributed to the use of WGS in 18 out of 97 (18%); however, only three (3%) studies reported turnaround times ≤7 days facilitating near real-time IPC action, and none reported an impact on the incidence of nosocomial COVID-19 attributable to WGS.

CONCLUSION

WGS can elucidate transmission of SARS-CoV-2 in acute healthcare settings to enhance epidemiological investigations. However, evidence was not identified to support sequencing as an intervention to reduce the incidence of SARS-CoV-2 in hospital or to alter the trajectory of active outbreaks.

Size distribution and relationship of airborne SARS-CoV-2 RNA to indoor aerosol in hospital ward environments

Aerosol particles proved to play a key role in airborne transmission of SARS-CoV-2 viruses. Therefore, their size-fractionated collection and analysis is invaluable. However, aerosol sampling in COVID departments is not straightforward, especially in the sub-500-nm size range. In this study, particle number concentrations were measured with high temporal resolution using an optical particle counter, and several 8 h daytime sample sets were collected simultaneously on gelatin filters with cascade impactors in two different hospital wards during both alpha and delta variants of concern periods. Due to the large number (152) of size-fractionated samples, SARS-CoV-2 RNA copies could be statistically analyzed over a wide range of aerosol particle diameters (70-10 µm). Our results revealed that SARS-CoV-2 RNA is most likely to exist in particles with 0.5-4 µm aerodynamic diameter, but also in ultrafine particles. Correlation analysis of particulate matter (PM) and RNA copies highlighted the importance of indoor medical activity. It was found that the daily maximum increment of PM mass concentration correlated the most with the number concentration of SARS-CoV-2 RNA in the corresponding size fractions. Our results suggest that particle resuspension from surrounding surfaces is an important source of SARS-CoV-2 RNA present in the air of hospital rooms.

Lessons learned from the COVID-19 pandemic-what Occupational Safety and Health can bring to Public Health

We strive to increase public (PH) and occupational health (OSH) inter-linkages by building a collaborative framework. Besides Covid-19 pandemic, recent approaches such as Human Exposome and Total Worker Health TM, have led to a shift to improving health of working population and consequently the total population. These health objectives can be best realised through primary care actors in specific contexts. Work, school, home and leisure are the four multi-stakeholder contexts in which health and healthcare (goal-oriented care) objectives needs to be set and defined. PH policy makers need to establish a shared decision-making process involving employees, employers and OSH representatives to set PH goals and align with OSH goals. The policy making process in OSH can serve as a potential way forward, as the decisions and policies are being decided centrally in consultation with social partners and governments. This process can then be mirrored on company level to adopt and implement.

Airborne transmission of SARS-Cov2: What consequences for digestive endoscopy?

The SARS-Cov-2 disease disrupted essential hospital procedures, such as gastrointestinal (GI) endoscopy, due to concerns about air transmission and the risk of exposing health care workers. With the spread of the pandemic, air transmission was considered as the main source of SARS-Cov2 transmission. This raised the problem of transmission by aerosolization of viral particles in operating rooms as well as endoscopy units. This is in line with the known airborne transmission of many other respiratory viruses. The risk of SARS-Cov-2 transmission during GI endoscopy was initially reduced by controlled measures, involving personal protections (mask…), restricted access to endoscopy rooms, and detection of infected patients. Gastrointestinal endoscopy generates aerosols, which may carry viruses. In addition, the endoscopy system may facilitate the diffusion of virus particles or fomites considering the forced-air cooling system used to maintain a stable temperature inside the box (25°C). The volume of air that goes through the light source box is high (240-300 m³ for a 1-h period). Moreover, the light system contains an air pump to inflate air inside the gut lumen. In order to isolate people from hazard, different levels of protection and solutions to avoid airborne transmission of microorganisms should be proposed, such as the reinforcement of personal protective equipment, the change in the way people work and engineering control of the risk.

Detection of hospital environmental contamination during SARS-CoV-2 Omicron predominance using a highly sensitive air sampling device

Background and objectives

The high transmissibility of SARS-CoV-2 has exposed weaknesses in our infection control and detection measures, particularly in healthcare settings. Aerial sampling has evolved from passive impact filters to active sampling using negative pressure to expose culture substrate for virus detection. We evaluated the effectiveness of an active air sampling device as a potential surveillance system in detecting hospital pathogens, for augmenting containment measures to prevent nosocomial transmission, using SARS-CoV-2 as a surrogate.

Methods

We conducted air sampling in a hospital environment using the AerosolSense^TM air sampling device and compared it with surface swabs for their capacity to detect SARS-CoV-2.

Results

When combined with RT-qPCR detection, we found the device provided consistent SARS-CoV-2 detection, compared to surface sampling, in as little as 2 h of sampling time. The device also showed that it can identify minute quantities of SARS-CoV-2 in designated "clean areas" and through a N95 mask, indicating good surveillance capacity and sensitivity of the device in hospital settings.

Conclusion

Active air sampling was shown to be a sensitive surveillance system in healthcare settings. Findings from this study can also be applied in an organism agnostic manner for surveillance in the hospital, improving our ability to contain and prevent nosocomial outbreaks.