Airborne contamination of COVID-19 in hospitals: a scoping review of the current evidence.

Introduction A controversy remains worldwide regarding the transmission routes of SARS-CoV-2 in hospital settings. We reviewed the current evidence on the air contamination with SARS-CoV-2 in hospital settings, and the factors associated to the contamination including the viral load and the particles size. Methods The MEDLINE, Embase, Web of Science databases were systematically interrogated for original English-language articles detailing COVID-19 air contamination in hospital settings between 1 December 2019 and 21 July 2020. This study was conducted in accordance with the PRISMA-ScR guidelines. The positivity rate of SARS-CoV-2 viral RNA and culture were described and compared according to the setting, clinical context, air ventilation system, and distance from patient. The SARS-CoV-2 RNA concentrations in copies per m3 of air were pooled and their distribution were described by hospital areas. Particle sizes and SARS-CoV-2 RNA concentrations in copies or TCID50 per m3 were analysed after categorization of sizes in <1 micrometers, 1-4 micrometers, and >4 micrometers. Results Among 2,034 records identified, 17 articles were included in the review. Overall, 27.5% (68/247) of air sampled from close patients environment were positive for SARS-CoV-2 RNA, without difference according to the setting (ICU: 27/97, 27.8%; non-ICU: 41/150, 27.3%; p=0.93), the distance from patients (<1 meter: 1/64, 1.5%; 1-5 meters: 4/67, 6%; p=0.4). In other areas, the positivity rate was 23.8% (5/21) in toilets, 9.5% (20/221) in clinical areas, 12.4% (15/121) in staff areas, and 34.1% (14/41) in public areas. A total of 78 viral cultures were performed in three studies, and 3 (4%) were positive, all from close patients environment. The median SARS-CoV-2 RNA concentrations varied from 1.103 copies per m3 (IQR: 0.4.103-9.103) in clinical areas to 9.7.103 (5.1.103-14.3.103) in the air of toilets or bathrooms. The protective equipment removal and patients rooms had high concentrations/titre of SARS-CoV-2 with aerosol size distributions that showed peaks in the <1 micrometers region, and staff offices in the >4 micrometers region. Conclusion In hospital, the air near and away from COVID-19 patients is frequently contaminated with SARS-CoV-2 RNA, with however, rare proofs of their viability. High viral loads found in toilet/bathrooms, staff and public hallways suggests to carefully consider these areas.

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Surgical Smoke and Airborne Microbial Contamination in Operating Theatres: Influence of Ventilation and Surgical Phases

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17155395 ◽

2020 ◽

Vol 17 (15) ◽

pp. 5395

Author(s):

Francesco Romano ◽

Samanta Milani ◽

Jan Gustén ◽

Cesare Maria Joppolo

Keyword(s):

Ultrafine Particles ◽

Microbial Contamination ◽

Ventilation System ◽

Contamination Level ◽

Operating Table ◽

Surgical Smoke ◽

Air Contamination ◽

Airborne Contamination ◽

Operating Theatres ◽

Ventilation Systems

Air cleanliness is a crucial factor in operating theatres (OTs), where the health of patients and staff must be preserved by controlling air contamination. Particular attention must be paid to ultrafine particles (UFPs) size range, generated for instance by electrosurgical instruments (ESTs). OT contamination is also affected by ventilation systems, medical staff and their gowning system, staff routines, instruments, etc. This comparative study is based on experimental measurements of airborne microbial contamination and UFPs carried out during real ongoing surgeries in two OTs equipped with upward displacement ventilation (UWD) and hybrid ventilation, with unidirectional airflow on the operating table and peripheral mixing (UDAF+Mixing) ventilation systems. Airborne contamination concentration at the exit grilles has been analyzed as function of four different surgical phases normally performed during an operation. Results highlight that airborne contamination is influenced by the activities carried out during the surgical phases. EST usage affects the contamination level more than staff size during operation observed. Colony forming unit (CFU) values in the protected area close to the patient’s wound are influenced more by the type of ventilation system than by surgical phases. CFU values decrease by 18 to 50 times from the UWD system to the hybrid one. The large airflow volumes supply together with high air velocities in OTs equipped with UDAF+Mixing systems guarantee a better and a safer airborne contamination control for patients and medical team in comparison with UWD systems.

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Comparison of two air sampling methods to monitor operating room air quality and assessment of air quality in two operating rooms with different ventilation systems in the national hospital of Sri Lanka

International Journal of Infection Control ◽

10.3396/ijic.v12i3.017.16 ◽

2016 ◽

Vol 12 (3) ◽

Cited By ~ 1

Author(s):

Tshokey Tshokey ◽

Pranitha Somaratne ◽

Suneth Agampodi

Keyword(s):

Air Quality ◽

Sri Lanka ◽

Operating Room ◽

Ventilation System ◽

Surgical Site Infections ◽

National Hospital ◽

Air Contamination ◽

Acceptable Method ◽

The Difference ◽

Laminar Air Flow

Air contamination in the operating room (OR) is an important contributor for surgical site infections. Air quality should be assessed during microbiological commissioning of new ORs and as required thereafter. Despite many modern methods of sampling air, developing countries mostly depended on conventional methods. This was studied in two ORs of the National Hospital of Sri Lanka (NHSL) with different ventilation system; a conventional ventilation (CV) and a laminar air flow (LAF). Both ORs were sampled simultaneously by two different methods, the settle plate and sampler when empty and during use for a defined time period. Laboratory work was done in the Medical Research Institute. The two methods of sampling showed moderate but highly significant correlation. The OR with CV was significantly more contaminated than LAF when empty as well as during use by both methods. Overall, the difference in contamination was more significant when sampled by the sampler. Differences in contamination in empty and in-use ORs were significant in both ORs, but significance is less in LAF rooms. The consistent and significant correlation between settle plate and sampler showed that the settle plate is an acceptable method. The LAF theatre showed less contamination while empty and during use as expected. Air contamination differences were more significant when sampled with sampler indicating that it is a more sensitive method. Both CV and LAF ORs of the NHSL did not meet the contamination standards for empty theatres but met the standards for in-use indicating that the theatre etiquette was acceptable.

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Indoor Air Quality Real-Time Monitoring in Airport Terminal Areas: An Opportunity for Sustainable Management of Micro-Climatic Parameters

Sensors ◽

10.3390/s18113798 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3798 ◽

Cited By ~ 9

Author(s):

Sara Zanni ◽

Francesco Lalli ◽

Eleonora Foschi ◽

Alessandra Bonoli ◽

Luca Mantecchini

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Real Time ◽

Indoor Air ◽

Electronic Monitoring ◽

Ventilation System ◽

Real Time Monitoring ◽

Airport Terminal ◽

Air Ventilation ◽

Gaseous Contaminants

Indoor air quality (IAQ) management in public spaces is assuming a remarkable importance. Busy environments, like airport terminals, are currently regarded as possible hotspots and IAQ is a crucial element for passengers and staff protection, as well as a key aspect of airport passenger experience. A one-month monitoring period has been performed on IAQ in the airport of Bologna (Italy), as prototypal example of large regional airport. Four strategic areas within the airport have been equipped with electronic monitoring platforms, including different contaminants and two microclimatic sensors. Data suggest that daily variation in IAQ parameters typically follow the activity pattern of the different environments under study (i.e., passengers’ flows) for gaseous contaminants, where particulate matter counts oscillate in a definite range, with a significant role played by ventilation system. Gaseous contaminants show a correlation between indoor and outdoor concentrations, mainly due to airside activities. Micro-climatic comfort parameters have been tested to match with standards for commercial environments. As results appears in line with typical households IAQ values, the current air ventilation system appears to be adequate. Nevertheless, an integrated air management system, based on real-time monitoring, would lead to optimization and improvement in environmental and economical sustainability.

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High concentrations of coarse particles emitted from a cattle feeding operation

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-8809-2011 ◽

2011 ◽

Vol 11 (16) ◽

pp. 8809-8823 ◽

Cited By ~ 22

Author(s):

N. Hiranuma ◽

S. D. Brooks ◽

J. Gramann ◽

B. W. Auvermann

Keyword(s):

United States ◽

Particulate Matter ◽

Chemical Properties ◽

Field Measurements ◽

The United States ◽

Water Soluble ◽

Size Distributions ◽

Cattle Feeding ◽

High Concentrations ◽

Organic Particles

Abstract. Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United States. In the summer of 2008, measurements and samplings were conducted at the upwind and downwind edges of the facility. A series of far-field measurements and samplings was also conducted 3.5 km north of the facility. Two instruments, a GRIMM Sequential Mobility Particle Sizer (SMPS) and a GRIMM Portable Aerosol Spectrometer (PAS), were used to measure particle size distributions over the range of 0.01 to 25 μm diameter. Raman microspectroscopy was used to determine the chemical composition of particles on a single particle basis. Volume size distributions of dust were dominated by coarse mode particles. Twenty-four hour averaged concentrations of PM10 (particulate matter with a diameter of 10 μm or less) were as high as 1200 μg m−3 during the campaign. The primary constituents of the particulate matter were carbonaceous materials, such as humic acid, water soluble organics, and less soluble fatty acids, including stearic acid and tristearin. A significant fraction of the organic particles was present in internal mixtures with salts. Basic characteristics such as size distribution and composition of agricultural aerosols were found to be different than the properties of those found in urban and semi-urban aerosols. Failing to account for such differences may lead to errors in estimates of aerosol effects on local air quality, visibility, and public health.

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The role of telehealth during COVID-19 outbreak: A systematic review based on current evidence

10.21203/rs.3.rs-23906/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Elham Monaghesh ◽

Alireza Hajizadeh

Keyword(s):

Systematic Review ◽

English Language ◽

Healthcare Providers ◽

Physical Contact ◽

Current Evidence ◽

Health Providers ◽

Search Results ◽

Effective Option ◽

Critical Appraisal Skills

Abstract Purpose The outbreak of coronavirus disease-19 (COVID-19) is a public health emergency of international concern. Telehealth is effective option to fight COVID-19 outbreak. The aim of this systematic review was to identify the role of telehealth services during COVID-19 outbreak.Methods This systematic review was conducted through searching five databases including PubMed, Scopus, Embase, Web of Science and Science direct. Inclusion criteria included studies clearly defined role of telehealth services in COVID-19 outbreak, published from December 31, 2019, written in English language and published in peer reviewed. Two reviewers independently assessed search results, extracted data, and assessed quality of included studies. Quality assessment was based on the Critical Appraisal Skills Program (CASP) checklist. Narrative synthesis was undertaken to summarize and report the findings.Results Eight studies met the inclusion out of the 142 search results. Currently, healthcare providers and patients who are self-isolating, telehealth is certainly appropriate to minimizing the risk of COVID-19 transmission. This solution has the potential to avoidance of direct physical contact, provide continuous care to the community and finally reduce morbidity and mortality in COVID-19 outbreak.Conclusions The use of telehealth improves the provision of health services. Therefore, telehealth should be an important tool in caring services while keeping patients and health providers safe as the COVID-19 outbreak.

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Assessing the efficacy of photocatalytic oxidation on bacterial contamination in a clinical setting – a randomised controlled trial

Journal of Infection Prevention ◽

10.1177/1757177411415447 ◽

2011 ◽

Vol 12 (6) ◽

pp. 251-253

Author(s):

Anwar Abbas Jafri ◽

Sanjay Gupta ◽

Zaki Ibrahim ◽

Paul Baker ◽

Tamsin Oswald ◽

...

Keyword(s):

Clinical Setting ◽

Photocatalytic Oxidation ◽

Controlled Trial ◽

Colony Count ◽

Clinical Environment ◽

Randomised Study ◽

Air Contamination ◽

Air Sampler ◽

Airborne Contamination ◽

Air Purifier

Airborne contamination has been shown to be a significant source of wound contamination in orthopaedic surgery. This is the first reported study looking at the efficacy of ActivTek 300, a portable UV/TiO2-based air purifier unit to reduce airborne contamination in a clinical setting. In this randomised study the investigator was blinded as to whether the unit had been on or off for the previous seven days. Air contamination was measured weekly using a validated technique in ward treatment rooms using a Mini Air Sampler (MAS-100) and agar plates, over a period of 12 weeks. The agar plates were then incubated for 24 hours and the results were expressed as number of colony forming units per plate (cfu). The biomedical scientist who manually counted the number of cfus was blinded as to whether the unit was on or off. Measurements were duplicated to improve the accuracy of the study, and in addition to this an identical experiment was set up in a second treatment room on a separate randomisation schedule. Analysis of the data demonstrated median colony count was significantly lower with the unit on (Median = 43 interquartile range (IQR) 30 to 83) than when it was off (median = 95 IQR 44 to 143) ( p < 0.01). This represents a 55% mean reduction in the colony count. This study suggests that the portable UV/TiO2-based air purifier unit is efficacious in reducing airborne contamination in the clinical environment and may have a promising role in reducing overall infection rates in surgical patients.

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Acoustical Improvements with Natural Air Ventilation in the Liu Institute for Global Issues at the University of British Columbia

Journal of Green Building ◽

10.3992/jgb.6.1.114 ◽

2011 ◽

Vol 6 (1) ◽

pp. 114-122

Author(s):

Zohreh Razavi ◽

Max Richter ◽

Murray Hodgson ◽

Alireza Khaleghi

Keyword(s):

Natural Ventilation ◽

Ventilation System ◽

Green Building ◽

Optimized Design ◽

Global Issues ◽

University Of British Columbia ◽

Air Ventilation ◽

The University ◽

Building Designs

Low speech privacy in shared and private offices in one of the early generation of a “green” building resulted in occupants' dissatisfaction. This problem is experienced in Liu institute with a natural-ventilation system. Such a system requires low air-flow resistance which is achieved by large openings which will result in noise transmission between various spaces within the building. The poor acoustical quality in this building resulted in occupants' noise complaints which were further investigated by way of relevant acoustical measurements. CATT-Acoustic software was utilized to modify the acoustical quality of the building without any disturbance to the occupants. The optimized design of the transfer box above the office door was selected based on CATT-Acoustic predictions. The acoustical measurements were conducted after installation of the transfer box above the office door. The measurements' results agreed with the predictions which led to improved speech privacy to an acceptable level between the office and the corridor in Liu Institute. More work should be done to improve the acoustical quality of natural-ventilated building to conform to ANSI standards.1The results of this study strongly support including acoustics in “green” building designs with natural ventilation to avoid users' complaints.

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Analysis of alternative ventilation strategies for existing multi-family buildings using CONTAM simulation software

E3S Web of Conferences ◽

10.1051/e3sconf/202017209004 ◽

2020 ◽

Vol 172 ◽

pp. 09004

Author(s):

Xinxiu Tian ◽

Jamie Fine ◽

Marianne Touchie

Keyword(s):

Ventilation System ◽

Poor Performance ◽

Simulation Software ◽

Base Case ◽

Building Model ◽

System A ◽

Airflow Distribution ◽

Air Ventilation ◽

Ventilation Strategies ◽

Post War

In many existing high-rise multi-family buildings, a pressurized corridor ventilation system is used to meet outdoor air ventilation requirements. However, this system often has poor performance, leading to under- or over- ventilation in different parts of a building. This study examines three ventilation strategies including: the base case, which is a traditional pressurized corridor ventilation system, a direct-to-suite ducted ventilation system, and a suite-based HRV ventilation system. A building model was constructed in CONTAM using features of a typical post-war multi-family building in Toronto, Canada. All three strategies were simulated using CONTAM under both summer and winter conditions. The resulting outdoor airflow delivery rates to the suites and corridor pressure differentials were compared to assess the effectiveness of each strategy. The results show that the suite-based HRV strategy is able to provide adequate ventilation airflow to individual suites in both summer and winter. In the traditional pressurized corridor system and the direct-to-suite ducting system, the airflows delivered to the suites located at the top of the building are higher than those delivered to the suites located at the bottom of the building. This uneven airflow distribution is more pronounced in winter when stack effect impacts the ventilation system more significantly.

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Patient satisfaction of telephone or video interpreter services compared with in-person services: a systematic review

Australian Health Review ◽

10.1071/ah16195 ◽

2018 ◽

Vol 42 (2) ◽

pp. 168 ◽

Cited By ~ 9

Author(s):

Corey Joseph ◽

Marie Garruba ◽

Angela Melder

Keyword(s):

Patient Satisfaction ◽

Consumer Satisfaction ◽

English Language ◽

Ad Hoc ◽

A Priori ◽

Current Evidence ◽

Cochrane Library ◽

Interpreter Services ◽

Interpreter Service ◽

Google Search

Objective This review was conducted to identify and synthesise the evidence around the use of telephone and video interpreter services compared with in-person services in healthcare. Methods A systematic search of articles published in the English language was conducted using PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Library, Database of Abstracts of Reviews of Effects (DARE), Joanna Briggs, Google Scholar and Google. Search terms included ‘interpreter’, ‘patient satisfaction’, ‘consumer satisfaction’ and ‘client satisfaction’. Any study that did not compare in-person interpreter services with either telephone or video interpreter services was excluded from analysis. Studies were screened for inclusion or exclusion by two reviewers, using criteria established a priori. Data were extracted via a custom form and synthesised. Results The database search yielded 196 studies, eight of which were included in the present review. The search using an Internet search engine did not identify any relevant studies. Of the studies included, five used telephone and three used video interpreter services. All studies, except one, compared levels of satisfaction regarding in-person interpretation and telephone or video interpretation. One study compared satisfaction of two versions of video interpretation. There is evidence of higher satisfaction with hospital-trained interpreters compared with ad hoc (friend or family) or telephone interpreters. There is no difference in satisfaction between in-person interpreting, telephone interpreting or interpretation provided by the treating bilingual physician. Video interpreting has the same satisfaction as in-person interpreting, regardless of whether the patient and the physician are in the same room. Higher levels of satisfaction were reported for trained telephone interpreters than for in-person interpreters or an external telephone interpreter service. Conclusions Current evidence does not suggest there is one particular mode of interpreting that is superior to all others. This review is limited in its translational capacity given that most studies were from the US and in a Spanish-speaking cohort. What is known about the topic? Access to interpreters has been shown to positively affect patients who are not proficient in speaking the local language of the health service. What does this paper add? This paper adds to the literature by providing a comprehensive summary of patient satisfaction when engaging several different types of language interpreting services used in healthcare. What are the implications for practitioners? This review provides clear information for health services on the use of language interpreter services and patient satisfaction. The current body of evidence does not indicate a superior interpreting method when patient satisfaction is concerned.

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Ice Microphysics Observations in Hurricane Humberto: Comparison with Non-Hurricane-Generated Ice Cloud Layers

Journal of the Atmospheric Sciences ◽

10.1175/jas3603.1 ◽

2006 ◽

Vol 63 (1) ◽

pp. 288-308 ◽

Cited By ~ 25

Author(s):

Andrew J. Heymsfield ◽

Aaron Bansemer ◽

Stephen L. Durden ◽

Robert L. Herman ◽

T. Paul Bui

Keyword(s):

Doppler Radar ◽

Deep Convection ◽

Particle Growth ◽

Dual Wavelength ◽

Size Distributions ◽

Temperature Growth ◽

Radar Observations ◽

Ice Cloud ◽

Ice Particles ◽

High Concentrations

Abstract Measurements are presented that were acquired from the National Aeronautics and Space Administration (NASA) DC-8 aircraft during an intensive 3-day study of Tropical Storm/Hurricane Humberto on 22, 23, and 24 September 2001. Particle size distributions, particle image information, vertical velocities, and single- and dual-wavelength Doppler radar observations were obtained during repeated sampling of the eyewall and outer eye regions. Eyewall sampling temperatures ranged from −22° to −57°C and peak updraft velocities from 4 to 15 m s−1. High concentrations of small ice particles, in the order 50 cm−3 and above, were observed within and around the updrafts. Aggregates, some larger than 7 mm, dominated the larger sizes. The slope of the fitted exponential size distributions λ was distinctly different close to the eye than outside of that region. Even at low temperatures, λ was characteristic of warm temperature growth (λ < 30 cm−1) close to the eye and characteristic of low temperature growth outside of it as well (λ > 100 cm−1). The two modes found for λ are shown to be consistent with observations from nonhurricane ice cloud layers formed through deep convection, but differ markedly from ice cloud layers generated in situ. It is shown that the median, mass-weighted, terminal velocities derived for the Humberto data and from the other datasets are primarily a function of λ. Microphysical measurements and dual wavelength radar observations are used together to infer and interpret particle growth processes. Rain in the lower portions of the eyewall extended up to the 6- or 7-km level. In the outer eye regions, aggregation progressed downward from between 8.5 and 11.9 km to the melting layer, with some graupel noted in rainbands. Homogeneous ice nucleation is implicated in the high concentrations of small ice particles observed in the vicinity of the updrafts.

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