Airborne Contamination
Recently Published Documents





Danúbia da Cunha De Sá-Caputo ◽  
Ana Carolina Coelho-Oliveira ◽  
Anelise Sonza ◽  
Laisa Liane Paineiras-Domingos ◽  
Redha Taiar ◽  

Background: The facemasks use has been discussed to prevent respiratory disease due airborne contamination. The aim of this study was to perform a systematic review about the face masks use to avoid airborne contamination during COVID-19 pandemic and related conditions, registered (PROSPERO-CRD42020198347) and performed according PRISMA. Methods: PubMed, Embase and Scopus databases were used to collect data. Observational studies, published in 2020, and English language, were included. Two reviewers independently identified records through database search and reference screening and disagreements were resolved by a third reviewer. Six studies were included. Results: The works investigated about the use of masks (different types) to prevent droplets dissemination with virus or bacterial suspension and decrease COVID-19 transmission routes, comfort, or temperature. The studies have moderate to critical risk of bias and the level of evidence is III-2. Conclusion: It is recommended facemask use to prevent droplets from escaping airborne and infecting other people, although there are different percentages of protection and can be possible a discomfort related the use. Further clinical trials to the effectiveness of face mask to avoid airborne contamination during the COVID-19 pandemic and the factors interfering with their effectiveness should be conducted.

2021 ◽  
Vol 3 (3) ◽  
pp. 102-105
Vinay S Dua ◽  
Amandeep Kaur ◽  
Ankit Sikri ◽  
Mitasha Sachdeva

A new coronavirus (Sars-CoV-2) was detected in China at the end of 2019 and has since caused a worldwide pandemic. This virus is responsible for an acute respiratory syndrome (COVID-19), distinguished by a potentially lethal interstitial bilateral pneumonia. As Sars-CoV-2 is highly infective through airborne contamination, the high infection risk in the dental environment is a serious problem for both professional practitioners and patients. This literature overview at analyzing various reports available on oral symptoms along with possible causation, their relationship to the time of occurrence of clinical symptoms of this global pandemic.

Gavin P. Horn ◽  
Daniel Madrzykowski ◽  
Danielle L. Neumann ◽  
Alexander C. Mayer ◽  
Kenneth W. Fent

Birgitta Lytsy ◽  
Anna Hambraeus ◽  
Bengt Ljungqvist ◽  
Ulrika Ransjö ◽  
Berit Reinmüller

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 450
Ana Monteiro ◽  
Beatriz Almeida ◽  
Inês Paciência ◽  
João Cavaleiro Rufo ◽  
Edna Ribeiro ◽  

This study aims to assess the airborne bioburden of rural and urban Portuguese Primary Health Care Centers (PHCC) using active and passive sampling methods and identify the potential differences in airborne microbiota between both environments. The highest total aerobic mesophilic bacterial load in indoor air were found in the Vaccination Room (448 CFU.m−3) in the Rural PHCC and in the Waiting Room (420 CFU.m−3) for Urban PHCC. The total coliforms contamination level in indoor air was detected only in the Cleaning Supplies Room (4 CFU.m−3) in the Urban PHCC. The most frequent bacteria genera identified was Micrococcus (21% Rural PHCC; 31% Urban PHCC). The surface samples showed a highest total aerobic mesophilic bacterial contamination in the Treatment Room (86 × 103 CFU.m−2) from the Rural PHCC and in the Front Office (200 × 103 CFU.m−2) from the Urban PHCC. The electrostatic dust cloth (EDC) samples showed a highest bacterial load in the Urban PHCC. Total aerobic mesophilic bacterial load in settled dust and in the Heating, Ventilating and Air Conditioning (HVAC) filter samples in the Urban PHCC (8 CFU.g−1 and 6 × 103 CFU.m−2) presented higher values compared with the Rural PHCC (1 CFU.g−1 and 2.5 × 103 CFU.m−2). Urban PHCC presented higher bacterial airborne contamination compared with the Rural PHCC for the majority of sampling sites, and when compared with the indoor air quality (IAQ) Portuguese legislation it was the Rural PHCC in two sampling places who did not comply with the established criteria.

Thomas Scheier ◽  
Cyril Shah ◽  
Michael Huber ◽  
Hugo Sax ◽  
Barbara Hasse ◽  

AbstractThe rapid spread of the coronavirus disease 2019 pandemic urged immense testing capacities as one cornerstone of infection control. Many institutions opened outpatient SARS-CoV-2 test centers to allow large number of tests in comparatively short time frames. With increasing positive test rates, concerns for a possible airborne or droplet contamination of specimens leading to false-positive results were raised. In our experimental series performed in a dedicated SARS-CoV-2 test center, 40 open collection tubes placed for defined time periods in proximity to individuals were found to be SARS-CoV-2 negative. These findings argue against false-positive SARS-CoV-2 results due to droplet or airborne contamination.

2021 ◽  
Martin Ferrand ◽  
Mathieu Guingo ◽  
Christian Beauchêne ◽  
Maurice Mimoun ◽  
Jean-Pierre Minier

<p>Faced with the first Covid-19 epidemic wave in France, the hospital sector has been forced to considerably increase the number of intensive care beds. To meet this crucial need, some hospital structures have been adapted. This is the case with one of the intensive care sectors of the Burn Treatment Center (CTB) at Saint-Louis Hospital, which has intensive care rooms dedicated to treat burn patients. Beyond the provision and adaptation of these care structures to Covid patients, the hospital has currently an imperative need to progress on the understanding of the dispersion of buccopharyngeal droplets which constitute one of the risk vectors of airborne transmission and as a corollary of manual transmission.</p><p>As part of a partnership between CTB and the EDF Foundation, a CEREA research team provided the hospital with its aeraulics expertise which mainly relies on the digital modelling tool (CFD) code_saturne developed for more than 20 years by EDF-Research and Development. Numerical modelling in fluid mechanics makes it possible to accurately reproduce an architectural ensemble, to describe the air flows and what they carry, and thus to better understand where the risks of airborne contamination lie.</p><p>The objective of the study is to understand the dispersion of the buccopharyngeal droplets in the resuscitation room according to their sizes, identify the areas at risk of deposit, adapt the treatment protocols and optimise the level and the frequency of systematic bio-cleaning of surfaces exposed to deposit of oral-pharyngeal droplets. It should be noted that we are not directly dealing with the spread of the covid-19 virus but with one of the potential vehicles of oral-pharyngeal droplets.</p><p>The methodology consist of a parametric study of poly-dispersion of classes of particles. Each class correspond to a droplet diameter and contains one million of independent droplets for which a Generalized Langevin Model is solved to calculate the instantaneous fluid velocity seen from the particle, the particle velocity and its position. These particles are carried by a turbulent flow using the Reynolds Averaged Navier-Stokes approach, calculating only moments. The specific characteristics of this model allow dealing with poly-dispersed two-phase flow even for particles with very small diameters. The studied parameters are the angle of droplet ejection, the volume of humid air ejected and the time duration of this event and the air flowing activation of the room.</p><p>Expected conclusions are found: the largest particles sediment the fastest and close to the source, the finest droplets follow the streamlines to the air vents. In addition, non-intuitive areas of potential deposit are observed and a major impact of air conditioning on residence time is demonstrated.</p><p><img src="" alt=""></p>

2021 ◽  
Alicia Mateos-Cárdenas ◽  
Patricio Peñalver-Duque ◽  
David León-Muez

<p>Plastic pollution research and awareness activities have increased exponentially over the last decade, however not all citizen science activities are run with a degree of control assurance. Also, not many research projects include collaborations beyond academia or have set goals for the dissemination of results to specific non-academic stakeholders. Here, our project involves a range of collaborators from different disciplines, from the Irish academic sector to Spanish environmental NGOs and citizen scientists. Also, the project is funded by the US-based NGO Sustainable Ocean Alliance (SOA). We selected the natural area of Maro-Cerro Gordo Cliffs (southern Spain) as our sampling site due of its special status under Natura 2000. Despite this protection, previous monitoring work in 2019 identified heavily plastic polluted sites due to intensive agriculture activities in the area. Therefore, this project was designed as a citizen science initiative with a focus on (1) clean up and characterisation of litter from selected terrestrial and aquatic sites, both freshwater and coastal, and (2) an analysis of microplastics in stream and coastal waters. The main objectives of the project are to characterise the presence of litter and microplastics while working closely with citizen scientists, raising awareness and informing local authorities about the issue.</p><p> </p><p>First sampling activities were carried out in December 2020. A second field trip is organised for February 2021. Citizen scientists were previously trained and always worked together under the supervision of a team member. Litter was collected following transects and using tracking apps (eLitter and MARNOBA). A total of 43 items were collected from stream transects whereas 59 items were collected in beach transects. Remarkably, 74% of litter collected in streams were plastic items, 12% were other materials, 9% was paper or cardboard and 5% was metal. Whereas in beach transects, 51% of the litter collected was paper or cardboard, 25% plastic, 10% metal and 14% other materials. Regarding microplastic sampling, 200 L of stream water and 50000 L of coastal water samples were collected using a filtration unit with a 45 µm pore size. The volume of filtered coastal water was significantly higher as it was collected from three kayaks for 30 minutes. Microfibres and fragments have been detected at both sites. Sample processing and polymer analysis is currently ongoing using FTIR. All protocols follow strict QA/QC guidelines including clean conditions and airborne contamination procedures.</p><p> </p><p>Results from this project will be submitted for peer-review and also shared in the form of mid-term and final reports among local stakeholders including local environmental managers and SOA. Also, citizen scientists will take part of a workshop aimed at informing the general public. Therefore, the findings from this project are directly used to raise awareness through citizen scientists and informing local and international non-profit stakeholders. More specifically, lessons learned will be presented at EGU in the form of successes and challenges for discussion. It is imperative that, when feasible, high quality environmental research is carried out between cross-disciplinary collaborators in order to gather sound data while raising awareness and discussing solutions.</p>

2021 ◽  
Vol 15 (1) ◽  
pp. 1-3
Vittorio Checchi ◽  
Sara Ragazzini ◽  
Nicola Ragazzini

Background: At the beginning of 2020, a new pathogen named SARS-CoV-2 spread from China to the globe, becoming responsible for a potentially lethal acute respiratory syndrome: COVID-19. Direct contact and airborne contamination are the most frequent infection ways of SARS-CoV-2. During routine dental practice, SARS-CoV-2 transmission can occur through direct contact with mucous membranes, oral fluids, and contaminated instruments or inhalation of aerosol from infected patients. Introduction: Tooth extraction often involves exposure to blood and oral fluids, and the use of a rubber dam could be indicated to minimize direct contact and to decrease the amount of potentially infected droplets around the operatory field. The aim of this clinical case is to show how the use of a rubber dam could help in preventing or minimizing COVID-19 exposure during dental extraction. Materials and Methods: A 32-year-old patient reported severe pain and discomfort to an upper first molar due to a deep carious lesion and vertical tooth fracture. Under local anaesthesia, a rubber dam was placed, isolating the whole upper right sextant, and an atraumatic extraction was performed. Results: All three roots were intact, the bone septum was stable, and no oro-antral communication was present. A gauze swab was placed onto the socket and compressed slightly. After 5 minutes, the socket stopped bleeding, and both clamp and rubber dam, were removed. Conclusion: Within the limits of this single case report, the use rubber dam prior to tooth extraction could be a useful device to decrease aerosol spread and exposure to blood.

2021 ◽  
Vol Publish Ahead of Print ◽  
Robert H. Osher ◽  
Gabriel B Figueiredo ◽  
Julia G. Schneider ◽  
Jens Kratholm

Sign in / Sign up

Export Citation Format

Share Document