Experience and evidence, even during this pandemic, suggest that health care workers rarely acquire infections during patient care when proper PPE is used and that most of their infections are acquired in the community where PPE is typically not worn.5 Thus, it becomes important to know if practice from occupational safety can be used in the community as a bridge to longer-lasting measures, such as vaccines. Could a simple and affordable face shield, if universally adopted, provide enough added protection when added to testing, contact tracing, and hand hygiene to reduce transmissibility below a critical threshold? [...]
University of Hong Kong study finds eyes are ‘important route’ for coronavirus, up to 100 times more infectious than Sars
Researchers from HKU’s school of public health reveal the coronavirus is up to 100 times more infectious through the eyes and airways than Sars. Study in The Lancet Respiratory Medicine says that explains ‘higher transmissibility’ of Covid-19, compared with the 2003 contagion.
The study reinforces advice to the public not to touch their eyes and to wash hands regularly to avoid infection, after the university researchers previously found the coronavirus could survive as long as seven days on stainless steel surfaces and plastic.
Antimicrobial surface coating kills coronavirus for 90 days: study
The paper by researchers at the University of Arizona (UA), which has not yet been peer-reviewed, found that the amount of virus on coated surfaces reduced by 90 percent in 10 minutes and by 99.9 percent in two hours.
Charles Gerba, a microbiologist at UA who was the study's senior author, told AFP the technology was "the next advancement in infection control."
"I think it's mostly important for high-use surfaces like subways and buses, because you could disinfect them but then the next people that come in there will recontaminate the surfaces," he said.
A 2019 paper by UA researchers found that coatings reduced hospital-acquired infections by 36 percent.
Controlling the Spread of Disease in Schools
Pandemic and seasonal infectious diseases such as influenza may have serious negative health and economic consequences. Certain non-pharmaceutical intervention strategies – including school closures – can be implemented rapidly as a first line of defense against spread. Such interventions attempt to reduce the effective number of contacts between individuals within a community; yet the efficacy of closing schools to reduce disease transmission is unclear, and closures certainly result in significant economic impacts for caregivers who must stay at home to care for their children. Using individual-based computer simulation models to trace contacts among schoolchildren within a stereotypical school setting, we show how alternative school-based disease interventions have great potential to be as effective as traditional school closures without the corresponding loss of workforce and economic impacts. Benjamin J. Ridenhour, Alexis Braun, Thomas Teyrasse, David Goldsman
Ultrafine particle removal and generation by portable air cleaners
Portable air cleaners can both remove and generate pollutants indoors. To investigate these phenomena, we conducted a two-phase investigation in a 14.75 m3 stainless steel chamber. In the first phase, particle size-resolved (12.6–514 nm diameter) clean air delivery rates (CADR) and efficiencies were determined, as were ozone emission rates, for two high-efficiency particle arresting (HEPA) filters, one electrostatic precipitator with a fan, and two ion generators without fans. The two HEPA air cleaners had count average CADR (standard deviation) of 188 (30) and 324 (44) m3 h−1; the electrostatic precipitator 284 (62) m3 h−1; and the two ion generators 41 (11) and 35 (13) m3 h−1. The electrostatic precipitator emitted ozone at a rate of 3.8±0.2 mg h−1, and the two ion generators 3.3±0.2 and 4.3±0.2 mg h−1. Ozone initiates reactions with certain unsaturated organic compounds that produce ultrafine and fine particles, carbonyls, other oxidized products, and free radicals. During the second phase, five different ion generators were operated separately in the presence of a plug-in liquid or solid air freshener, representing a strong terpene source. For air exchange rates of between 0.49 and 0.96 h−1, three ion generators acted as steady-state net particle generators in the entire measured range of 4.61–157 nm, and two generated particles in the range of approximately 10 to 39–55 nm. Terpene and aldehyde concentrations were also sampled for one ion generator, and concentrations of terpenes decreased and formaldehyde increased. Given these results, the pollutant removal benefits of ozone-generating air cleaners may be outweighed by the generation of indoor pollution. Michael S. Waring, Jeffrey A. Siegel , Richard L. Corsi
Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period
It is urgent to understand the future of severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) transmission. We used estimates of seasonality, immunity, and cross-immunity for betacoronaviruses OC43 and HKU1 from time series data from the USA to inform a model of SARS-CoV-2 transmission. We projected that recurrent wintertime outbreaks of SARS-CoV-2 will probably occur after the initial, most severe pandemic wave. Absent other interventions, a key metric for the success of social distancing is whether critical care capacities are exceeded. To avoid this, prolonged or intermittent social distancing may be necessary into 2022. Additional interventions, including expanded critical care capacity and an effective therapeutic, would improve the success of intermittent distancing and hasten the acquisition of herd immunity. Longitudinal serological studies are urgently needed to determine the extent and duration of immunity to SARS-CoV-2. Even in the event of apparent elimination, SARS-CoV-2 surveillance should be maintained since a resurgence in contagion could be possible as late as 2024.
The effect of control strategies to reduce social mixing on outcomes of the COVID-19 epidemic in Wuhan, China: a modelling study
Background In December, 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus, emerged in Wuhan, China. Since then, the city of Wuhan has taken unprecedented measures in response to the outbreak, including extended school and workplace closures. We aimed to estimate the effects of physical distancing measures on the progression of the COVID-19 epidemic, hoping to provide some insights for the rest of the world.
Kiesha Prem*, Yang Liu*, Timothy W Russell, Adam J Kucharski, Rosalind M Eggo, Nicholas Davies, Centre for the Mathematical Modelling of Infectious Diseases COVID-19 Working Group†, Mark Jit, Petra Klepac
The Effect of Human Mobility and Control Measures on the COVID-19 Epidemic in China
The ongoing coronavirus disease 2019 (COVID-19) outbreak expanded rapidly throughout China. Major behavioral, clinical, and state interventions were undertaken to mitigate the epidemic and prevent the persistence of the virus in human populations in China and worldwide. It remains unclear how these unprecedented interventions, including travel restrictions, affected COVID-19 spread in China. We used real-time mobility data from Wuhan and detailed case data including travel history to elucidate the role of case importation in transmission in cities across China and to ascertain the impact of control measures. Early on, the spatial distribution of COVID-19 cases in China was explained well by human mobility data. After the implementation of control measures, this correlation dropped and growth rates became negative in most locations, although shifts in the demographics of reported cases were still indicative of local chains of transmission outside of Wuhan. This study shows that the drastic control measures implemented in China substantially mitigated the spread of COVID-19.
Recette friction hydro-alcoolique maison validée HUG
Trente secondes de friction hydroalcoolique équivalent à deux minutes de lavage des mains au savon. Dans le premier cas, on tue les germes, dans le second, on les décroche. J’ai créé un tableau où on peut entrer le volume de son flacon et obtenir automatiquement les proportions. Tout le monde a parlé de la recette OMS, moi le premier, sans vraiment expliquer comment on pouvait la mettre en œuvre chez soi, quand on ne dispose ni de béchers ni d’autres ustensiles de laboratoire. En relation avec les spécialistes des HUG, lieu d’invention des solutions hydroalcooliques modernes, je suis arrivé à une recette pratique qui ne nécessite qu’une balance électronique comme nous en utilisons en cuisine.
Recette friction hydro-alcoolique maison recommandé par L'OMS
Guide de Production locale : Formulations des Produits hydro-alcooliques recommandés par l’OMS. Ce guide de production locale des solutions hydro-alcooliques selon les formulations recommandées par l’OMS se compose de deux parties étroitement liées. La partie A est le guide de préparation des solutions recommandées destiné aux professionnels de la pharmacie. S’ils le souhaitent, les utilisateurs peuvent afficher ces consignes sur le lieu de production. La partie B est une synthèse des informations techniques essentielles, issues des Recommandations de l’OMS pour l’Hygiène des Mains au cours des Soins (2009). Ces données complémentaires concernent la sécurité et les coûts de production et de distribution.
Efficacy of Face Shields Against Cough Aerosol Droplets From a Cough Simulator
William G Lindsley et al. J Occup Environ Hyg. 2014.
Health care workers are exposed to potentially infectious airborne particles while providing routine care to coughing patients. However, much is not understood about the behavior of these aerosols and the risks they pose. We used a coughing patient simulator and a breathing worker simulator to investigate the exposure of health care workers to cough aerosol droplets, and to examine the efficacy of face shields in reducing this exposure. Our results showed that 0.9% of the initial burst of aerosol from a cough can be inhaled by a worker 46 cm (18 inches) from the patient. During testing of an influenza-laden cough aerosol with a volume median diameter (VMD) of 8.5 μm, wearing a face shield reduced the inhalational exposure of the worker by 96% in the period immediately after a cough. The face shield also reduced the surface contamination of a respirator by 97%. When a smaller cough aerosol was used (VMD = 3.4 μm), the face shield was less effective, blocking only 68% of the cough and 76% of the surface contamination. In the period from 1 to 30 minutes after a cough, during which the aerosol had dispersed throughout the room and larger particles had settled, the face shield reduced aerosol inhalation by only 23%. Increasing the distance between the patient and worker to 183 cm (72 inches) reduced the exposure to influenza that occurred immediately after a cough by 92%. Our results show that health care workers can inhale infectious airborne particles while treating a coughing patient. Face shields can substantially reduce the short-term exposure of health care workers to large infectious aerosol particles, but smaller particles can remain airborne longer and flow around the face shield more easily to be inhaled. Thus, face shields provide a useful adjunct to respiratory protection for workers caring for patients with respiratory infections. However, they cannot be used as a substitute for respiratory protection when it is needed. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: tables of the experiments performed, more detailed information about the aerosol measurement methods, photographs of the experimental setup, and summaries of the experimental data from the aerosol measurement devices, the qPCR analysis, and the VPA.].
Keywords: airborne particulate matter; health care workers; infectious disease transmission; protective devices; respiratory infections/prevention; universal precautions.
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visières imprimées par une imprimante 3D Visière de protection anti coronavirus Pour fabriquer des visières faciales imprimante 3D télécharger des plans sur la plate-forme visières de protection pour se protéger du coronavirus protection quasi-complète par leur effet anti projection au niveau des trois zones par lesquelles entre le virus : la bouche, le nez et le yeux" Docteur Sebastian Marciano, médecin généraliste aux Urgences médicales de Paris. Ils présentent aussi un intérêt pour les professionnels qui sont en deuxième ligne de l'épidémie comme les pompiers, les policiers ou les hôtesses de caisses. Composées d'écrans transparents en plexiglas, ces visières protègent des gouttelettes et postillons potentiellement infectés visières imprimées par une imprimante 3D offertes. Apple qui a mis en ligne son mode d'emploi (très technique) pour fabriquer des écrans faciaux à destination des professionnels de santé. visières de protection , feuille de PVC cristal transparente Ce groupe a pour vocation de réunir tous les printers et makers disponibles afin de pouvoir répondre aux demandes de matériel médical comme les visières et pieces de respirateur artificiel. Mais aussi d’entraide et de partage de fichiers d’impression, paramètrages et astuces. 3D visières protection - imprimantes 3D - Covid19 Covid-19 - coronavirus - virus