Investigation of the barrier performance of disposable isolation gowns.

BACKGROUND: Recent epidemics and pandemics highlighted the need for effective personal protective equipment, including isolation gowns. The most critical property of an isolation gown is its ability to keep liquids and viruses from passing through the gown. Liquid and viral barrier penetration can be measured using laboratory test methods. Association for the Advancement of Medical Instrumentation (AAMI) PB70 standard defines isolation gown barrier performance levels and requirements. In this study, 22 disposable isolation gown models from 6 manufacturers were tested for liquid and viral penetration resistance. METHODS: Standard test methods were used to evaluate water and viral penetration. Test results were evaluated using AAMI PB70 barrier performance criteria for 4 protection levels. RESULTS: Seven of the 22 tested gown models did not pass liquid and viral penetration testing based on AAMI PB70 at the level claimed by the manufacturer. The majority of these failures occurred at the seam and/or tie attachment areas. CONCLUSIONS: The study findings underscore the need for improved processes surrounding activities such as premarket testing and postmarket evaluation of gowns according to standardized test methods by third-party laboratories. This study also supports the recent Food and Drug Administration guidance document that clarified the characteristics of isolation gowns considered to be class II and subject to Food and Drug Administration premarket review. Infection preventionists, hospital purchasers, and safety professionals should seek isolation gowns demonstrating conformance to industry standards from manufacturers.

Evaluation of fluid leakage at the coverall and glove interface in single and double glove conditions.

BACKGROUND: Fluid leakage through the glove-protective clothing interface is an area of concern for many health care personnel, including emergency medical service providers, who may wear coveralls to protect themselves from multiple types of hazards. There is currently no established standard test method to specifically evaluate the barrier performance of the glove-protective clothing interface region for any personal protective equipment ensemble. OBJECTIVE: This study quantifies the fluid leakage at the coverall and glove interface using single and double gloving. METHODS: A robotic arm, which can simulate upper extremity movements of health care personnel, was used to test 5 coverall models and an extended examination glove model in single and double glove conditions. RESULTS: The results show that there was a significant difference in fluid leakage amounts between some of the coverall models and the number of glove layers studied. Findings also highlight that there is a high correlation between basis weight and stiffness of the coverall fabrics and the fluid leakage amounts. CONCLUSIONS: These results underline that coverall constructed from thin and less stiff fabrics can result in lower fluid leakage levels. Also, there was no significant difference in fluid leakage amounts between single and double gloves when tested with each of the coverall models, with the exception of the coveralls with the highest basis weight and stiffness.

Addressing personal protective equipment (PPE) decontamination: Methylene blue and light inactivates severe acute respiratory coronavirus virus 2 (SARS-CoV-2) on N95 respirators and medical masks with maintenance of integrity and fit.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus. DESIGN: The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance. METHODS: MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method. RESULTS: Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3. CONCLUSIONS: MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.

A simulation study to assess fluid leakage through the glove-gown interface in isolation settings.

BACKGROUND: Isolation gowns are recommended to protect healthcare personnel, patients, and visitors from transfer of microorganisms and body fluids in patient isolation situations. Standards provide limited information about barrier performance of isolation gowns for possible exposure scenarios. One of the most vulnerable areas of the personal protective equipment ensemble is considered the glove-gown interface. However, current isolation gown classification standards do not consider the interface regions of the personal protective equipment system while assessing the level of protection. The purpose of this study was to quantitatively evaluate the fluid leakage through the glove-gown interface by simulating exposures and healthcare personnel arm movements in patient care for isolation settings. METHODS: We tested fluid leakage of two examination gloves with different cuff lengths and seven isolation gown models designed with varying levels of barrier resistance and multiple cuff types. RESULTS: Our results demonstrated that leakage through the glove-gown interface depends on multiple factors, including glove cuff length and gown cuff design. Gowns with the thumb loop design provided better protection than the elastic cuff design, and the elastic cuff design provided better protection compared to the knit cuff design for a given AAMI PB70 level. More importantly, a substantial penetration through gown fabrics was observed. CONCLUSIONS: This research identifies a need to develop a standardized method to evaluate leakage at the glove-gown interface to improve worker protection.

Equipo de protección individual para la prevención de enfermedades altamente infecciosas debidas a la exposición a fluidos corporales contaminados en el personal sanitario / Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff

FUNDAMENTO: El personal sanitario que trata a pacientes con infecciones como el coronavirus (COVID-19) corre el riesgo de infectarse. Este utiliza equipos de protección individual (EPI) para protegerse de las gotas de la tos, los estornudos u otros fluidos corporales de los pacientes infectados y de las superficies contaminadas que puedan infectarlos. El EPI puede incluir delantales, batas o monos (un traje de una sola pieza), guantes, máscaras y equipo de respiración (respiradores) y gafas protectoras. El EPI debe ser puesto correctamente; puede ser incómodo de usar, y los trabajadores de la salud pueden contaminarse cuando se lo quitan. Algunos se han adaptado, por ejemplo, añadiendo pestañas para facilitar su retirada. Las organizaciones como los Centros para el Control y la Prevención de Enfermedades (CDC) de Estados Unidos ofrecen orientación sobre el procedimiento correcto para ponerse y quitarse el EPI. Esta es la actualización de 2020 de una revisión publicada por primera vez en 2016 y actualizada previamente en 2019. ¿QUÉ SE QUERÍA DESCUBRIR?: Se quería saber qué tipo de EPI o combinación de EPI confiere a los trabajadores de la salud la mejor protección; si la modificación del EPI para facilitar su retirada es efectiva; si seguir la guía para retirar el EPI reduce la contaminación; y si el entrenamiento reduce la contaminación. ¿QUÉ SE ENCONTRÓ?: Se encontraron 24 estudios relevantes con 2.278 participantes que evaluaron los tipos de EPI, EPI modificado, procedimientos para poner y quitar el EPI y tipos de entrenamiento. Dieciocho de los estudios no evaluaron a los trabajadores sanitarios que trataban a pacientes infectados, sino que simularon el efecto de la exposición a la infección mediante el uso de marcadores fluorescentes o virus o bacterias inofensivos. La mayoría de los estudios fueron pequeños, y solo 1 o 2 estudios abordaron cada una de las preguntas. TIPOS DE EPI: Cubrir más el cuerpo lleva a una mejor protección. Sin embargo, como esto suele estar asociado con una mayor dificultad para ponerse y quitarse el EPI y una menor comodidad, puede conducir a una mayor contaminación. Los monos son los EPI más difíciles de quitar, pero pueden ofrecer la mejor protección, seguida de los vestidos largos, batas y delantales. Los respiradores que se usan con los monos pueden proteger mejor que una máscara que se usa con una bata, pero son más difíciles de poner. Los tipos de EPI más transpirables pueden conducir a niveles similares de contaminación, pero son más cómodos. La contaminación fue común en la mitad de los estudios a pesar de la mejora del EPI. EPI MODIFICADO: Las batas que tienen guantes adheridos al puño, de manera que los guantes y la bata se quitan juntos y cubren la zona de la muñeca, y las batas que se modifican para que se ajusten bien al cuello pueden reducir la contaminación. Además, añadir lengüetas a los guantes y mascarillas también puede conducir a una menor contaminación. Sin embargo, un estudio no encontró menos errores al ponerse o quitarse las batas modificadas. ORIENTACIÓN SOBRE EL USO DEL EPI: Seguir la guía de los CDC para la eliminación del delantal o la bata, o cualquier instrucción para eliminar el EPI en comparación con las propias preferencias de un individuo, pueden reducir la autocontaminación. Quitarse la bata y los guantes en un solo paso, usar 2 pares de guantes y limpiar los guantes con lejía o desinfectante (pero no con alcohol) también puede reducir la contaminación. ENTRENAMIENTO DE LOS USUARIOS: El entrenamiento en persona, la simulación por computadora y el entrenamiento por video condujeron a menos errores en la extracción del EPI, tanto un entrenamiento entregado como material escrito solamente o una conferencia tradicional. CERTEZA DE LA EVIDENCIA: La certeza (confianza) en las evidencias es limitada porque los estudios simularon la infección (es decir, no fue real), y tuvieron un número de participantes pequeño. ¿QUÉ FALTA DESCUBRIR?: No hubo estudios que investigaran las gafas o las pantallas faciales. No queda claro cuál es la mejor manera de quitarse los EPI después de su uso y el mejor tipo de entrenamiento a largo plazo. Los hospitales deben organizar más estudios, y los investigadores deben ponerse de acuerdo sobre la mejor manera de simular la exposición a un virus. En el futuro, los estudios de simulación deben tener al menos 60 participantes cada uno, y utilizar la exposición a un virus inofensivo para evaluar qué tipo y combinación de EPI protege más. Sería útil que los hospitales pudieran registrar el tipo de EPI utilizado por sus trabajadores para proporcionar información urgente de la vida real. FECHA DE LA BÚSQUEDA: Esta revisión incluye pruebas publicadas hasta el 20 de marzo de 2020

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Barrier resistance of double layer isolation gowns.

BACKGROUND: Isolation gowns are one of the crucial pieces of personal protective equipment (PPE) to prevent the migration of microorganisms and body fluids from patients to health care personnel and vice versa. Underperforming isolation gowns in terms of fluid resistance, could potentially put lives in danger. Wearing multiple layers of isolation gowns could theoretically increase the fluid penetration resistance. This study investigates if 2-layer lower barrier level isolation gowns meet the barrier effectiveness requirements of a single higher barrier level isolation gown. METHODS: Three commonly used ANSI/AAMI Level 2 isolation gown models were selected and tested in single layer and double layer configurations in accordance with ANSI/AAMI PB70 requirements. RESULTS: Total of 240 experiments were conducted to analyze the effects of gown model, fabric region, and the number of gown layers on AATCC 127 and AATCC 42 test results. In regard to AATCC 42, there was a significant difference among the different gown models, and the number of gown layers. Similar to AATCC 42 results, there was a significant difference among the different gown models, and the number of gown layers for AATCC 127; additionally, the gown regions was also significantly different. CONCLUSION: Test results demonstrated that the double layer isolation gown configurations do not always provide equal fluid penetration resistance as required for a single Level 3 isolation gown using the standard test methods specified in ANSI/AAMI PB70.

Planning for Epidemics and Pandemics: Assessing the Potential Impact of Extended Use and Reuse Strategies on Respirator Usage Rates to Support Supply-and-Demand Planning Efforts.

During epidemics and pandemics healthcare personnel (HCP) are on the front line of disease containment and mitigation. Personal protective equipment (PPE), such as NIOSH-approved N95 filtering facepiece respirators (FFRs), serve an important role in minimizing HCP risks and are in high demand during public health emergencies. Because PPE demand can exceed supply, various public health strategies have been developed to reduce the rate of PPE consumption as supply dwindles. Extended use and limited reuse of N95 FFRs are strategies advocated by many governmental agencies used to increase the number of times a device can be used. Increased use of respirators designed for reuse-such as powered air-purifying respirators (PAPRs) and elastomeric half-mask and full facepiece air-purifying respirators- is another option designed to reduce the continuous need for new devices as the daily need for respirator use increases. Together, these strategies are designed to reduce the number of PPE units that must be discarded daily and, therefore, extend the longevity of available supply. The purpose of this paper is to theoretically estimate the impact of extended use and limited reuse strategies for N95 FFRs and the increased use of reusable respirator options on PPE consumed. The results suggest that a considerable reduction in PPE consumption would result from extended use and limited reuse of N95 FFRs and the increased use of respirators designed for reuse; however, the practical benefits must be balanced with the risks and economic costs. In addition, extended use and reuse strategies must be accompanied by proper procedures to reduce risk. The study is designed to support epidemic and pandemic PPE supply and demand planning efforts.

Household Materials Selection for Homemade Cloth Face Coverings and Their Filtration Efficiency Enhancement with Triboelectric Charging.

The COVID-19 pandemic is currently causing a severe disruption and shortage in the global supply chain of necessary personal protective equipment (e.g., N95 respirators). The U.S. CDC has recommended use of household cloth by the general public to make cloth face coverings as a method of source control. We evaluated the filtration properties of natural and synthetic materials using a modified procedure for N95 respirator approval. Common fabrics of cotton, polyester, nylon, and silk had filtration efficiency of 5-25%, polypropylene spunbond had filtration efficiency 6-10%, and paper-based products had filtration efficiency of 10-20%. An advantage of polypropylene spunbond is that it can be simply triboelectrically charged to enhance the filtration efficiency (from 6 to >10%) without any increase in pressure (stable overnight and in humid environments). Using the filtration quality factor, fabric microstructure, and charging ability, we are able to provide an assessment of suggested fabric materials for homemade facial coverings.

Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff.

BACKGROUND: In epidemics of highly infectious diseases, such as Ebola, severe acute respiratory syndrome (SARS), or coronavirus (COVID-19), healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Personal protective equipment (PPE) can reduce the risk by covering exposed body parts. It is unclear which type of PPE protects best, what is the best way to put PPE on (i.e. donning) or to remove PPE (i.e. doffing), and how to train HCWs to use PPE as instructed. OBJECTIVES: To evaluate which type of full-body PPE and which method of donning or doffing PPE have the least risk of contamination or infection for HCW, and which training methods increase compliance with PPE protocols. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase and CINAHL to 20 March 2020. SELECTION CRITERIA: We included all controlled studies that evaluated the effect of full-body PPE used by HCW exposed to highly infectious diseases, on the risk of infection, contamination, or noncompliance with protocols. We also included studies that compared the effect of various ways of donning or doffing PPE, and the effects of training on the same outcomes. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted data and assessed the risk of bias in included trials. We conducted random-effects meta-analyses were appropriate. MAIN RESULTS: Earlier versions of this review were published in 2016 and 2019. In this update, we included 24 studies with 2278 participants, of which 14 were randomised controlled trials (RCT), one was a quasi-RCT and nine had a non-randomised design. Eight studies compared types of PPE. Six studies evaluated adapted PPE. Eight studies compared donning and doffing processes and three studies evaluated types of training. Eighteen studies used simulated exposure with fluorescent markers or harmless microbes. In simulation studies, median contamination rates were 25% for the intervention and 67% for the control groups. Evidence for all outcomes is of very low certainty unless otherwise stated because it is based on one or two studies, the indirectness of the evidence in simulation studies and because of risk of bias. Types of PPE The use of a powered, air-purifying respirator with coverall may protect against the risk of contamination better than a N95 mask and gown (risk ratio (RR) 0.27, 95% confidence interval (CI) 0.17 to 0.43) but was more difficult to don (non-compliance: RR 7.5, 95% CI 1.81 to 31.1). In one RCT (59 participants) coveralls were more difficult to doff than isolation gowns (very low-certainty evidence). Gowns may protect better against contamination than aprons (small patches: mean difference (MD) -10.28, 95% CI -14.77 to -5.79). PPE made of more breathable material may lead to a similar number of spots on the trunk (MD 1.60, 95% CI -0.15 to 3.35) compared to more water-repellent material but may have greater user satisfaction (MD -0.46, 95% CI -0.84 to -0.08, scale of 1 to 5). According to three studies that tested more recently introduced full-body PPE ensembles, there may be no difference in contamination. Modified PPE versus standard PPE The following modifications to PPE design may lead to less contamination compared to standard PPE: sealed gown and glove combination (RR 0.27, 95% CI 0.09 to 0.78), a better fitting gown around the neck, wrists and hands (RR 0.08, 95% CI 0.01 to 0.55), a better cover of the gown-wrist interface (RR 0.45, 95% CI 0.26 to 0.78, low-certainty evidence), added tabs to grab to facilitate doffing of masks (RR 0.33, 95% CI 0.14 to 0.80) or gloves (RR 0.22, 95% CI 0.15 to 0.31). Donning and doffing Using Centers for Disease Control and Prevention (CDC) recommendations for doffing may lead to less contamination compared to no guidance (small patches: MD -5.44, 95% CI -7.43 to -3.45). One-step removal of gloves and gown may lead to less bacterial contamination (RR 0.20, 95% CI 0.05 to 0.77) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28) than separate removal. Double-gloving may lead to less viral or bacterial contamination compared to single gloving (RR 0.34, 95% CI 0.17 to 0.66) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28). Additional spoken instruction may lead to fewer errors in doffing (MD -0.9, 95% CI -1.4 to -0.4) and to fewer contamination spots (MD -5, 95% CI -8.08 to -1.92). Extra sanitation of gloves before doffing with quaternary ammonium or bleach may decrease contamination, but not alcohol-based hand rub. Training The use of additional computer simulation may lead to fewer errors in doffing (MD -1.2, 95% CI -1.6 to -0.7). A video lecture on donning PPE may lead to better skills scores (MD 30.70, 95% CI 20.14 to 41.26) than a traditional lecture. Face-to-face instruction may reduce noncompliance with doffing guidance more (odds ratio 0.45, 95% CI 0.21 to 0.98) than providing folders or videos only. AUTHORS' CONCLUSIONS: We found low- to very low-certainty evidence that covering more parts of the body leads to better protection but usually comes at the cost of more difficult donning or doffing and less user comfort. More breathable types of PPE may lead to similar contamination but may have greater user satisfaction. Modifications to PPE design, such as tabs to grab, may decrease the risk of contamination. For donning and doffing procedures, following CDC doffing guidance, a one-step glove and gown removal, double-gloving, spoken instructions during doffing, and using glove disinfection may reduce contamination and increase compliance. Face-to-face training in PPE use may reduce errors more than folder-based training. We still need RCTs of training with long-term follow-up. We need simulation studies with more participants to find out which combinations of PPE and which doffing procedure protects best. Consensus on simulation of exposure and assessment of outcome is urgently needed. We also need more real-life evidence. Therefore, the use of PPE of HCW exposed to highly infectious diseases should be registered and the HCW should be prospectively followed for their risk of infection.

Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff.

BACKGROUND: In epidemics of highly infectious diseases, such as Ebola, severe acute respiratory syndrome (SARS), or coronavirus (COVID-19), healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Personal protective equipment (PPE) can reduce the risk by covering exposed body parts. It is unclear which type of PPE protects best, what is the best way to put PPE on (i.e. donning) or to remove PPE (i.e. doffing), and how to train HCWs to use PPE as instructed. OBJECTIVES: To evaluate which type of full-body PPE and which method of donning or doffing PPE have the least risk of contamination or infection for HCW, and which training methods increase compliance with PPE protocols. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase and CINAHL to 20 March 2020. SELECTION CRITERIA: We included all controlled studies that evaluated the effect of full-body PPE used by HCW exposed to highly infectious diseases, on the risk of infection, contamination, or noncompliance with protocols. We also included studies that compared the effect of various ways of donning or doffing PPE, and the effects of training on the same outcomes. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted data and assessed the risk of bias in included trials. We conducted random-effects meta-analyses were appropriate. MAIN RESULTS: Earlier versions of this review were published in 2016 and 2019. In this update, we included 24 studies with 2278 participants, of which 14 were randomised controlled trials (RCT), one was a quasi-RCT and nine had a non-randomised design. Eight studies compared types of PPE. Six studies evaluated adapted PPE. Eight studies compared donning and doffing processes and three studies evaluated types of training. Eighteen studies used simulated exposure with fluorescent markers or harmless microbes. In simulation studies, median contamination rates were 25% for the intervention and 67% for the control groups. Evidence for all outcomes is of very low certainty unless otherwise stated because it is based on one or two studies, the indirectness of the evidence in simulation studies and because of risk of bias. Types of PPE The use of a powered, air-purifying respirator with coverall may protect against the risk of contamination better than a N95 mask and gown (risk ratio (RR) 0.27, 95% confidence interval (CI) 0.17 to 0.43) but was more difficult to don (non-compliance: RR 7.5, 95% CI 1.81 to 31.1). In one RCT (59 participants), people with a long gown had less contamination than those with a coverall, and coveralls were more difficult to doff (low-certainty evidence). Gowns may protect better against contamination than aprons (small patches: mean difference (MD) -10.28, 95% CI -14.77 to -5.79). PPE made of more breathable material may lead to a similar number of spots on the trunk (MD 1.60, 95% CI -0.15 to 3.35) compared to more water-repellent material but may have greater user satisfaction (MD -0.46, 95% CI -0.84 to -0.08, scale of 1 to 5). Modified PPE versus standard PPE The following modifications to PPE design may lead to less contamination compared to standard PPE: sealed gown and glove combination (RR 0.27, 95% CI 0.09 to 0.78), a better fitting gown around the neck, wrists and hands (RR 0.08, 95% CI 0.01 to 0.55), a better cover of the gown-wrist interface (RR 0.45, 95% CI 0.26 to 0.78, low-certainty evidence), added tabs to grab to facilitate doffing of masks (RR 0.33, 95% CI 0.14 to 0.80) or gloves (RR 0.22, 95% CI 0.15 to 0.31). Donning and doffing Using Centers for Disease Control and Prevention (CDC) recommendations for doffing may lead to less contamination compared to no guidance (small patches: MD -5.44, 95% CI -7.43 to -3.45). One-step removal of gloves and gown may lead to less bacterial contamination (RR 0.20, 95% CI 0.05 to 0.77) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28) than separate removal. Double-gloving may lead to less viral or bacterial contamination compared to single gloving (RR 0.34, 95% CI 0.17 to 0.66) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28). Additional spoken instruction may lead to fewer errors in doffing (MD -0.9, 95% CI -1.4 to -0.4) and to fewer contamination spots (MD -5, 95% CI -8.08 to -1.92). Extra sanitation of gloves before doffing with quaternary ammonium or bleach may decrease contamination, but not alcohol-based hand rub. Training The use of additional computer simulation may lead to fewer errors in doffing (MD -1.2, 95% CI -1.6 to -0.7). A video lecture on donning PPE may lead to better skills scores (MD 30.70, 95% CI 20.14 to 41.26) than a traditional lecture. Face-to-face instruction may reduce noncompliance with doffing guidance more (odds ratio 0.45, 95% CI 0.21 to 0.98) than providing folders or videos only. AUTHORS' CONCLUSIONS: We found low- to very low-certainty evidence that covering more parts of the body leads to better protection but usually comes at the cost of more difficult donning or doffing and less user comfort, and may therefore even lead to more contamination. More breathable types of PPE may lead to similar contamination but may have greater user satisfaction. Modifications to PPE design, such as tabs to grab, may decrease the risk of contamination. For donning and doffing procedures, following CDC doffing guidance, a one-step glove and gown removal, double-gloving, spoken instructions during doffing, and using glove disinfection may reduce contamination and increase compliance. Face-to-face training in PPE use may reduce errors more than folder-based training. We still need RCTs of training with long-term follow-up. We need simulation studies with more participants to find out which combinations of PPE and which doffing procedure protects best. Consensus on simulation of exposure and assessment of outcome is urgently needed. We also need more real-life evidence. Therefore, the use of PPE of HCW exposed to highly infectious diseases should be registered and the HCW should be prospectively followed for their risk of infection.

Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff.

BACKGROUND: In epidemics of highly infectious diseases, such as Ebola Virus Disease (EVD) or Severe Acute Respiratory Syndrome (SARS), healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Contact precautions by means of personal protective equipment (PPE) can reduce the risk. It is unclear which type of PPE protects best, what is the best way to remove PPE, and how to make sure HCW use PPE as instructed. OBJECTIVES: To evaluate which type of full body PPE and which method of donning or doffing PPE have the least risk of self-contamination or infection for HCW, and which training methods increase compliance with PPE protocols. SEARCH METHODS: We searched MEDLINE (PubMed up to 15 July 2018), Cochrane Central Register of Trials (CENTRAL up to 18 June 2019), Scopus (Scopus 18 June 2019), CINAHL (EBSCOhost 31 July 2018), and OSH-Update (up to 31 December 2018). We also screened reference lists of included trials and relevant reviews, and contacted NGOs and manufacturers of PPE. SELECTION CRITERIA: We included all controlled studies that compared the effects of PPE used by HCW exposed to highly infectious diseases with serious consequences, such as Ebola or SARS, on the risk of infection, contamination, or noncompliance with protocols. This included studies that used simulated contamination with fluorescent markers or a non-pathogenic virus.We also included studies that compared the effect of various ways of donning or doffing PPE, and the effects of training in PPE use on the same outcomes. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies, extracted data and assessed risk of bias in included trials. We planned to perform meta-analyses but did not find sufficiently similar studies to combine their results. MAIN RESULTS: We included 17 studies with 1950 participants evaluating 21 interventions. Ten studies are Randomised Controlled Trials (RCTs), one is a quasi RCT and six have a non-randomised controlled design. Two studies are awaiting assessment.Ten studies compared types of PPE but only six of these reported sufficient data. Six studies compared different types of donning and doffing and three studies evaluated different types of training. Fifteen studies used simulated exposure with fluorescent markers or harmless viruses. In simulation studies, contamination rates varied from 10% to 100% of participants for all types of PPE. In one study HCW were exposed to Ebola and in another to SARS.Evidence for all outcomes is based on single studies and is very low quality.Different types of PPEPPE made of more breathable material may not lead to more contamination spots on the trunk (Mean Difference (MD) 1.60 (95% Confidence Interval (CI) -0.15 to 3.35) than more water repellent material but may have greater user satisfaction (MD -0.46; 95% CI -0.84 to -0.08, scale of 1 to 5).Gowns may protect better against contamination than aprons (MD large patches -1.36 95% CI -1.78 to -0.94).The use of a powered air-purifying respirator may protect better than a simple ensemble of PPE without such respirator (Relative Risk (RR) 0.27; 95% CI 0.17 to 0.43).Five different PPE ensembles (such as gown vs. coverall, boots with or without covers, hood vs. cap, length and number of gloves) were evaluated in one study, but there were no event data available for compared groups.Alterations to PPE design may lead to less contamination such as added tabs to grab masks (RR 0.33; 95% CI 0.14 to 0.80) or gloves (RR 0.22 95% CI 0.15 to 0.31), a sealed gown and glove combination (RR 0.27; 95% CI 0.09 to 0.78), or a better fitting gown around the neck, wrists and hands (RR 0.08; 95% CI 0.01 to 0.55) compared to standard PPE.Different methods of donning and doffing proceduresDouble gloving may lead to less contamination compared to single gloving (RR 0.36; 95% CI 0.16 to 0.78).Following CDC recommendations for doffing may lead to less contamination compared to no guidance (MD small patches -5.44; 95% CI -7.43 to -3.45).Alcohol-based hand rub used during the doffing process may not lead to less contamination than the use of a hypochlorite based solution (MD 4.00; 95% CI 0.47 to 34.24).Additional spoken instruction may lead to fewer errors in doffing (MD -0.9, 95% CI -1.4 to -0.4).Different types of trainingThe use of additional computer simulation may lead to fewer errors in doffing (MD -1.2, 95% CI -1.6 to -0.7).A video lecture on donning PPE may lead to better skills scores (MD 30.70; 95% CI 20.14,41.26) than a traditional lecture.Face to face instruction may reduce noncompliance with doffing guidance more (OR 0.45; 95% CI 0.21 to 0.98) than providing folders or videos only.There were no studies on effects of training in the long term or on resource use.The quality of the evidence is very low for all comparisons because of high risk of bias in all studies, indirectness of evidence, and small numbers of participants. AUTHORS' CONCLUSIONS: We found very low quality evidence that more breathable types of PPE may not lead to more contamination, but may have greater user satisfaction. Alterations to PPE, such as tabs to grab may decrease contamination. Double gloving, following CDC doffing guidance, and spoken instructions during doffing may reduce contamination and increase compliance. Face-to-face training in PPE use may reduce errors more than video or folder based training. Because data come from single small studies with high risk of bias, we are uncertain about the estimates of effects.We still need randomised controlled trials to find out which training works best in the long term. We need better simulation studies conducted with several dozen participants to find out which PPE protects best, and what is the safest way to remove PPE. Consensus on the best way to conduct simulation of exposure and assessment of outcome is urgently needed. HCW exposed to highly infectious diseases should have their use of PPE registered and should be prospectively followed for their risk of infection in the field.

Novel Test Method for the Evaluation of Fluid Leakage at the Glove-Gown Interface and Investigation of Test Parameters.

BACKGROUND: Exposure to patients' blood/body fluids could be life-affecting, when providing care to patients with infectious diseases. Although the glove-gown interface is considered one of the weakest points of the protective ensemble system, there is a lack of research, and existing standards do not provide much guidance on strategies to minimize gaps between the gowns and gloves. Currently, there is no known standard test method to evaluate fluid leakage or assess performance improvements with new gowns/gloves. STUDY DESIGN: A novel test method with a robotic arm, which has the capability to simulate health care personnel's arm movements during fluid exposure, was developed to determine the leakage at the glove-gown interface. This article explains the test method and investigates the effect of movement, exposure type, exposure duration, procedure duration, and existence of pressure on the amount of leaked fluid at the glove-gown interface. RESULTS: Test results suggest that, with the exception of procedure duration, all parameters significantly affected the amount of fluid leaked at the glove-gown interface. Leakage was higher for soaking when compared to spraying, increased as the exposure duration increased, and was greater with the application of pressure. CONCLUSIONS: The novel method developed in this study could be used by manufacturers of personal protective equipment to evaluate their products. Standard development organizations could adapt this test method in their specifications, testing standards, and guidelines.

Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff.

BACKGROUND: In epidemics of highly infectious diseases, such as Ebola Virus Disease (EVD) or SARS, healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Contact precautions by means of personal protective equipment (PPE) can reduce the risk. It is unclear which type of PPE protects best, what is the best way to remove PPE, and how to make sure HCWs use PPE as instructed. OBJECTIVES: To evaluate which type or component of full-body PPE and which method of donning or removing (doffing) PPE have the least risk of self-contamination or infection for HCWs, and which training methods most increase compliance with PPE protocols. SEARCH METHODS: We searched MEDLINE (PubMed up to 8 January 2016), Cochrane Central Register of Trials (CENTRAL up to 20 January 2016), EMBASE (embase.com up to 8 January 2016), CINAHL (EBSCOhost up to 20 January 2016), and OSH-Update up to 8 January 2016. We also screened reference lists of included trials and relevant reviews, and contacted NGOs and manufacturers of PPE. SELECTION CRITERIA: We included all eligible controlled studies that compared the effect of types or components of PPE in HCWs exposed to highly infectious diseases with serious consequences, such as EVD and SARS, on the risk of infection, contamination, or noncompliance with protocols. This included studies that simulated contamination with fluorescent markers or a non-pathogenic virus.We also included studies that compared the effect of various ways of donning or removing PPE, and the effects of various types of training in PPE use on the same outcomes. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies, extracted data and assessed risk of bias in included trials. We intended to perform meta-analyses but we did not find sufficiently similar studies to combine their results. MAIN RESULTS: We included nine studies with 1200 participants evaluating ten interventions. Of these, eight trials simulated the exposure with a fluorescent marker or virus or bacteria containing fluids. Five studies evaluated different types of PPE against each other but two did not report sufficient data. Another two studies compared different types of donning and doffing and three studies evaluated the effect of different types of training.None of the included studies reported a standardised classification of the protective properties against viral penetration of the PPE, and only one reported the brand of PPE used. None of the studies were conducted with HCWs exposed to EVD but in one study participants were exposed to SARS. Different types of PPE versus each otherIn simulation studies, contamination rates varied from 25% to 100% of participants for all types of PPE. In one study, PPE made of more breathable material did not lead to a statistically significantly different number of spots with contamination but did have greater user satisfaction (Mean Difference (MD) -0.46 (95% Confidence Interval (CI) -0.84 to -0.08, range 1 to 5, very low quality evidence). In another study, gowns protected better than aprons. In yet another study, the use of a powered air-purifying respirator protected better than a now outdated form of PPE. There were no studies on goggles versus face shields, on long- versus short-sleeved gloves, or on the use of taping PPE parts together. Different methods of donning and doffing procedures versus each otherTwo cross-over simulation studies (one RCT, one CCT) compared different methods for donning and doffing against each other. Double gloving led to less contamination compared to single gloving (Relative Risk (RR) 0.36; 95% CI 0.16 to 0.78, very low quality evidence) in one simulation study, but not to more noncompliance with guidance (RR 1.08; 95% CI 0.70 to 1.67, very low quality evidence). Following CDC recommendations for doffing led to less contamination in another study (very low quality evidence). There were no studies on the use of disinfectants while doffing. Different types of training versus each otherIn one study, the use of additional computer simulation led to less errors in doffing (MD -1.2, 95% CI -1.6 to -0.7) and in another study additional spoken instruction led to less errors (MD -0.9, 95% CI -1.4 to -0.4). One retrospective cohort study assessed the effect of active training - defined as face-to-face instruction - versus passive training - defined as folders or videos - on noncompliance with PPE use and on noncompliance with doffing guidance. Active training did not considerably reduce noncompliance in PPE use (Odds Ratio (OR) 0.63; 95% CI 0.31 to 1.30) but reduced noncompliance with doffing procedures (OR 0.45; 95% CI 0.21 to 0.98, very low quality evidence). There were no studies on how to retain the results of training in the long term or on resource use.The quality of the evidence was very low for all comparisons because of high risk of bias in studies, indirectness of evidence, and small numbers of participants. This means that it is likely that the true effect can be substantially different from the one reported here. AUTHORS' CONCLUSIONS: We found very low quality evidence that more breathable types of PPE may not lead to more contamination, but may have greater user satisfaction. We also found very low quality evidence that double gloving and CDC doffing guidance appear to decrease the risk of contamination and that more active training in PPE use may reduce PPE and doffing errors more than passive training. However, the data all come from single studies with high risk of bias and we are uncertain about the estimates of effects.We need simulation studies conducted with several dozens of participants, preferably using a non-pathogenic virus, to find out which type and combination of PPE protects best, and what is the best way to remove PPE. We also need randomised controlled studies of the effects of one type of training versus another to find out which training works best in the long term. HCWs exposed to highly infectious diseases should have their use of PPE registered and should be prospectively followed for their risk of infection.

Isolation gowns in health care settings: Laboratory studies, regulations and standards, and potential barriers of gown selection and use.

Although they play an important role in infection prevention and control, textile materials and personal protective equipment (PPE) used in health care settings are known to be one of the sources of cross-infection. Gowns are recommended to prevent transmission of infectious diseases in certain settings; however, laboratory and field studies have produced mixed results of their efficacy. PPE used in health care is regulated as either class I (low risk) or class II (intermediate risk) devices in the United States. Many organizations have published guidelines for the use of PPE, including isolation gowns, in health care settings. In addition, the Association for the Advancement of Medical Instrumentation published a guidance document on the selection of gowns and a classification standard on liquid barrier performance for both surgical and isolation gowns. However, there is currently no existing standard specific to isolation gowns that considers not only the barrier resistance but also a wide array of end user desired attributes. As a result, infection preventionists and purchasing agents face several difficulties in the selection process, and end users have limited or no information on the levels of protection provided by isolation gowns. Lack of knowledge about the performance of protective clothing used in health care became more apparent during the 2014 Ebola epidemic. This article reviews laboratory studies, regulations, guidelines and standards pertaining to isolation gowns, characterization problems, and other potential barriers of isolation gown selection and use.