<h2>Abstract</h2><h3>Background</h3> Millions of people have acquired and died from SARS-CoV-2 infection during the COVID-19 pandemic. Healthcare workers (HCWs) are required to wear personal protective equipment (PPE), including surgical masks and P2/N95 respirators, to prevent infection while treating patients. However, the comparative effectiveness of respirators and masks in preventing SARS-CoV-2 infection and the likelihood of experiencing adverse events (AEs) with wear are unclear. <h3>Methods</h3> Searches were carried out in PubMed, Europe PMC and the Cochrane COVID-19 Study Register to 14 June 2021. A systematic review of comparative epidemiological studies examining SARS-CoV-2 infection or AE incidence in HCWs wearing P2/N95 (or equivalent) respirators and surgical masks was performed. Article screening, risk of bias assessment and data extraction were duplicated. Meta-analysis of extracted data was carried out in RevMan. <h3>Results</h3> Twenty-one studies were included, with most having high risk of bias. There was no statistically significant difference in respirator or surgical mask effectiveness in preventing SARS-CoV-2 infection (OR 0.85, [95%CI 0.72, 1.01]). Healthcare workers experienced significantly more headaches (OR 2.62, [95%CI 1.18, 5.81]), respiratory distress (OR 4.21, [95%CI 1.46, 12.13]), facial irritation (OR 1.80, [95%CI 1.03, 3.14]) and pressure-related injuries (OR 4.39, [95%CI 2.37, 8.15]) when wearing respirators compared to surgical masks. <h3>Conclusion</h3> The existing epidemiological evidence does not enable definitive assessment of the effectiveness of respirators compared to surgical masks in preventing infection. Healthcare workers wearing respirators may be more likely to experience AEs. Effective mitigation strategies are important to ensure the uptake and correct use of respirators by HCWs. 

http://www.idhjournal.com.au/article/S2468045122000013/pdf

P2/N95 respirators & surgical masks to prevent SARS-CoV-2 infection: Effectiveness & adverse effects

Background The General Health Questionnaire-12 (GHQ-12) is a widely used instrument to assess mental health status. However, little is known about its applicability in Chinese healthcare workers. This study aimed to evaluate the reliability and validity of the GHQ-12 in Chinese dental healthcare workers. Methods Dental healthcare workers participated in the first occupational survey in China conducted by the Chongqing Stomatological Association from February 2021 to March 2021 by filling out GHQ-12. The reliability and validity of GHQ-12 were then tested. Results A total of 3,020 valid electronic questionnaires were acquired. The positive detection rate of self-reported mental health status was 23.80% (719/3,020). The Cronbach's α coefficient of the GHQ-12 was 0.892, and the Cronbach's α coefficient was 0.877–0.888 after the deletion of individual items, and the split-half reliability was 0.843. The correlation coefficient between the item-total score ranged from 0.465 to 0.762 (P<0.05). The exploratory factor analysis found 2 common factors with a factor load of 0.564–0.818. The confirmatory factor analysis showed that the factor load on the specified items was 0.480–0.790. Conclusions The two-factor model of GHQ-12 featured good reliability and validity, which could be used to assess the mental health status of Chinese dental healthcare workers.

/pdf/reliability-and-validity-of-general-health-questionnaire-12-25f4op9z.pdf

Reliability and Validity of General Health Questionnaire-12 in Chinese Dental Healthcare Workers During the COVID-19 Pandemic

The ongoing COVID-19 pandemic has increased the use of single-use medical fabrics such as surgical masks, respirators, and other personal protective equipment (PPE), which have faced worldwide supply chain shortages. Reusable PPE is desirable in light of such shortages; however, the use of reusable PPE is largely restricted by the difficulty of rapid sterilization. In this work, we demonstrate successful bacterial and viral inactivation through remote and rapid radio frequency (RF) heating of conductive textiles. The RF heating behavior of conductive polymer-coated fabrics was measured for several different fabrics and coating compositions. Next, to determine the robustness and repeatability of this heating response, we investigated the textile's RF heating response after multiple detergent washes. Finally, we show a rapid reduction of bacteria and virus by RF heating our conductive fabric. 99.9% of methicillin-resistant Staphylococcus aureus (MRSA) was removed from our conductive fabrics after only 10 min of RF heating; human cytomegalovirus (HCMV) was completely sterilized after 5 min of RF heating. These results demonstrate that RF heating conductive polymer-coated fabrics offer new opportunities for applications of conductive textiles in the medical and/or electronic fields. 

Radio Frequency Heating of Washable Conductive Textiles for Bacteria and Virus Inactivation

Introduction: dental professionals have been identified as having a very high risk of exposure to coronavirus, specifically when they carry out procedures to generate aerosols in infectious patients. The objective was identifying the mechanical and chemical mechanisms used by Paraguayan dentists to prevent the spread of COVID-19. Evaluate the percentage of dentists who have treated positive COVID patients and who have subsequently developed the disease. Methods: it was a crosssectional descriptive observational study. Paraguayan dentists with internet access participated. The questions were about sociodemographic data and protection measures used in the office to reduce biological risk. The access link was disseminated through social networks. Results: 428 dentists participated in the study, 84.11 % were women, 38.32 % were 30-39 years old. The most used disinfection and care measures were dental chair disinfection (96.7 %), hand washing (93.46 %) and surface disinfection with alcohol 70 (88.08 %). 59.1% used 1% hydrogen peroxide as a preoperative mouthwash. The majority wore KN95 masks (48.83 %), woven cloth robe (78.04 %), disposable robe (72.20 %); The patient is fitted with a disposable surgeon’s cap (89.49 %) and/or shoe covers (76.40 %), and their instruments are sterilized in an autoclave (82.48 %). One professional reported having been infected in the dental office. Conclusion: most of the Paraguayan dentists surveyed comply with the protocols established by the Ministry of Health and international organizations, which appear to be effective as protection mechanisms against COVID-19 in the clinical environment.

Medidas empleadas por odontólogos paraguayos para disminuir el riesgo biológico en la práctica odontológica durante la pandemia.

Size-specific Filtration Efficiency and Pressure Drop of School-aged Children's Woven and Nonwoven Masks at Varying Face Velocities.

OBJECTIVE: Health care professionals and governmental agencies are in consensus regarding contact and droplet transmission of infectious diseases. However, personal protective equipment (PPE) efficacy is not considered for aerosol or airborne transmission of infectious diseases. This review discusses the inhalation of virus-laden aerosols as a viable mechanism of transmission of various respiratory infectious diseases and PPE efficacy. METHODS: The Preferred Reporting Items for Systematic reviews, and Meta-Analysis (PRISMA) guidelines was used. RESULTS: The transmission of infectious disease is of concern for all respirable diseases discussed (SARS-CoV-1, SARS-CoV-2, MERS, influenza, and tuberculosis), and the effectiveness of facemasks is dependent on the efficiency of the filter, fit, and proper use. CONCLUSION: PPE should be the last resort in preventing the spread of infectious disease and should only be used for protection and not to control the transmission.

Laramie Locke

Papers

Aerosol Transmission of Infectious Disease and the Efficacy of Personal Protective Equipment (PPE): A Systematic Review.