Is face mask with face shield more effective than face mask alone in reducing SARS-CoV-2 transmission? A systematic review

@#<p style="text-align: justify;"><strong>Background.</strong> The use of face shield in addition to face mask is thought to reduce the transmission of SARS-CoV-2 by blocking respiratory droplets and by preventing one from touching facial orifices.</p><p style="text-align: justify;"><strong>Objective.</strong> To determine the effectiveness of face mask with face shield, compared to face mask alone, in reducing transmission of SARS-CoV-2.</p><p style="text-align: justify;"><strong>Methods.</strong> We searched MEDLINE, Cochrane Library, as well as trial registers, preprint sites and COVID-19 living evidence sites as of 30 September 2021. We included studies that used face shield with face mask versus face mask alone to prevent COVID-19. We screened studies, extracted data, assessed the risk of bias and certainty of evidence using the GRADE approach. Review Manager 5.4 was used to estimate pooled effects.</p><p style="text-align: justify;"><strong>Results.</strong> There is no available direct evidence for face shield plus face mask versus face mask alone in the general public. Five (5) observational studies with very low certainty of evidence due to serious risk of bias and indirectness were included. Participants in all the studies were health care workers (HCWs) who used the face shield with their standard personal protective equipment (PPE). Four (4) of the studies were in the hospital setting (three case control studies, one pre- and post-surveillance study); one was done in the community (one pre- and post-surveillance study) in which HCWs visited the residence of the contacts of SARS-CoV-2 positive patients. The case control studies done in the hospital setting showed a trend toward benefit with the use of face shield or goggle but this was inconclusive (OR 0.85, 95% CI 0.68-1.08) while the pre- and post-surveillance study showed significant benefit when face shield (OR 0.28, 95% CI 0.22-0.37) use became a requirement for HCWs upon hospital entry. In the study done in the community setting, significant protection for HCWs was noted with the use of face shield (OR 0.04, 95% CI 0.00-0.69) but the results were limited by serious risk of bias and imprecision.</p><p style="text-align: justify;"><strong>Conclusion.</strong> In the hospital setting, there was a lower likelihood of COVID-19 infection in HCWs who used a face shield or goggles on top of their PPE. For the general public in the community, there is presently no study on the use of face shield in addition to the face mask to prevent COVID-19 infection.</p>

Use of personal protective equipment during surgical procedures including aerosol-generating procedures in reducing the risk of SARS-CoV-2 viral transmission: A rapid review

Introduction@#COVID-19 infection spreads through respiratory droplets, contact, and airborne transmission. During aerosol-generating procedures (AGPs), the risk of spreading SARS-CoV-2 via aerosols is increased significantly. This rapid review determined the association between using personal protective equipment (PPE) during AGPs, including those during surgery, among confirmed or suspected patients with COVID-19 and the risk of infection among healthcare workers. @*Method@#A systematic search of electronic databases MEDLINE, EBSCO, Science Direct, Google Scholar, and Cochrane CENTRAL base was performed last March 21, 2021, using the Boolean combination of keywords for SARS-CoV-2, PPE, and surgery. Two reviewers screened the articles for relevance and extracted the data from the included studies. We critically appraised the included studies using criteria from the Painless Evidence-Based Medicine Evaluation of Articles on Harm. We used RevMan for data pooling, with a 40% heterogeneity cut-off score. GRADEpro guideline development tool determined the quality of evidence of the included studies.@*Results@#Five observational studies investigated the effectiveness of PPE use in reducing SARS-CoV-2 transmission among healthcare workers during any AGPs. The use of N95 masks (OR 0.37 [95% CI 0.21, 0.67], 1 study, n=195), surgical gown (OR 0.59 [95% CI 0.46, 0.77] I2= 0%, 2 studies, n= 941) and gloves (OR 0.42 [95% CI 0.43, 0.55] I2=34%, 3 studies, n=978) versus their non-use significantly reduced the odds of SARS-COV-2 transmission among healthcare workers involved in AGP. Albeit inconclusive due to the very low quality of evidence, using face shields or goggles was not associated with a significant reduction in the odds of SARS-CoV-2 transmission (OR 0.70 [95% CI 0.31, 1.59]) than the non-use of face shields or goggles. The certainty of the overall body of evidence on PPE use in reducing SARS-CoV-2 transmission during AGP procedures was rated very low. In addition, confounders in the assessment could have been using individual PPE with the other standard PPE, compliance of healthcare worker on properly wearing it, and observing other preventive measures.@*Conclusion@#There were lower odds of COVID-19 infection among healthcare workers using appropriate PPE, including N95 respirators, surgical gowns, and gloves during AGPs in suspected or confirmed COVID-19 patients. Several guidelines recommended using enhanced PPE among healthcare workers during surgery despite limited and low-quality evidence. The findings should help in developing recommendations in reducing SARS-CoV-2 transmission in the Philippines. The findings should provide the information needed for healthcare policy decision-making.

Should chest X-ray be used in diagnosing COVID-19?

Key Findings@#While chest x-ray is readily available and may precede RT-PCR test, chest x-ray has low sensitivity early in the COVID-19 disease and shows non-specific lung abnormalities in COVID-19 patients. Chest x-ray is part of the initial diagnostic tool used on COVID-19 patients in some hospitals as it yields fast results compared with reverse transcription-polymerase chain reaction (RT-PCR). Chest Computed Tomography (CT) has been reported to be more sensitive than chest x-ray in determining the presence of COVID-19. Chest x-ray findings in confirmed COVID-19 patients show: Normal lung findings early in the illness and in mildly symptomatic patients. Typical ground-glass opacities and consolidation in the lung periphery. Lung abnormalities are non-specific and may likewise be present in other infections and coronavirus-types of pneumonia. The American College of Radiology (ACR), Center for Disease Control and Prevention (CDC), Canadian Association of Radiologists (CAR), Canadian Society of Thoracic Radiology (CSTR), and British Society of Thoracic Imaging do not recommend the use of chest x-ray to diagnose COVID-19. The Fleisher Society, composed of radiologists and pulmonologists in ten countries, does not recommend a chest x-ray for patients suspected of mild COVID-19. A chest x-ray is recommended for patients with moderate to severe COVID-19 needing immediate triage and patients at high risk for disease progression. Despite presence of chest x-ray findings suggesting COVID-19, RT-PCR test remains the standard diagnostic procedure.