Why so many healthcare workers and their contacts contracted Covid-19 infection despite personal protective equipment?

Overview of tight fit and infection prevention benefits of respirators (filtering face pieces)

Regulations for measures to protect against SARS-CoV-2 transmission vary widely around the world, with very strict regulations in Germany where respirators (filtering face piece FFP2 or comparable) are often mandatory. The efficiency of respirators, however, depends essentially on the tight facial fit avoiding the bypass of contaminated air via gaps between mask and wearer's face. The facial fit can be verified in a fit test. The aim of this review was to describe the quantitative fit test results depending on the respirator designs. A literature search revealed 29 suitable studies. Of all respirators with circumferential head straps, three-panel folded dome-shaped respirators showed the best fit (80.8% of 4625 fit tests passed), followed by rigid-dome-shaped respirators (72.4% of 8234 fit tests passed), duckbill-shaped respirators (31.6% of 2120 fit tests passed), and coffee-filter-shaped respirators (30.9% of 3392 fit tests passed). Respirators with ear loops showed very poor tight fit (3.6% of 222 fit tests passed). In four randomized control trials, single-use respirators were not shown to be superior to surgical masks for the prevention of laboratory-confirmed viral respiratory infections, even when adjusted with a fit test. Therefore, we consider the mandatory use of respirators to be disproportionate and not supported by evidence. Further evidence should be generated, in which scenarios respirators might provide an effective benefit as part of occupational health and safety. For situations with confirmed benefits, only high-quality disposable respirators with head straps or respiratory protective equipment of higher protective levels should be used.

Comparison of the Characteristics of Intubation Airway Barrier Devices Using a Simulated Airway Task Trainer

Background: With the advent of variant strains such as Delta and Omicron, there have been renewed concerns regarding transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) (coronavirus disease 2019 (COVID-19)) disease to healthcare professionals, particularly during intubation procedures. Several forms of barrier protection aimed at decreasing the spread of aerosolized droplets were developed during the early onset of the pandemic.

Objectives: Using a simulated airway model, we examined the impact that three separate barrier devices had on intubation time and success using both direct and video laryngoscopy. We hypothesized that the functionally simplistic devices would be preferred and would allow for faster intubations.

Methods: Just-in-time training sessions focusing on COVID-19 intubations were set up between March and June of 2020. Sixty-seven emergency physicians and anesthesiologists participated. For a subset of physicians, exact times to barrier device setup and both direct and indirect intubations using three different barrier devices were recorded. Subsequently, physicians were asked to fill out a survey regarding their experiences.

Results: The survey response rate was 60%. In general, this cohort preferred a plain clear plastic drape or clear plastic drape with polyvinyl chloride (PVC) cube for direct laryngoscopy and video laryngoscopy setups. The use of these two devices resulted in significantly faster times to completed intubation when compared with the fiberglass box while using a simulated task trainer.

Conclusion: In general, a simple, plastic sheet was the preferred barrier device using video laryngoscopy. Although setup times were faster using the fiberglass box, intubation times were significantly faster using the plastic drape or PVC frame.

COVID-19 pandemic: What can we learn for better air quality and human health?

The COVID-19 lockdown resulted in improved air quality in many cities across the world. With the objective of what could be the new learning from the COVID-19 pandemic and subsequent lockdowns for better air quality and human health, a critical synthesis of the available evidence concerning air pollution reduction, the population at risk and natural versus anthropogenic emissions was conducted. Can the new societal norms adopted during pandemics, such as the use of face cover, awareness regarding respiratory hand hygiene, and physical distancing, help in reducing disease burden in the future? The use of masks will be more socially acceptable during the high air pollution episodes in lower and middle-income countries, which could help to reduce air pollution exposure. Although post-pandemic, some air pollution reduction strategies may be affected, such as car-pooling and the use of mass transit systems for commuting to avoid exposure to airborne infections like coronavirus. However, promoting non-motorized modes of transportation such as cycling and walking within cities as currently being enabled in Europe and other countries could overshadow such losses. This demand focus on increasing walkability in a town for all ages and populations, including for a differently-abled community. The study highlighted that for better health and sustainability there. is also a need to promote other measures such as work-from-home, technological infrastructure, the extension of smart cities, and the use of information technology.