2019 Novel Coronavirus (COVID-19) Pandemic: Built Environment Considerations To Reduce Transmission.

With the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that results in coronavirus disease 2019 (COVID-19), corporate entities, federal, state, county, and city governments, universities, school districts, places of worship, prisons, health care facilities, assisted living organizations, daycares, homeowners, and other building owners and occupants have an opportunity to reduce the potential for transmission through built environment (BE)-mediated pathways. Over the last decade, substantial research into the presence, abundance, diversity, function, and transmission of microbes in the BE has taken place and revealed common pathogen exchange pathways and mechanisms. In this paper, we synthesize this microbiology of the BE research and the known information about SARS-CoV-2 to provide actionable and achievable guidance to BE decision makers, building operators, and all indoor occupants attempting to minimize infectious disease transmission through environmentally mediated pathways. We believe this information is useful to corporate and public administrators and individuals responsible for building operations and environmental services in their decision-making process about the degree and duration of social-distancing measures during viral epidemics and pandemics

Viable bacterial communities on hospital window components in patient rooms

Previous studies demonstrate an exchange of bacteria between hospital room surfaces and patients, and a reduction in survival of microorganisms in dust inside buildings from sunlight exposure. While the transmission of microorganisms between humans and their local environment is a continuous exchange which generally does not raise cause for alarm, in a hospital setting with immunocompromised patients, these building-source microbial reservoirs may pose a risk. Window glass is often neglected during hospital disinfection protocols, and the microbial communities found there have not previously been examined. This pilot study examined whether living bacterial communities, and specifically the pathogens Methicillin-resistant Staphylococcus aureus (MRSA) and Clostridioides difficile (C. difficile), were present on window components of exterior-facing windows inside patient rooms, and whether relative light exposure (direct or indirect) was associated with changes in bacterial communities on those hospital surfaces. Environmental samples were collected from 30 patient rooms in a single ward at Oregon Health & Science University (OHSU) in Portland, Oregon, USA. Sampling locations within each room included the window glass surface, both sides of the window curtain, two surfaces of the window frame, and the air return grille. Viable bacterial abundances were quantified using qPCR, and community composition was assessed using Illumina MiSeq sequencing of the 16S rRNA gene V3/V4 region. Viable bacteria occupied all sampled locations, but was not associated with a specific hospital surface or relative sunlight exposure. Bacterial communities were similar between window glass and the rest of the room, but had significantly lower Shannon Diversity, theorized to be related to low nutrient density and resistance to bacterial attachment of glass compared to other surface materials. Rooms with windows that were facing west demonstrated a higher abundance of viable bacteria than those facing other directions, potentially because at the time of sampling (morning) west-facing rooms had not yet been exposed to sunlight that day. Viable C. difficile was not detected and viable MRSA was detected at very low abundance. Bacterial abundance was negatively correlated with distance from the central staff area containing the break room and nursing station. In the present study, it can be assumed that there is more human traffic in the center of the ward, and is likely responsible for the observed gradient of total abundance in rooms along the ward, as healthcare staff both deposit more bacteria during activities and affect microbial transit indoors. Overall, hospital window components possess similar microbial communities to other previously identified room locations known to act as reservoirs for microbial agents of hospital-associated infections

Correction for Dietz et al., "2019 Novel Coronavirus (COVID-19) Pandemic: Built Environment Considerations To Reduce Transmission".

Volume 5, no. 2, e00245-20, 2020, https://doi.org/10.1128/mSystems.00245-20. After original publication of this article, the following changes were made. Page 5, first paragraph, line 18: HEPA filters are rated to remove at least 99.97% of particles down to 0.3 μm (51). Most residential and commercial buildings utilize MERV-5 to MERV-11, and in critical health care settings, MERV-12 or higher and HEPA filters are used. MERV-13 filters have the potential to remove microbes and other particles ranging from 0.3 to 10.0 μm. Most viruses, including CoVs, range from 0.004 to 1.0 μm, limiting the effectiveness of these filtration techniques against pathogens such as SARS-CoV-2 (52). Furthermore, no filter system is perfect. Recently,.... was changed to HEPA filters are rated to remove at least 99.97% of particles at 0.3 μm in size, representing the most penetrating particle size (51). Most residential and commercial buildings utilize MERV-5 to MERV-11, and in critical health care settings, MERV-13 or higher and HEPA filters are used. MERV-13 filters have the potential to remove microbes and other particles ranging from 0.3 to 10.0 μm. Most viruses, including CoVs, range from 0.004 to 1.0 μm (52). However, viruses are rarely observed as individual particles, but instead are expelled from the body already combined with water, proteins, salts, and other components as large droplets and aerosols. Thus far, SARS-CoV-2 has been observed in aerosolized particles in a spectrum of sizes including 0.25 to 0.5 μm (96), necessitating high efficiency filtration techniques to reduce the transmission potential of pathogens such as SARS-CoV-2. However,.... Page 6, third paragraph, second sentence: Even though viral particles are too small to be contained by even the best HEPA and MERV filters, ventilation precautions can be taken to ensure the minimization of SARS-CoV-2 spread. was changed to Viruses are frequently found associated with larger particles (e.g., complexes with water, proteins, salts, etc.) in a range of sizes. Even though some of these particles have been identified in sizes that could potentially penetrate high efficiency filters, ventilation and filtration remain important in reducing the transmission potential of SARS-CoV-2. Page 10, Acknowledgments, first sentence: “We thank Jason Stenson and Cassandra Moseley for comments on the manuscript” was changed to “We thank Jason Stenson, Richard Corsi, Cassandra Moseley, and Linsey Marr for comments on the manuscript

Twenty Important Research Questions in Microbial Exposure and Social Equity

Social and political policy, human activities, and environmental change affect the ways in which microbial communities assemble and interact with people. These factors determine how different social groups are exposed to beneficial and/ or harmful microorganisms, meaning microbial exposure has an important socioecological justice context. Therefore, greater consideration of microbial exposure and social equity in research, planning, and policy is imperative. Here, we identify 20 research questions considered fundamentally important to promoting equitable exposure to beneficial microorganisms, along with safeguarding resilient societies and ecosystems. The 20 research questions we identified span seven broad themes, including the following: (i) sociocultural interactions; (ii) Indigenous community health and well-being; (iii) humans, urban ecosystems, and environmental processes; (iv) human psychology and mental health; (v) microbiomes and infectious diseases; (vi) human health and food security; and (vii) microbiome-related planning, policy, and outreach. Our goal was to summarize this growing field and to stimulate impactful research avenues while providing focus for funders and policymakers