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Jiang H, Cui H, Chen M, Li F, Shen X, Guo CJ, Hoekel GE, Zhu Y, Han L, Wu K, Holtzman MJ, Liu Q. Divergent sensory pathways of sneezing and coughing. Cell 2024:S0092-8674(24)00900-0. [PMID: 39243765 DOI: 10.1016/j.cell.2024.08.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 06/25/2024] [Accepted: 08/07/2024] [Indexed: 09/09/2024]
Abstract
Sneezing and coughing are primary symptoms of many respiratory viral infections and allergies. It is generally assumed that sneezing and coughing involve common sensory receptors and molecular neurotransmission mechanisms. Here, we show that the nasal mucosa is innervated by several discrete populations of sensory neurons, but only one population (MrgprC11+MrgprA3-) mediates sneezing responses to a multitude of nasal irritants, allergens, and viruses. Although this population also innervates the trachea, it does not mediate coughing, as revealed by our newly established cough model. Instead, a distinct sensory population (somatostatin [SST+]) mediates coughing but not sneezing, unraveling an unforeseen sensory difference between sneezing and coughing. At the circuit level, sneeze and cough signals are transmitted and modulated by divergent neuropathways. Together, our study reveals the difference in sensory receptors and neurotransmission/modulation mechanisms between sneezing and coughing, offering neuronal drug targets for symptom management in respiratory viral infections and allergies.
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Affiliation(s)
- Haowu Jiang
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Huan Cui
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Mengyu Chen
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Fengxian Li
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Xiaolei Shen
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Changxiong J Guo
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - George E Hoekel
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Yuyan Zhu
- The School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Liang Han
- The School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Kangyun Wu
- Pulmonary and Critical Care Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Michael J Holtzman
- Pulmonary and Critical Care Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Qin Liu
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA.
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Shu H, Yu X, Zhu X, Zhang F, He J, Duan X, Liu M, Li J, Yang W, Zhao J. Visualisation of Droplet Flow Induced by Ultrasonic Dental Cleaning. Int Dent J 2024; 74:876-883. [PMID: 38238210 PMCID: PMC11287087 DOI: 10.1016/j.identj.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/10/2023] [Accepted: 12/22/2023] [Indexed: 07/07/2024] Open
Abstract
INTRODUCTION During dental treatment procedures ultrasonic scalers generate droplets containing microorganisms such as bacteria and viruses. Hence, it is necessary to study the dynamic properties of generated droplets in order to investigate the risks associated with the spread of infection. The aim of this study was to visualise the flow state of droplets and to evaluate the impact of droplets generated during the use of an ultrasonic scaler during an oral surgical procedure. METHODS We studied the spatial flow of liquid droplets through a combination of imaging and numeric simulation of a simulated dental treatment processes. First, we photographed the real time images of the ultrasonic scaler and evaluated the images using image-processing software Image J to visualise the flow of liquid droplets. Finally we simulated the flow process of liquid droplets by using the initial velocity of droplet splashing and the angle of the obtained information using computerised fluid dynamics technology. RESULTS Under different working conditions, the droplet particle splashing velocity, maximum height, and spray angle varied, but the particle trajectory was generally parabolic. The maximum droplet velocity varied between 3.56 and 8.56 m/s, and the splashing height was between 40 and 110 mm. CONCLUSIONS During risk assessment of an ultrasonic scaler usage, difficulties arise due to the insufficient research on droplet velocity and distribution. This study aims to address this gap by visualising the flow trajectories of droplets generated by ultrasonic scalers. The obtained data will assist in developing more effective interventions based on spatial and temporal distribution of droplets. This provides a new approach for droplet particle research and offers new strategies for public health prevention and control.
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Affiliation(s)
- Haiyin Shu
- Guizhou University Medical College, Guiyang, Guizhou, China
| | - Xiaoyan Yu
- Guiyang Hospital of Stomatology, Guiyang, Guizhou, China
| | - Xiankun Zhu
- Guiyang Hospital of Stomatology, Guiyang, Guizhou, China
| | - Fan Zhang
- School of Mechanical Engineering, Guizhou University, Guiyang, Guizhou, China
| | - Junjie He
- School of Mechanical Engineering, Guizhou University, Guiyang, Guizhou, China
| | - Xubo Duan
- Guizhou University Medical College, Guiyang, Guizhou, China
| | - Mingkun Liu
- Guizhou University Medical College, Guiyang, Guizhou, China
| | - Jiachun Li
- School of Mechanical Engineering, Guizhou University, Guiyang, Guizhou, China
| | - Wei Yang
- Guizhou University Medical College, Guiyang, Guizhou, China; Guiyang Hospital of Stomatology, Guiyang, Guizhou, China.
| | - Jin Zhao
- School of Mechanical Engineering, Guizhou University, Guiyang, Guizhou, China.
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Zhang Y, Feng W. Impact of the coronavirus disease 2019 pandemic on the diversity of notifiable infectious diseases: a case study in Shanghai, China. PeerJ 2024; 12:e17124. [PMID: 38495754 PMCID: PMC10941765 DOI: 10.7717/peerj.17124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 02/26/2024] [Indexed: 03/19/2024] Open
Abstract
The outbreak of coronavirus disease 2019 (COVID-19) has not only posed significant challenges to public health but has also impacted every aspect of society and the environment. In this study, we propose an index of notifiable disease outbreaks (NDOI) to assess the impact of COVID-19 on other notifiable diseases in Shanghai, China. Additionally, we identify the critical factors influencing these diseases using multivariate statistical analysis. We collected monthly data on 34 notifiable infectious diseases (NIDs) and corresponding environmental and socioeconomic factors (17 indicators) from January 2017 to December 2020. The results revealed that the total number of cases and NDOI of all notifiable diseases decreased by 47.1% and 52.6%, respectively, compared to the period before the COVID-19 pandemic. Moreover, the COVID-19 pandemic has led to improved air quality as well as impacted the social economy and human life. Redundancy analysis (RDA) showed that population mobility, particulate matter (PM2.5), atmospheric pressure, and temperature were the primary factors influencing the spread of notifiable diseases. The NDOI is beneficial in establishing an early warning system for infectious disease epidemics at different scales. Furthermore, our findings also provide insight into the response mechanisms of notifiable diseases influenced by social and environmental factors.
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Affiliation(s)
- Yongfang Zhang
- School of Chemistry and Chemical Engineering, Zhoukou Normal University, Zhoukou, China
| | - Wenli Feng
- School of Chemistry and Chemical Engineering, Zhoukou Normal University, Zhoukou, China
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4
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Shahzad M, Saeed M, Amin H, Binmadi N, Ullah Z, Bibi S, Andrew SC. The oral microbiome of newly diagnosed tuberculosis patients; a pilot study. Genomics 2024; 116:110816. [PMID: 38431030 DOI: 10.1016/j.ygeno.2024.110816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/15/2024] [Accepted: 02/25/2024] [Indexed: 03/05/2024]
Abstract
BACKGROUND Changes in oral microbiota composition (dysbiosis) have long been known to play a key role in the pathogenesis of oral and systemic diseases including respiratory diseases. However, till now, no study has assessed changes in oral microbiota following tuberculosis (TB) infection in humans. AIMS This is the first study of its kind that aimed to investigate oral microbial dysbiosis in newly diagnosed, treatment naïve, TB patients. METHODS Oral swab samples were collected from newly diagnosed TB patients (n = 20) and age, gender and ethnicity matched healthy controls (n = 10). DNA was extracted and microbiota analyzed by sequencing the hypervariable (V3-V4) region of the bacterial 16S rRNA gene using Illumina MiSeq platform. Bioinformatics and statistical analyses were performed using QIIME and R. RESULTS Bacterial richness, diversity and community composition were significantly different between TB patients and healthy controls. The two groups also exhibit differential abundance at phylum, class, genus and species levels. LEfSe analysis revealed enrichment (LDA scores (log10) >2, P < 0.05) of Firmicutes (especially Streptococcus) and Actinobacteriota (especially Rothia) in TB patients relative to healthy controls. Gene function prediction analysis showed upregulation of metabolic pathways related to carbohydrates (butanoate, galactose) and fatty acids metabolism, antibiotics biosynthesis, proteosome and immune system signaling. CONCLUSION These observations suggest significant variations in diversity, relative abundance and functional potential of oral microbiota of TB patients compared to healthy controls thereby suggesting potential role of oral bacterial dysbiosis in TB pathogenesis. However, longitudinal studies using powerful metagenomic and transcriptomic approaches are crucial to more fully understand and confrim these findings.
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Affiliation(s)
- Muhammad Shahzad
- Faculty of Dentistry, Zarqa University, Zarqa 13110, Jordan; Institute of Basic Medical Sciences, Khyber Medical University, Hayat Abad Phase 5, Peshawar 25120, Pakistan.
| | - Muhammad Saeed
- Institute of Basic Medical Sciences, Khyber Medical University, Hayat Abad Phase 5, Peshawar 25120, Pakistan
| | - Humaira Amin
- Alpha Genomics Private Limited, Islamabad 45710, Pakistan
| | - Nada Binmadi
- Department of Oral Diagnostic Sciences, King Abdulaziz University Faculty of Dentistry, Jeddah, Saudi Arabia
| | - Zafar Ullah
- Institute of Basic Medical Sciences, Khyber Medical University, Hayat Abad Phase 5, Peshawar 25120, Pakistan
| | - Sana Bibi
- Alpha Genomics Private Limited, Islamabad 45710, Pakistan
| | - Simon C Andrew
- School of Biological Sciences, Health and Life Sciences Building, University of Reading, Reading RG6 6EX, UK.
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5
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Reissner J, Siller P, Bartel A, Roesler U, Friese A. Stability of Feline Coronavirus in aerosols and dried in organic matrices on surfaces at various environmental conditions. Sci Rep 2023; 13:22012. [PMID: 38086913 PMCID: PMC10716419 DOI: 10.1038/s41598-023-49361-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 12/07/2023] [Indexed: 12/18/2023] Open
Abstract
Enveloped respiratory viruses, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can be transmitted through aerosols and contact with contaminated surfaces. The stability of these viruses outside the host significantly impacts their transmission dynamics and the spread of diseases. In this study, we investigated the tenacity of Feline Coronavirus (FCoV) in aerosols and on surfaces under varying environmental conditions. We found that airborne FCoV showed different stability depending on relative humidity (RH), with higher stability observed at low and high RH. Medium RH conditions (50-60%) were associated with increased loss of infectivity. Furthermore, FCoV remained infectious in the airborne state over 7 h. On stainless-steel surfaces, FCoV remained infectious for several months, with stability influenced by organic material and temperature. The presence of yeast extract and a temperature of 4 °C resulted in the longest maintenance of infectivity, with a 5 log10 reduction of the initial concentration after 167 days. At 20 °C, this reduction was achieved after 19 days. These findings highlight the potential risk of aerosol and contact transmission of respiratory viruses, especially in enclosed environments, over extended periods. Studying surrogate viruses like FCoV provides important insights into the behavior of zoonotic viruses like SARS-CoV-2 in the environment.
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Affiliation(s)
- Janina Reissner
- Institute of Animal Hygiene and Environmental Health, Veterinary Centre for Resistance Research-TZR, School of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany.
| | - Paul Siller
- Institute of Animal Hygiene and Environmental Health, Veterinary Centre for Resistance Research-TZR, School of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
- Federal Office of Consumer Protection and Food Safety, Department Veterinary Drugs, Mittelstraße 51-54, 10117, Berlin, Germany
| | - Alexander Bartel
- Institute of Veterinary Epidemiology and Biostatistics, School of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
| | - Uwe Roesler
- Institute of Animal Hygiene and Environmental Health, Veterinary Centre for Resistance Research-TZR, School of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
| | - Anika Friese
- Institute of Animal Hygiene and Environmental Health, Veterinary Centre for Resistance Research-TZR, School of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
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Kumar MS, He R, Feng L, Olin P, Chew HP, Jardine P, Anderson GC, Hong J. Particle generation and dispersion from high-speed dental drilling. Clin Oral Investig 2023; 27:5439-5448. [PMID: 37479870 DOI: 10.1007/s00784-023-05163-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 07/13/2023] [Indexed: 07/23/2023]
Abstract
OBJECTIVE To investigate the characteristics of particle generation and dispersion during dental procedure using digital inline holography (DIH) METHODS: Particles at two locations, near-field and far-field, which represent the field closer to the procedure location and within 0.5 m from the procedure location respectively, are studied using two different DIH systems. The effect of three parameters namely rotational speed, coolant flow rate, and bur angle on particle generation and dispersion are evaluated by using 10 different operating conditions. The particle characteristics at different operating conditions are estimated from the holograms using machine learning-based analysis. RESULTS The particle concentration decreased by at least two orders of magnitude between the near-field and far-field locations across the 10 different operating conditions, indicating significant dispersion of the particles. High rotational speed is found to produce a larger number of smaller particles, while lower rotational speeds generate larger particles. Coolant flow rate is found to have a greater impact on particle transport to the far-field location. Irregular shape dental particles account for 29% of total particles at far-field location, with the majority of these irregular shape particles having diameters ranging from 12 to 18 μm. CONCLUSIONS All three parameters have significant effects on particle generation and dispersion, with rotational speed having a more significant influence on particle generation at near-field and coolant flow rate playing a more important role on particle transport to the far-field. CLINICAL RELEVANCE This study provides valuable insights on particle characteristics during high-speed drilling. It can help dental professionals minimize exposure risks for themselves and patients by optimizing clinical operating conditions.
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Affiliation(s)
- M Shyam Kumar
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Ruichen He
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA
| | - Lei Feng
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA
| | - Paul Olin
- University of Minnesota School of Dentistry, Minneapolis, MN, USA
| | - Hooi Pin Chew
- University of Minnesota School of Dentistry, Minneapolis, MN, USA
| | - Paul Jardine
- University of Minnesota School of Dentistry, Minneapolis, MN, USA
| | - Gary C Anderson
- University of Minnesota School of Dentistry, Minneapolis, MN, USA
| | - Jiarong Hong
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, USA.
- Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA.
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Marco L, Cambien G, Garcia M, Broutin L, Cateau E, Lariviere A, Castel O, Thevenot S, Bousseau A. [Respiratory infections: Additional transmission-based precautions in healthcare facilities]. Rev Mal Respir 2023; 40:572-603. [PMID: 37365075 DOI: 10.1016/j.rmr.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 05/04/2023] [Indexed: 06/28/2023]
Abstract
INTRODUCTION In health care, measures against cross-transmission of microorganisms are codified by standard precautions, and if necessary, they are supplemented by additional precautions. STATE OF THE ART Several factors impact transmission of microorganisms via the respiratory route: size and quantity of the emitted particles, environmental conditions, nature and pathogenicity of the microorganisms, and degree of host receptivity. While some microorganisms necessitate additional airborne or droplet precautions, others do not. PROSPECTS For most microorganisms, transmission patterns are well-understood and transmission-based precautions are well-established. For others, measures to prevent cross-transmission in healthcare facilities remain under discussion. CONCLUSIONS Standard precautions are essential to the prevention of microorganism transmission. Understanding of the modalities of microorganism transmission is essential to implementation of additional transmission-based precautions, particularly in view of opting for appropriate respiratory protection.
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Affiliation(s)
- L Marco
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - G Cambien
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Inserm CIC 1402, université de Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - M Garcia
- Département des agents infectieux, laboratoire de virologie et mycobactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Laboratoire inflammation, tissus épithéliaux et cytokines, EA 4331, université de Poitiers, 86021 Poitiers, France
| | - L Broutin
- Département des agents infectieux, laboratoire de bactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - E Cateau
- Laboratoire écologie et biologie des interactions, UMR CNRS 7267, université de Poitiers, 86021 Poitiers, France; Département des agents infectieux, laboratoire de parasitologie et mycologie médicale, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - A Lariviere
- Département des agents infectieux, laboratoire de virologie et mycobactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - O Castel
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - S Thevenot
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Inserm CIC 1402, université de Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - A Bousseau
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France.
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Van der Weijden F. Aerosol in the oral health-care setting: a misty topic. Clin Oral Investig 2023:10.1007/s00784-023-05034-x. [PMID: 37162570 PMCID: PMC10170433 DOI: 10.1007/s00784-023-05034-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/18/2023] [Indexed: 05/11/2023]
Abstract
Studies have shown that mouth and respiratory tract microorganisms can be transported in aerosol and spatter. Due to aerosol-generating procedures, there are potentially various infection risks for patients and those working in health care, especially in oral health care. Dental aerosol can contaminate not only the mucous membranes of the oral health-care professional's mouth, respiratory passages, and eyes but also exposed surfaces and materials in the environment. As such, preventing disease transmission within oral health-care offices is important issue. Since the start of the COVID-19 pandemic, an innumerable amount of (mis)information and advice on how to stay safe and prevent the spread of coronavirus has been published. What preventive measures can and have been taken to counteract this, and what have we learned during the pandemic? This review summarizes relevant literature that has addressed the presence and dispersal of aerosol and spatter as a concern in health care. It includes the sources of dental aerosol, their potential health threats, and strategies for controlling and mitigating their impact. It shows that further research is needed to better understand the potential health risks of dental aerosol and to develop effective strategies for mitigating them. CLINICAL RELEVANCE: Using personal protective equipment, high-volume evacuation systems and pre-procedural antimicrobial agents can help to reduce the potential for infection in oral health-care settings and protect the well-being of oral health-care workers and their patients.
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Affiliation(s)
- Fridus Van der Weijden
- Department of Periodontology, Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
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Liu Z, Lv J, Zhang Z, Ma J, Song Y, Wu M, Cao G, Guo J. Three Experimental Common High-Risk Procedures: Emission Characteristics Identification and Source Intensity Estimation in Biosafety Laboratory. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4479. [PMID: 36901493 PMCID: PMC10002466 DOI: 10.3390/ijerph20054479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/19/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Biosafety laboratory is an important place to study high-risk microbes. In biosafety laboratories, with the outbreak of infectious diseases such as COVID-19, experimental activities have become increasingly frequent, and the risk of exposure to bioaerosols has increased. To explore the exposure risk of biosafety laboratories, the intensity and emission characteristics of laboratory risk factors were investigated. In this study, high-risk microbe samples were substituted with Serratia marcescens as the model bacteria. The resulting concentration and particle size segregation of the bioaerosol produced by three experimental procedures (spill, injection, and sample drop) were monitored, and the emission sources' intensity were quantitatively analyzed. The results showed that the aerosol concentration produced by injection and sample drop was 103 CFU/m3, and that by sample spill was 102 CFU/m3. The particle size of bioaerosol is mainly segregated in the range of 3.3-4.7 μm. There are significant differences in the influence of risk factors on source intensity. The intensity of sample spill, injection, and sample drop source is 3.6 CFU/s, 78.2 CFU/s, and 664 CFU/s. This study could provide suggestions for risk assessment of experimental operation procedures and experimental personnel protection.
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Affiliation(s)
- Zhijian Liu
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Jiabin Lv
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Zheng Zhang
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Juntao Ma
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Yangfan Song
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Minnan Wu
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
| | - Guoqing Cao
- Institute of Building Environment and Energy, China Academy of Building Research, Beijing 100013, China
| | - Jiacheng Guo
- Department of Power Engineering, North China Electric Power University, Baoding 071003, China
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10
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Tandjaoui-Lambiotte Y, Lomont A, Moenne-Locoz P, Seytre D, Zahar JR. Spread of viruses, which measures are the most apt to control COVID-19? Infect Dis Now 2023; 53:104637. [PMID: 36526247 PMCID: PMC9746078 DOI: 10.1016/j.idnow.2022.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/22/2022] [Accepted: 12/06/2022] [Indexed: 12/15/2022]
Abstract
The persistent debate about the modes of transmission of SARS-CoV2 and preventive measures has illustrated the limits of our knowledge regarding the measures to be implemented in the face of viral risk. Past and present (pandemic-related) scientific data underline the complexity of the phenomenon and its variability over time. Several factors contribute to the risk of transmission, starting with incidence in the general population (i.e., colonization pressure) and herd immunity. Other major factors include intensity of symptoms, interactions with the reservoir (proximity and duration of contact), the specific characteristics of the virus(es) involved, and a number of unpredictable elements (humidity, temperature, ventilation…). In this review, we will emphasize the difficulty of "standardizing" the situations that might explain the discrepancies found in the literature. We will show that the airborne route remains the main mode of transmission. Regarding preventive measures of prevention, while vaccination remains the cornerstone of the fight against viral outbreaks, we will remind the reader that wearing a mask is the main barrier measure and that the choice of type of mask depends on the risk situations. Finally, we believe that the recent pandemic should induce us in the future to modify our recommendations by adapting our measures in hospitals, not to the pathogen concerned, which is currently the case, but rather to the type of at-risk situation.
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Affiliation(s)
- Y Tandjaoui-Lambiotte
- Service de Pneumologie-Infectiologie, CH Saint Denis, 2 rue Dr. Delafontaine, 93200, France
| | - A Lomont
- Unité de Prévention du Risque Infectieux, Service de microbiologie clinique, GHU Paris Seine Saint-Denis, Université Sorbonne Paris Nord, France
| | - P Moenne-Locoz
- Unité de Prévention du Risque Infectieux, Service de microbiologie clinique, GHU Paris Seine Saint-Denis, Université Sorbonne Paris Nord, France
| | - D Seytre
- Unité de Prévention du Risque Infectieux, Service de microbiologie clinique, GHU Paris Seine Saint-Denis, Université Sorbonne Paris Nord, France
| | - J R Zahar
- Unité de Prévention du Risque Infectieux, Service de microbiologie clinique, GHU Paris Seine Saint-Denis, Université Sorbonne Paris Nord, France.
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11
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Issakhov A, Omarova P, Abylkassymova A. Numerical simulation of social distancing of preventing airborne transmission in open space with lateral wind direction, taking into account temperature of human body and floor surface. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:33206-33228. [PMID: 36478554 PMCID: PMC9734804 DOI: 10.1007/s11356-022-24067-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
This paper presents the numerical results of particle propagation in open space, taking into account the temperature of the human body and the surface of the ground. And also, the settling of particles or droplets under the action of gravitational force and transport in the open air is taken into account, taking into account the temperature during the process of breathing and sneezing or coughing. The temperature of the body and the surface of the ground, different rates of particle emission from the mouth, such as breathing and coughing or sneezing, are numerically investigated. The effect of temperature, cross-inlet wind, and the velocity of particle ejection from a person's mouth on social distancing is being investigated using a numerical calculation. The variable temperature of the human body forms a thermal plume, which affects the increase in the trajectory of the particle propagation, taking into account the lateral air flow. The thermal plume affects the particles in the breathing zone and spreads the particles over long distances in the direction of the airflow. The result of this work shows that in open space, taking into account the temperature of the body and the surface of the ground, a 2-m social distance may be insufficient for the process of sneezing and social distance must be observed depending on the breathing mode.
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Affiliation(s)
- Alibek Issakhov
- Al-Farabi Kazakh National University, Almaty, Republic of Kazakhstan
- Present Address: Kazakh British Technical University, Almaty, Republic of Kazakhstan
- International Information Technology University, Almaty, Republic of Kazakhstan
| | - Perizat Omarova
- Al-Farabi Kazakh National University, Almaty, Republic of Kazakhstan
| | - Aizhan Abylkassymova
- Present Address: Kazakh British Technical University, Almaty, Republic of Kazakhstan
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12
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Sanmark E, Kuula J, Laitinen S, Oksanen LMAH, Bamford DH, Atanasova NS. Safe use of PHI6 IN the experimental studies. Heliyon 2023; 9:e13565. [PMID: 36879750 PMCID: PMC9984441 DOI: 10.1016/j.heliyon.2023.e13565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/02/2023] [Accepted: 02/02/2023] [Indexed: 02/09/2023] Open
Abstract
Surrogate viruses theoretically provide an opportunity to study the viral spread in an indoor environment, a highly needed understanding during the pandemic, in a safe manner to humans and the environment. However, the safety of surrogate viruses for humans as an aerosol at high concentrations has not been established. In this study, Phi6 surrogate was aerosolized at high concentration (Particulate matter2.5: ∼1018 μg m-3) in the studied indoor space. Participants were closely followed for any symptoms. We measured the bacterial endotoxin concentration of the virus solution used for aerosolization as well as the concentration in the room air containing the aerosolized viruses. In addition, we measured how the bacterial endotoxin concentration of the sample was affected by different traditional virus purification procedures. Despite the purification, bacterial endotoxin concentration of the Phi6 was high (350 EU/ml in solution used for aerosols) with both (two) purification protocols. Bacterial endotoxins were also detected in aerosolized form, but below the occupational exposure limit of 90 EU/m3. Despite these concerns, no symptoms were observed in exposed humans when they were using personal protective equipment. In the future, purification protocols should be developed to reduce associated bacterial endotoxin levels in enveloped bacterial virus specimens to ensure even safer research use of surrogate viruses.
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Affiliation(s)
- Enni Sanmark
- University of Helsinki, Faculty of Medicine, Helsinki, Finland.,Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Joel Kuula
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
| | - Sirpa Laitinen
- Finnish Institute of Occupational Health, Kuopio, Finland
| | - Lotta-Maria A H Oksanen
- University of Helsinki, Faculty of Medicine, Helsinki, Finland.,Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Dennis H Bamford
- Molecular and Integrative Biosciences Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Nina S Atanasova
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland.,Molecular and Integrative Biosciences Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
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13
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Chillón SA, Fernandez-Gamiz U, Zulueta E, Ugarte-Anero A, Urbina-Garcia O. Numerical modeling of a sneeze, a cough and a continuum speech inside a hospital lift. Heliyon 2023; 9:e13370. [PMID: 36744064 PMCID: PMC9889118 DOI: 10.1016/j.heliyon.2023.e13370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 01/13/2023] [Accepted: 01/28/2023] [Indexed: 02/04/2023] Open
Abstract
The global COVID-19 and its variants put us on notice of the importance of studying the spread of respiratory diseases. The most common means of propagation was the emission of droplets due to different respiration activities. This study modeled by computational fluid dynamics (CFD) techniques a high risk scenario like a hospital elevator. The cabin was provided with an extraction fan and a rack for air renewal. Inside, a sneeze, a cough and a continuum speech were simulated. Inside the lift, two occupants were introduced to observe the risk of propagation of emitted droplets and the impact in diseases spreading risk. The fan effectivity over the droplets ejection was analyzed, as well as environmental condition of a clinical setting. For this purpose the amount of droplets inside were counted during whole time of simulations. The effect of the fan was concluded as able to eject the 60% of small droplets, but also a high performance in spreading particles inside. Among the three cases, the riskiest scenario was the continuum speech due to the saturation of droplets in airborne.
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Affiliation(s)
- Sergio A. Chillón
- Nuclear Engineering and Fluid Mechanics Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Araba, Spain
| | - Unai Fernandez-Gamiz
- Nuclear Engineering and Fluid Mechanics Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Araba, Spain,Corresponding author
| | - Ekaitz Zulueta
- Automatic and Simulation Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Araba, Spain
| | - Ainara Ugarte-Anero
- Nuclear Engineering and Fluid Mechanics Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Araba, Spain
| | - Oskar Urbina-Garcia
- Nuclear Engineering and Fluid Mechanics Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, Vitoria-Gasteiz, 01006, Araba, Spain
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14
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Uddin MN, Emran TB. Prevention of Progression and Remission in Public Health Sectors: Bangladesh Perspectives. ATLANTIS HIGHLIGHTS IN CHEMISTRY AND PHARMACEUTICAL SCIENCES 2023:131-150. [DOI: 10.2991/978-94-6463-130-2_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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15
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Wang B, Yang D, Chang Z, Zhang R, Dai J, Fang Y. Wearable bioelectronic masks for wireless detection of respiratory infectious diseases by gaseous media. MATTER 2022; 5:4347-4362. [PMID: 36157685 PMCID: PMC9484046 DOI: 10.1016/j.matt.2022.08.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/07/2022] [Accepted: 08/16/2022] [Indexed: 05/17/2023]
Abstract
Respiratory infectious diseases (H1N1, H5N1, COVID-19, etc.) are pandemics that can continually spread in the air through micro-droplets or aerosols. However, the detection of samples in gaseous media is hampered by the requirement for trace amounts and low concentrations. Here, we develop a wearable bioelectronic mask device integrated with ion-gated transistors. Based on the sensitive gating effect of ion gels, our aptamer-functionalized transistors can measure trace-level liquid samples (0.3 μL) and even gaseous media samples at an ultra-low concentration (0.1 fg/mL). The ion-gated transistor with multi-channel analysis can respond to multiple targets simultaneously within as fast as 10 min, especially without sample pretreatment. Integrating a wireless internet of things system enables the wearable mask to achieve real-time and on-site detection of the surrounding air, providing an alert before infection. The wearable bioelectronic masks hold promise to serve as an early warning system to prevent outbreaks of respiratory infectious diseases.
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Affiliation(s)
- Bingfang Wang
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
| | - Deqi Yang
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
| | - Zhiqiang Chang
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
| | - Ru Zhang
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital affiliated to Tongji University, Shanghai 200120, China
| | - Jing Dai
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
| | - Yin Fang
- Research Center for Translational Medicine, Shanghai East Hospital affiliated to Tongji University, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai 200120, China
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital affiliated to Tongji University, Shanghai 200120, China
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16
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Cho J, Kim J, Kim Y. Development of a non-contact mobile screening center for infectious diseases: Effects of ventilation improvement on aerosol transmission prevention. SUSTAINABLE CITIES AND SOCIETY 2022; 87:104232. [PMID: 36212168 PMCID: PMC9526512 DOI: 10.1016/j.scs.2022.104232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/25/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Under the global landscape of the prolonged COVID-19 pandemic, the number of individuals who need to be tested for COVID-19 through screening centers is increasing. However, the risk of viral infection during the screening process remains significant. To limit cross-infection in screening centers, a non-contact mobile screening center (NCMSC) that uses negative pressure booths to improve ventilation and enable safe, fast, and convenient COVID-19 testing is developed. This study investigates aerosol transmission and ventilation control for eliminating cross-infection and for rapid virus removal from the indoor space using numerical analysis and experimental measurements. Computational fluid dynamics (CFD) simulations were used to evaluate the ventilation rate, pressure differential between spaces, and virus particle removal efficiency in NCMSC. We also characterized the airflow dynamics of NCMSC that is currently being piloted using particle image velocimetry (PIV). Moreover, design optimization was performed based on the air change rates and the ratio of supply air (SA) to exhaust air (EA). Three ventilation strategies for preventing viral transmission were tested. Based on the results of this study, standards for the installation and operation of a screening center for infectious diseases are proposed.
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Key Words
- ACH, Air Changes per Hour
- AR, Anteroom
- Aerosol transmission
- CFD, Computational Fluid Dynamics
- Computational fluid dynamics (CFD)
- EA, Eexhaust Air
- ER, Examination Room
- HCW, Health Care Worker
- Infectious disease
- NCMSC, Non-Contact Mobile Screening Center
- OA, Outdoor Air
- PIV, Particle Image Velocimetry
- Particle image velocimetry (PIV)
- SA, Supply Air
- SCB, Specimen Collection Booth
- Screening center
- TA, Transfer Air
- Ventilation strategy
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Affiliation(s)
- Jinkyun Cho
- Department of Building and Plant Engineering, Hanbat National University, Daejeon 34158, Republic of Korea
| | - Jinho Kim
- Department of Fire Protection, Safety and Facilities, Suwon Science College, Hwasung 18516, Republic of Korea
| | - Yundeok Kim
- Department of Architectural Engineering, Woosong University, Daejeon 34606, Republic of Korea
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17
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Argyropoulos CD, Skoulou V, Efthimiou G, Michopoulos AK. Airborne transmission of biological agents within the indoor built environment: a multidisciplinary review. AIR QUALITY, ATMOSPHERE, & HEALTH 2022; 16:477-533. [PMID: 36467894 PMCID: PMC9703444 DOI: 10.1007/s11869-022-01286-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
The nature and airborne dispersion of the underestimated biological agents, monitoring, analysis and transmission among the human occupants into building environment is a major challenge of today. Those agents play a crucial role in ensuring comfortable, healthy and risk-free conditions into indoor working and leaving spaces. It is known that ventilation systems influence strongly the transmission of indoor air pollutants, with scarce information although to have been reported for biological agents until 2019. The biological agents' source release and the trajectory of airborne transmission are both important in terms of optimising the design of the heating, ventilation and air conditioning systems of the future. In addition, modelling via computational fluid dynamics (CFD) will become a more valuable tool in foreseeing risks and tackle hazards when pollutants and biological agents released into closed spaces. Promising results on the prediction of their dispersion routes and concentration levels, as well as the selection of the appropriate ventilation strategy, provide crucial information on risk minimisation of the airborne transmission among humans. Under this context, the present multidisciplinary review considers four interrelated aspects of the dispersion of biological agents in closed spaces, (a) the nature and airborne transmission route of the examined agents, (b) the biological origin and health effects of the major microbial pathogens on the human respiratory system, (c) the role of heating, ventilation and air-conditioning systems in the airborne transmission and (d) the associated computer modelling approaches. This adopted methodology allows the discussion of the existing findings, on-going research, identification of the main research gaps and future directions from a multidisciplinary point of view which will be helpful for substantial innovations in the field.
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Affiliation(s)
| | - Vasiliki Skoulou
- B3 Challenge Group, Chemical Engineering, School of Engineering, University of Hull, Cottingham Road, Hull, HU6 7RX UK
| | - Georgios Efthimiou
- Centre for Biomedicine, Hull York Medical School, University of Hull, Cottingham Road, Hull, HU6 7RX UK
| | - Apostolos K. Michopoulos
- Energy & Environmental Design of Buildings Research Laboratory, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
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18
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James J, Byrne AMP, Goharriz H, Golding M, Cuesta JMA, Mollett BC, Shipley R, M McElhinney L, Fooks AR, Brookes SM. Infectious droplet exposure is an inefficient route for SARS-CoV-2 infection in the ferret model. J Gen Virol 2022; 103. [PMID: 36748502 DOI: 10.1099/jgv.0.001799] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in humans, has a wide host range, naturally infecting felids, canids, cervids, rodents and mustelids. Transmission of SARS-CoV-2 is universally accepted to occur via contact with contaminated secretions from the respiratory epithelium, either directly or indirectly. Transmission via droplet nuclei, generated from a cough or sneeze, has also been reported in several human and experimental animal scenarios. However, the role of droplet transmission at the human-animal interface remains to be fully elucidated. Here, the ferret infection model was used to investigate the routes of infection for the SARS-CoV-2 beta variant (B.1.351). Ferrets were exposed to droplets containing infectious SARS-CoV-2, ranging between 4 and 106 µm in diameter, simulating larger droplets produced by a cough from an infected person. Following exposure, viral RNA was detected on the fur of ferrets, and was deposited onto environmental surfaces, as well as the fur of ferrets placed in direct contact; SARS-CoV-2 remained infectious on the fur for at least 48 h. Low levels of viral RNA were detected in the nasal washes early post-exposure, yet none of the directly exposed, or direct-contact ferrets, became robustly infected or seroconverted to SARS-CoV-2. In comparison, ferrets intranasally inoculated with the SARS-CoV-2 beta variant became robustly infected, shedding viral RNA and infectious virus from the nasal cavity, with transmission to 75 % of naive ferrets placed in direct contact. These data suggest that larger infectious droplet nuclei and contaminated fur play minor roles in SARS-CoV-2 transmission among mustelids and potentially other companion animals.
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Affiliation(s)
- Joe James
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Alexander M P Byrne
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Hooman Goharriz
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Megan Golding
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Joan M A Cuesta
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Benjamin C Mollett
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Rebecca Shipley
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Lorraine M McElhinney
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Anthony R Fooks
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
| | - Sharon M Brookes
- Department of Virology, Animal and Plant Health Agency (APHA), Weybridge, Surrey, KT15 3NB, UK
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19
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Mahmood N, Bhatti S, Abbas SN, Shahid S, Nasir SB. The pncA gene mutations of Mycobacterium tuberculosis in multidrug-resistant tuberculosis. Biotechnol Appl Biochem 2022; 69:2195-2204. [PMID: 34731907 DOI: 10.1002/bab.2278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/22/2021] [Indexed: 01/28/2023]
Abstract
The pncA gene encodes pyrazinamidase enzyme which converts drug pyrazinamide to active form pyrazinoic acid, but mutations in this gene can prevent enzyme activity which leads to pyrazinamide resistance. The cross-sectional study was carried out during 2016-2017 for 12 months. The purpose of the study was to detect mutation at codon 12 and codon 85 in the pncA gene in local multidrug-resistant tuberculosis (MDR-TB) patients by developing a simple molecular test so that disease could be detected timely in the local population. DNA extracted from sputum-cultured samples from MDR-TB patients and subjected to semi-multiplex allele-specific PCR by using self-designed primers against the pncA gene. Among 75 samples, 53 samples were subjected to molecular analysis based on purified DNA quantity and quality. The primers produced 250 and 480 bp fragments, indicating the mutations at codon 12 (aspartate to alanine) and codon 85 (leucine to proline) respectively. MDR-TB was more common in the age group 21-40 years. Fifty-seven percent of samples (n = 30) were found positive for pncA mutations, whereas 43% of samples (n = 23) showed negative results. Thirteen percent of samples (n = 4) had mutations at codon 12 in which aspartate was converted to alanine, and they produced an amplified product of 480 bp. Eighty-seven percent of samples (n = 26) had mutations at codon 85 in which leucine was converted to proline and amplified product size was 250 bp. The mutations were simple nucleotide substitutions. The prevalence of mutations in which leucine was substituted by proline was higher than the mutations in which aspartate was substituted by alanine. A high prevalence of substitution mutation (CTG → CCG; leucine to proline) was detected in MDR-TB cases. Earlier detection of MDR-TB via an effective molecular diagnostic method can control the MDR tuberculosis spread in the population.
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Affiliation(s)
- Nasir Mahmood
- Department of Biochemistry and Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore, Pakistan
| | - Sadia Bhatti
- Department of Biology, Lahore Garrison University, Lahore, Pakistan
| | | | - Saman Shahid
- Department of Sciences and Humanities, National University of Computer & Emerging Sciences (NUCES), Foundation for Advancement of Science and Technology (FAST), Lahore, Pakistan
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20
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Prediction of respiratory droplets evolution for safer academic facilities planning amid COVID-19 and future pandemics: A numerical approach. JOURNAL OF BUILDING ENGINEERING 2022; 54:104593. [PMCID: PMC9107331 DOI: 10.1016/j.jobe.2022.104593] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 04/06/2022] [Accepted: 04/27/2022] [Indexed: 05/29/2023]
Abstract
Airborne dispersion of the novel SARS-CoV-2 through the droplets produced during expiratory activities is one of the main transmission mechanisms of this virus from one person to another. Understanding how these droplets spread when infected humans with COVID-19 or other airborne infectious diseases breathe, cough or sneeze is essential for improving prevention strategies in academic facilities. This work aims to assess the transport and fate of droplets in indoor environments using Computational Fluid Dynamics (CFD). This study employs unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations with the Euler-Lagrange approach to visualize the location of thousands of droplets released in a respiratory event and their size evolution. Furthermore, we assess the dispersion of coughing, sneezing, and breathing saliva droplets from an infected source in a classroom with air conditioning and multiple occupants. The results indicate that the suggested social distancing protocol is not enough to avoid the transmission of COVID-19 since small saliva droplets ( ≤ 12 μm) can travel in the streamwise direction up to 4 m when an infected person coughs and more than 7 m when sneezes. These droplets can reach those distances even when there is no airflow from the wind or ventilation systems. The number of airborne droplets in locations close to the respiratory system of a healthy person increases when the relative humidity of the indoor environment is low. This work sets an accurate, rapid, and validated numerical framework reproducible for various indoor environments integrating qualitative and quantitative data analysis of the droplet size evolution of respiratory events for a safer design of physical distancing standards and air cleaning technologies.
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21
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Niemiec T, Skowron K, Świderek W, Kwiecińska-Piróg J, Gryń G, Wójcik-Trechcińska U, Gajewska M, Zglińska K, Łozicki A, Koczoń P. Effect of radiant catalytic ionization on environmental conditions in rodent rooms and the haematological status of mice. BMC Vet Res 2022; 18:298. [PMID: 35922808 PMCID: PMC9347109 DOI: 10.1186/s12917-022-03402-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 07/20/2022] [Indexed: 11/26/2022] Open
Abstract
High stocking densities, closed animal houses, and elevated concentrations of bacteria, fungi, and the products of their activity, including ammonia and hydrogen sulphide, have adverse health effects. Active techniques used to reduce unfavourable environmental conditions, such as ventilation, sprinkling, bedding sorbents, and nutritional treatments, are not always sufficient to improve the animals’ living environment. The current paper aims to evaluate the effect of radiant catalytic ionization (RCI) on airborne microorganisms, cage microbiological status, gaseous ammonia concentrations, and the haematological status of mice in animal houses. After one week of operation of an RCI system, the number of airborne bacteria and fungi in the experimental room decreased in comparison to the first day of the experiment (p < 0.05 and p < 0.05 respectively), as did the concentrations of ammonia (p < 0.01) and dust. At the same time, the basic health parameters of the mice, determined in the blood, were very similar between the control and experimental room. RCI seems to be an ideal solution to ensure high hygiene standards in animal rooms and houses with limited use of disinfectants or antibiotic treatment of sick animals. An additional, environmental benefit is the limited amount of nitrogen released.
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Affiliation(s)
- Tomasz Niemiec
- Institute of Animal Sciences, Warsaw University of Animal Sciences, Warsaw, Poland
| | - Krzysztof Skowron
- Department of Microbiology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Collegium Medicum, Bydgoszcz, Poland
| | - Wiesław Świderek
- Institute of Animal Sciences, Warsaw University of Animal Sciences, Warsaw, Poland
| | - Joanna Kwiecińska-Piróg
- Department of Microbiology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Collegium Medicum, Bydgoszcz, Poland
| | - Grzegorz Gryń
- Plant Breeding and Acclimatization Institute - National Research Institute, Bydgoszcz, Poland
| | | | - Marta Gajewska
- Institute of Animal Sciences, Warsaw University of Animal Sciences, Warsaw, Poland
| | - Klara Zglińska
- Institute of Animal Sciences, Warsaw University of Animal Sciences, Warsaw, Poland.
| | - Andrzej Łozicki
- Institute of Animal Sciences, Warsaw University of Animal Sciences, Warsaw, Poland
| | - Piotr Koczoń
- Institute of Food Sciences, Warsaw University of Life Sciences, Warsaw, Poland
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22
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Li Y, Wu C, Cao G, Guan D, Zhan C. Transmission characteristics of respiratory droplets aerosol in indoor environment: an experimental study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2022; 32:1768-1779. [PMID: 33825604 DOI: 10.1080/09603123.2021.1910629] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
Transmission of droplets has been recognized as an important form of infection for the respiratory diseases. This study investigated the distribution of human respiratory droplets and assessed the effects of air change rate and generated velocity on droplet transmission using an active agent in an enclosed chamber (46 m3). Results revealed that the higher the air change rate was, the fewer viable droplets were detected in the range of <3.3 μm with ventilation; an increased air change rate can increase the attenuation of droplet aerosol. Without ventilation, the viable droplet size was observed to mainly distribute greater than 3.3 μm, which occupied up 87.5% of the total number. When the generated velocity was increased to 20 m/s, 29.38% of the viable droplets were detected at the position of 2.0 m. The findings are excepted to be useful for developing the technology of reducing droplet propagation and providing data verification for simulation research.
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Affiliation(s)
- Yanju Li
- School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China
| | - Chunbin Wu
- School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China
| | - Guoqing Cao
- Institute of Building Environment and Energy, China Academy of Building Research, Beijing, China
| | - Dexing Guan
- School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China
| | - Chaoguo Zhan
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin, China
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23
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Osman O, Madi M, Ntantis EL, Kabalan KY. Displacement ventilation to avoid COVID-19 transmission through offices. COMPUTATIONAL PARTICLE MECHANICS 2022; 10:355-368. [PMID: 35911865 PMCID: PMC9310363 DOI: 10.1007/s40571-022-00492-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/14/2022] [Accepted: 06/07/2022] [Indexed: 06/15/2023]
Abstract
Respiratory infections such as COVID-19 can be spread by respiratory droplets with a diameter larger than 5-10 μ m or by droplet nuclei with a diameter smaller than 5 μ m . Besides wearing masks, fresh air should be supplied frequently in closed rooms to avoid infections. Constructing and operating new isolation rooms require time, money, and maintenance cost, which are scarce in the current pandemic and in many communities. Displacement ventilation may be a feasible and secure option in temporary hospitals and other buildings to control the disease. This paper investigates using CFD simulations how displacement ventilation systems can deliver high air quality, and thermal comfort and minimize the risk of COVID-19 infection in enclosed spaces.
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Affiliation(s)
- Omar Osman
- Faculty of Engineering, Lebanese University, Hadath, Lebanon
| | - Mervat Madi
- Faculty of Engineering, Lebanese University, Hadath, Lebanon
- Higher Colleges of Technology, Abu Dhabi, UAE
| | | | - Karim Y. Kabalan
- Department of Electrical and Computer Engineering, American University of Beirut, Beirut, Lebanon
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24
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Niknahad A, Lakzian E, Saeedi A. Investigation of the effects of mechanical and underfloor heating systems on the COVID-19 viruses distribution. EUROPEAN PHYSICAL JOURNAL PLUS 2022; 137:798. [PMID: 35845823 PMCID: PMC9271557 DOI: 10.1140/epjp/s13360-022-02995-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Investigation of the spread of pollutants and especially pathogenic particles in the interior of today's buildings has become an integral part of the design of such buildings. When the Coronavirus is prevalent in the world, it is necessary to pay attention to the spread of the virus in the interior of residential apartments. In the present study, the Coronavirus particles emitted from the sneezing of a sick person in the bedroom of a residential apartment were tracked. Meanwhile, the degree of exposure of a mannequin that has been placed in the living room playing the role of a healthy person is examined. In this research, a segregated solution of steady-state flow and an unsteady particle solution have been separately used: a suitable, accurate, and optimal solution in particle studies. A comparison of the results shows that underfloor heating creates a healthier space around the healthy person's respiratory system, but instead, we will see more polluted areas around the sick person. According to the PRE results, the PRE value for a mechanical heating system is higher than a floor heating system. Therefore, it is recommended to use mechanical heating system in the apartments where the person with COVID-19 is hospitalized.
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Affiliation(s)
- Ali Niknahad
- Center of Computational Energy, Department of Mechanical Engineering, Hakim Sabzevari University, Sabzevar, Iran
| | - Esmail Lakzian
- Center of Computational Energy, Department of Mechanical Engineering, Hakim Sabzevari University, Sabzevar, Iran
- Peoples’ Friendship, University of Russia (RUDN University), 6 Miklukho‑Maklaya Street, 117198 Moscow, Russian Federation, Russia
| | - Arastoo Saeedi
- Head of Imam Ali Clinic, Oil Industry Health Organization, Shiraz, Iran
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Langalia A, Sinha N, Thakker V, Shah A, Shah J, Singh B. Saliva as a propitious diagnostic biofluid, biomarker, and bodies first line of defense against COVID-19: A review. J Family Med Prim Care 2022; 11:2292-2301. [PMID: 36119338 PMCID: PMC9480652 DOI: 10.4103/jfmpc.jfmpc_1567_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 12/13/2021] [Accepted: 12/20/2021] [Indexed: 11/05/2022] Open
Abstract
This review aims to recognize the role of saliva not just as a transmitting agent of COVID 19, but also comprehend its role in the diagnosis, and as a biomarker. A systematic literature search was performed in the PubMed database and eligible studies were included if they addressed the key issues i.e saliva as a diagnostic aid. As of January 10, 2021, a total of 309 articles across the PubMed database were identified of which 28 studies met the inclusion criteria. They were carefully examined for the type of study, sample size, parameters used, sample collection technique, and conclusions drawn. Diagnostic properties of saliva, the role of ACE 2 receptors, antibody formation ability, and antiviral characteristics were also explored. Comparisons among methods of sample collection like nasopharyngeal swabs and oropharyngeal swabs to saliva were also investigated. The observations and important deductions among the different studies were compared. Results indicated that saliva could be a reliable and financially viable option in both testing viral titers as well as marking for bio analytes due to its propitious specificity and sensitivity results reported in most of the studies. However, the inferences drawn from many of these studies should be interpreted with caution due to small sample sizes, inadequate detailing on the sample handling, laboratory processing, and rush in Corona-related publication. Scientific research with larger sample sizes, in diverse populations and age groups, at different phases of disease progression of COVID-19 are essential to reach any conclusion regarding its multi-facet use in the future.
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Affiliation(s)
- Akshay Langalia
- Department of Conservative Dentistry and Endodontics, AMC Dental College and Hospital, Ahmeddabad, Gujarat, India
| | - Nidhi Sinha
- Department of Conservative Dentistry and Endodontics, Pacific Dental College and Hospital, Udaipur, Rajasthan, India
| | - Viral Thakker
- Department of Periodontics, AMC Dental College and Hospital, Ahmeddabad, Gujarat, India
| | - Aarshvi Shah
- Department of Conservative Dentistry and Endodontics, AMC Dental College and Hospital, Ahmeddabad, Gujarat, India
| | - Jinali Shah
- Department of Conservative Dentistry and Endodontics, AMC Dental College and Hospital, Ahmeddabad, Gujarat, India
| | - Bijay Singh
- Department of Prosthodontics, Pacific Dental College and Hospital, Udaipur, Rajasthan, India
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26
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Ullah R, Ali H, Ali Z, Ahmad A, Khan S, Ahmed I. Evaluating the performance of multilayer perceptron algorithm for tuberculosis disease Raman data. Photodiagnosis Photodyn Ther 2022; 39:102924. [DOI: 10.1016/j.pdpdt.2022.102924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/14/2022] [Accepted: 05/20/2022] [Indexed: 11/24/2022]
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27
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Ability of Essential Oil Vapours to Reduce Numbers of Culturable Aerosolised Coronavirus, Bacteria and Fungi. Antibiotics (Basel) 2022; 11:antibiotics11030393. [PMID: 35326856 PMCID: PMC8944824 DOI: 10.3390/antibiotics11030393] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/04/2023] Open
Abstract
Transmission of pathogens present in the indoor air can occur through aerosols. This study evaluated the efficacy of an evaporated mix of essential oils to reduce the numbers of culturable aerosolized coronavirus, bacterium and fungus. The essential oil-containing gel was allowed to vaporize inside a glass chamber for 10 or 20 min. Aerosols of a surrogate of SARS-CoV-2, murine hepatitis coronavirus MHV-1, Escherichia coli or Aspergillus flavus spores were produced using a collision nebuliser and passed through the essential oil vapours, then collected on a six-stage Andersen sampler. The six-stages of the impact sampler capture aerosols in sizes ranging from 7 to 0.65 µm. The number of culturable microbes present in the aerosols collected in the different stages were enumerated and compared to the number of culturable microbes in control microbial aerosols that were not exposed to the evaporated essential oils. After 10 and 20 min evaporation, the essential oils reduced the numbers of culturable aerosolized coronavirus by 48% (log10 reduction = 0.3; p = 0.002 vs. control) and 53% (log10 reduction = 0.3; p = 0.001 vs. control), respectively. The essential oils vaporised for 10 min, reduced the number of viable E. coli by 51% (log10 reduction = 0.3; p = 0.032 vs. control). The Aspergillus flavus spores were mostly observed in the larger aerosols (7.00 µm to 2.10 µm) and the essential oils vaporised for 10 min reduced the number of viable spores by 72% (log10 reduction = 0.6; p = 0.008 vs. control). The vapours produced by a gel containing naturally occurring essential oils were able to significantly reduce the viable numbers of aerosolized coronavirus, bacteria and fungal spores. The antimicrobial gel containing the essential oils may be able to reduce aerosol transmission of microbes when used in domestic and workplace settings.
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28
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Rufino de Sousa N, Steponaviciute L, Margerie L, Nissen K, Kjellin M, Reinius B, Salaneck E, Udekwu KI, Rothfuchs AG. Detection and isolation of airborne SARS-CoV-2 in a hospital setting. INDOOR AIR 2022; 32:e13023. [PMID: 35347788 PMCID: PMC9111425 DOI: 10.1111/ina.13023] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/21/2022] [Accepted: 03/10/2022] [Indexed: 05/15/2023]
Abstract
Transmission mechanisms for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are incompletely understood. In particular, aerosol transmission remains unclear, with viral detection in air and demonstration of its infection potential being actively investigated. To this end, we employed a novel electrostatic collector to sample air from rooms occupied by COVID-19 patients in a major Swedish hospital. Electrostatic air sampling in conjunction with extraction-free, reverse-transcriptase polymerase chain reaction (hid-RT-PCR) enabled detection of SARS-CoV-2 in air from patient rooms (9/22; 41%) and adjoining anterooms (10/22; 45%). Detection with hid-RT-PCR was concomitant with viral RNA presence on the surface of exhaust ventilation channels in patients and anterooms more than 2 m from the COVID-19 patient. Importantly, it was possible to detect active SARS-CoV-2 particles from room air, with a total of 496 plaque-forming units (PFUs) being isolated, establishing the presence of infectious, airborne SARS-CoV-2 in rooms occupied by COVID-19 patients. Our results support circulation of SARS-CoV-2 via aerosols and urge the revision of existing infection control frameworks to include airborne transmission.
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Affiliation(s)
- Nuno Rufino de Sousa
- Department of Microbiology, Tumor and Cell Biology (MTC)Karolinska InstitutetStockholmSweden
| | - Laura Steponaviciute
- Department of Microbiology, Tumor and Cell Biology (MTC)Karolinska InstitutetStockholmSweden
| | - Lucille Margerie
- Department of Microbiology, Tumor and Cell Biology (MTC)Karolinska InstitutetStockholmSweden
| | - Karolina Nissen
- Department of Medical SciencesInfectious DiseasesUppsala UniversityUniversity Hospital UppsalaUppsalaSweden
| | - Midori Kjellin
- Department of Medical SciencesInfectious DiseasesUppsala UniversityUniversity Hospital UppsalaUppsalaSweden
| | - Björn Reinius
- Department of Medical Biochemistry and Biophysics (MBB)Karolinska InstitutetStockholmSweden
| | - Erik Salaneck
- Department of Medical SciencesInfectious DiseasesUppsala UniversityUniversity Hospital UppsalaUppsalaSweden
| | - Klas I. Udekwu
- Department of Aquatic Sciences and AssessmentSwedish University of Agricultural SciencesUppsalaSweden
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29
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Green WD, Ferguson NM, Cori A. Inferring the reproduction number using the renewal equation in heterogeneous epidemics. J R Soc Interface 2022; 19:20210429. [PMID: 35350879 PMCID: PMC8965414 DOI: 10.1098/rsif.2021.0429] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 01/28/2022] [Indexed: 12/30/2022] Open
Abstract
Real-time estimation of the reproduction number has become the focus of modelling groups around the world as the SARS-CoV-2 pandemic unfolds. One of the most widely adopted means of inference of the reproduction number is via the renewal equation, which uses the incidence of infection and the generation time distribution. In this paper, we derive a multi-type equivalent to the renewal equation to estimate a reproduction number which accounts for heterogeneity in transmissibility including through asymptomatic transmission, symptomatic isolation and vaccination. We demonstrate how use of the renewal equation that misses these heterogeneities can result in biased estimates of the reproduction number. While the bias is small with symptomatic isolation, it can be much larger with asymptomatic transmission or transmission from vaccinated individuals if these groups exhibit substantially different generation time distributions to unvaccinated symptomatic transmitters, whose generation time distribution is often well defined. The bias in estimate becomes larger with greater population size or transmissibility of the poorly characterized group. We apply our methodology to Ebola in West Africa in 2014 and the SARS-CoV-2 in the UK in 2020-2021.
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Affiliation(s)
- William D. Green
- Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Neil M. Ferguson
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
- Abdul Latif Jameel Institute for Disease and Emergency Analytics, Imperial College London, London, UK
| | - Anne Cori
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
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30
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Cline C, Bell TM, Facemire P, Zeng X, Briese T, Lipkin WI, Shamblin JD, Esham HL, Donnelly GC, Johnson JC, Hensley LE, Honko AN, Johnston SC. Detailed analysis of the pathologic hallmarks of Nipah virus (Malaysia) disease in the African green monkey infected by the intratracheal route. PLoS One 2022; 17:e0263834. [PMID: 35143571 PMCID: PMC8830707 DOI: 10.1371/journal.pone.0263834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 01/27/2022] [Indexed: 11/18/2022] Open
Abstract
Disease associated with Nipah virus infection causes a devastating and often fatal spectrum of syndromes predominated by both respiratory and neurologic conditions. Additionally, neurologic sequelae may manifest months to years later after virus exposure or apparent recovery. In the two decades since this disease emerged, much work has been completed in an attempt to understand the pathogenesis and facilitate development of medical countermeasures. Here we provide detailed organ system-specific pathologic findings following exposure of four African green monkeys to 2.41×105 pfu of the Malaysian strain of Nipah virus. Our results further substantiate the African green monkey as a model of human Nipah virus disease, by demonstrating both the respiratory and neurologic components of disease. Additionally, we demonstrate that a chronic phase of disease exists in this model, that may provide an important opportunity to study the enigmatic late onset and relapse encephalitis as it is described in human disease.
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Affiliation(s)
- Curtis Cline
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Todd M. Bell
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Paul Facemire
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Xiankun Zeng
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Thomas Briese
- Center for Infection and Immunity, Columbia University Mailman School of Public Health, New York, New York, United States of America
| | - W. Ian Lipkin
- Center for Infection and Immunity, Columbia University Mailman School of Public Health, New York, New York, United States of America
| | - Joshua D. Shamblin
- Veterinary Medicine Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Heather L. Esham
- Veterinary Medicine Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Ginger C. Donnelly
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Joshua C. Johnson
- Infectious Disease Research Portfolio, Strategy & Operations, Moderna, Boston, Massachusetts, United States of America
| | - Lisa E. Hensley
- Office of the Chief Scientist, National Institute of Allergy and Infectious Disease Integrated Research Facility, Fort Detrick, Maryland, United States of America
| | - Anna N. Honko
- Nonclinical Studies Unit, Boston University School of Medicine National Emerging Infectious Diseases Laboratories, Boston, Massachusetts, United States of America
| | - Sara C. Johnston
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
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31
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Angel DM, Gao D, DeLay K, Lin EZ, Eldred J, Arnold W, Santiago R, Redlich C, Martinello RA, Sherman JD, Peccia J, Godri Pollitt KJ. Development and Application of a Polydimethylsiloxane-Based Passive Air Sampler to Assess Personal Exposure to SARS-CoV-2. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2022; 9:153-159. [PMID: 37566382 PMCID: PMC8768000 DOI: 10.1021/acs.estlett.1c00877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 05/12/2023]
Abstract
Exhaled respiratory droplets and aerosols can carry infectious viruses and are an important mode of transmission for COVID-19. Recent studies have been successful in detecting airborne SARS-CoV-2 RNA in indoor settings using active sampling methods. The cost, size, and maintenance of these samplers, however, limit their long-term monitoring ability in high-risk transmission areas. As an alternative, passive samplers can be small, lightweight, and inexpensive and do not require electrical power or maintenance for continual operation. Integration of passive samplers into wearable designs can be used to better understand personal exposure to the respiratory virus. This study evaluated the use of a polydimethylsiloxane (PDMS)-based passive sampler to assess personal exposure to aerosol and droplet SARS-CoV-2. The rate of uptake of virus-laden aerosol on PDMS was determined in lab-based rotating drum experiments to estimate time-weighted averaged airborne viral concentrations from passive sampler viral loading. The passive sampler was then embedded in a wearable clip design and distributed to community members across Connecticut to surveil personal SARS-CoV-2 exposure. The virus was detected on clips worn by five of the 62 participants (8%) with personal exposure ranging from 4 to 112 copies of SARS-CoV-2 RNA/m3, predominantly in indoor restaurant settings. Our findings demonstrate that PDMS-based passive samplers may serve as a useful exposure assessment tool for airborne viral exposure in real-world high-risk settings and provide avenues for early detection of potential cases and guidance on site-specific infection control protocols that preempt community transmission.
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Affiliation(s)
- Darryl M. Angel
- Department of Chemical and Environmental Engineering,
Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06520, United
States
| | - Dong Gao
- Department of Environmental Health Sciences,
Yale School of Public Health, New Haven, Connecticut 06520,
United States
| | - Kayley DeLay
- Department of Chemical and Environmental Engineering,
Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06520, United
States
- Department of Environmental Health Sciences,
Yale School of Public Health, New Haven, Connecticut 06520,
United States
| | - Elizabeth Z. Lin
- Department of Environmental Health Sciences,
Yale School of Public Health, New Haven, Connecticut 06520,
United States
| | - Jacob Eldred
- Department of Mechanical Engineering and Materials
Science, Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06511, United
States
| | - Wyatt Arnold
- Department of Chemical and Environmental Engineering,
Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06520, United
States
| | - Romero Santiago
- Department of Internal Medicine, Yale
School of Medicine, New Haven, Connecticut 06510, United
States
| | - Carrie Redlich
- Department of Internal Medicine, Yale
School of Medicine, New Haven, Connecticut 06510, United
States
| | - Richard A. Martinello
- Department of Internal Medicine, Yale
School of Medicine, New Haven, Connecticut 06510, United
States
- Department of Infection Prevention, Yale
New Haven Health System, New Haven, Connecticut 06510, United
States
- Department of Pediatrics, Yale School of
Medicine, New Haven, Connecticut 06510, United
States
| | - Jodi D. Sherman
- Department of Environmental Health Sciences,
Yale School of Public Health, New Haven, Connecticut 06520,
United States
- Department of Anesthesiology, Yale School of
Medicine, New Haven, Connecticut 06510, United
States
| | - Jordan Peccia
- Department of Chemical and Environmental Engineering,
Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06520, United
States
| | - Krystal J. Godri Pollitt
- Department of Chemical and Environmental Engineering,
Yale School of Engineering and Applied Science, Yale
University, New Haven, Connecticut 06520, United
States
- Department of Environmental Health Sciences,
Yale School of Public Health, New Haven, Connecticut 06520,
United States
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32
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Bunyasi EW, Middelkoop K, Koch A, Hoosen Z, Mulenga H, Luabeya AKK, Shenje J, Mendelsohn SC, Tameris M, Scriba TJ, Warner DF, Wood R, Andrews JR, Hatherill M. Molecular Detection of Airborne Mycobacterium tuberculosis in South African High Schools. Am J Respir Crit Care Med 2022; 205:350-356. [PMID: 34752730 PMCID: PMC8886998 DOI: 10.1164/rccm.202102-0405oc] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Rationale: South African adolescents carry a high tuberculosis disease burden. It is not known if schools are high-risk settings for Mycobacterium tuberculosis (MTB) transmission. Objectives: To detect airborne MTB genomic DNA in classrooms. Methods: We studied 72 classrooms occupied by 2,262 students in two South African schools. High-volume air filtration was performed for median 40 (interquartile range [IQR], 35-54) minutes and assayed by droplet digital PCR (ddPCR)-targeting MTB region of difference 9 (RD9), with concurrent CO2 concentration measurement. Classroom data were benchmarked against public health clinics. Students who consented to individual tuberculosis screening completed a questionnaire and sputum collection (Xpert MTB/RIF Ultra) if symptom positive. Poisson statistics were used for MTB RD9 copy quantification. Measurements and Main Results: ddPCR assays were positive in 13/72 (18.1%) classrooms and 4/39 (10.3%) clinic measurements (P = 0.276). Median ambient CO2 concentration was 886 (IQR, 747-1223) ppm in classrooms versus 490 (IQR, 405-587) ppm in clinics (P < 0.001). Average airborne concentration of MTB RD9 was 3.61 copies per 180,000 liters in classrooms versus 1.74 copies per 180,000 liters in clinics (P = 0.280). Across all classrooms, the average risk of an occupant inhaling one MTB RD9 copy was estimated as 0.71% during one standard lesson of 35 minutes. Among 1,836/2,262 (81.2%) students who consented to screening, 21/90 (23.3%) symptomatic students produced a sputum sample, of which one was Xpert MTB/RIF Ultra positive. Conclusions: Airborne MTB genomic DNA was detected frequently in high school classrooms. Instantaneous risk of classroom exposure was similar to the risk in public health clinics.
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Affiliation(s)
- Erick W. Bunyasi
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | | | - Anastasia Koch
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Institute of Infectious Disease and Molecular Medicine, and
| | | | - Humphrey Mulenga
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Angelique K. K. Luabeya
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Justin Shenje
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Simon C. Mendelsohn
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Michele Tameris
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Thomas J. Scriba
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
| | - Digby F. Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Institute of Infectious Disease and Molecular Medicine, and,Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), University of Cape Town, Cape Town, South Africa; and
| | | | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California
| | - Mark Hatherill
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine,,Department of Pathology
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33
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Lim JH, Nam SH, Kim J, Kim NH, Park GS, Maeng JS, Yook SJ. Development of Three-Stage Bioaerosol Sampler for Size-Selective Sampling. J Biomech Eng 2022; 144:1131184. [PMID: 35013744 DOI: 10.1115/1.4053504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Indexed: 11/08/2022]
Abstract
In this study, a three-stage bioaerosol sampler with a sampling flow rate of 170 L/min was designed and fabricated for sampling the bioaerosols released during human breathing and coughing, and its performance was evaluated. The sampler was constructed using a cyclone separator with a cutoff size of 2.5 µm as a preseparator, a multi-nozzle virtual impactor with a cutoff size of 0.34 µm as an aerosol concentrator, and a BioSampler, which is a commercial product, for collecting bioaerosols in a collection fluid. The collection efficiency of the sampler was evaluated through simulations and experiments. Only particles with sizes of 0.1-4 µm were selectively collected in the collection fluid. Bacteriophage bioaerosols were sampled using the developed sampler and ACD-200 Bobcat sampler, which is a commercial product. The amounts of collected bacteriophages were compared using the polymerase chain reaction (PCR) technique. The sampling performance of the developed sampler was similar to that of the ACD-200 Bobcat sampler. Moreover, the developed sampler showed its ability to sample bioaerosols of a specific size-range and collect them directly in a collection fluid for the PCR analysis. Therefore, the developed sampler is expected to be useful for indoor environmental monitoring by effectively sampling the bioaerosols released indoors during human breathing and coughing.
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Affiliation(s)
- Jun-Hyung Lim
- School of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Sang Hwan Nam
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 34114, Republic of Korea
| | - Jongwoo Kim
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 34114, Republic of Korea
| | - Nam Hoon Kim
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 34114, Republic of Korea
| | - Gun-Soo Park
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 34114, Republic of Korea; Research Group of Food Processing, Korea Food Research Institute, Wanju, Jeonbuk 55365, Republic of Korea
| | - Jin-Soo Maeng
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 34114, Republic of Korea; Research Group of Food Processing, Korea Food Research Institute, Wanju, Jeonbuk 55365, Republic of Korea
| | - Se-Jin Yook
- School of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
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34
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Babando J, Quesnel DA, Woodmass K, Lomness A, Graham JR. Responding to pandemics and other disease outbreaks in homeless populations: A review of the literature and content analysis. HEALTH & SOCIAL CARE IN THE COMMUNITY 2022; 30:11-26. [PMID: 33825271 PMCID: PMC8251050 DOI: 10.1111/hsc.13380] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/15/2021] [Accepted: 03/17/2021] [Indexed: 05/06/2023]
Abstract
Considering the recent COVID-19 pandemic, we recognised a lack of synthesis amongst the available literature pertaining to the intersections of homelessness and pandemic response and planning. Therefore, the purpose of this review was to identify relevant peer-reviewed literature in this area to thematically produce evidence-based recommendations that would inform community planning and response amongst homeless populations. Although this review is inspired by the COVID-19 pandemic, our intention was to produce relevant recommendations to for all current and future outbreaks and pandemics more generally. Our search criteria focused on pandemics and rapid-spread illnesses such as contagious respiratory diseases with contact spread and with an emphasis on individuals experiencing homelessness. Content analysis methods were followed to extract and thematically synthesise key information amongst the 223 articles that matched our search criteria between the years of 1984 and 2020. Two reviewers were assigned to the screening process and used Covidence and undertook two rounds of discussion to identify and finalise themes for extraction. This review illustrates that the current breadth of academic literature on homeless populations has thus far focused on tuberculosis (TB) rather than diseases that are more recent and closely related to COVID-19-such as Severe Acute Respiratory Syndrome (SARS) or H1N1. Our thematic content analysis revealed six themes that offer tangible and scalable recommendations which include (1) education and outreach, (2) adapting structure of services, (3) screening and contract tracing, (4) transmission and prevention strategies, (5) shelter protocols and (6) treatment, adherence and vaccination. The breadth and depth of reviews such as these are dependent on the quantity and quality of the available literature. Therefore, the limited existing literature outside of tuberculosis specific to homelessness in this review illustrates a need for more academic research into the intersections of pandemics and homelessness-particularly for evaluations of response and planning. Nonetheless, this review offers timely considerations for pandemic response and planning amongst homeless populations during the current COVID-19 pandemic and can facilitate future research in this area.
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Affiliation(s)
- Jordan Babando
- School of Social WorkUniversity of British Columbia‐Okanagan CampusKelownaBritish ColumbiaCanada
| | - Danika A. Quesnel
- School of Social WorkUniversity of British Columbia‐Okanagan CampusKelownaBritish ColumbiaCanada
| | - Kyler Woodmass
- School of Social WorkUniversity of British Columbia‐Okanagan CampusKelownaBritish ColumbiaCanada
| | - Arielle Lomness
- Okanagan LibraryUniversity of British Columbia‐Okanagan CampusKelownaBritish ColumbiaCanada
| | - John R. Graham
- School of Social WorkUniversity of British Columbia‐Okanagan CampusKelownaBritish ColumbiaCanada
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Al-Rubaey NF, Hussain H, Ibraheem N, Radhi M, Hindi NK, AL-Jubori RK. A review of airborne contaminated microorganisms associated with human diseases. MEDICAL JOURNAL OF BABYLON 2022. [DOI: 10.4103/mjbl.mjbl_20_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Optimal control analysis of a COVID-19 and tuberculosis co-dynamics model. INFORMATICS IN MEDICINE UNLOCKED 2022; 28:100849. [PMID: 35071729 PMCID: PMC8759807 DOI: 10.1016/j.imu.2022.100849] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/02/2022] [Accepted: 01/02/2022] [Indexed: 01/08/2023] Open
Abstract
Tuberculosis and COVID-19 are among the diseases with major global public health concern and great socio-economic impact. Co-infection of these two diseases is inevitable due to their geographical overlap, a potential double blow as their clinical similarities could hamper strategies to mitigate their spread and transmission dynamics. To theoretically investigate the impact of control measures on their long-term dynamics, we formulate and analyze a mathematical model for the co-infection of COVID-19 and tuberculosis. Basic properties of the tuberculosis only and COVID-19 only sub-models are investigated as well as bifurcation analysis (possibility of the co-existence of the disease-free and endemic equilibria). The disease-free and endemic equilibria are globally asymptotically stable. The model is extended into an optimal control system by incorporating five control measures. These are: tuberculosis awareness campaign, prevention against COVID-19 (e.g., face mask, physical distancing), control against co-infection, tuberculosis and COVID-19 treatment. Five strategies which are combinations of the control measures are investigated. Strategy B which focuses on COVID-19 prevention, treatment and control of co-infection yields a better outcome in terms of the number of COVID-19 cases prevented at a lower percentage of the total cost of this strategy.
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Effectiveness of barrier devices, high-volume evacuators, and extraoral suction devices on reducing dental aerosols for the dental operator: A pilot study. J Am Dent Assoc 2021; 153:309-318.e1. [PMID: 34952682 PMCID: PMC8885443 DOI: 10.1016/j.adaj.2021.08.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 07/30/2021] [Accepted: 08/29/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND The COVID-19 pandemic has increased the importance of minimizing exposure to aerosols generated during dental procedures. The authors' objective was to measure the aerosolized particles in the breathing zone of operators using several facial protection and filtration methods. METHODS Twenty-one dentists performed maxillary anterior incisor veneer preparations using a microscope and drape and loupes with or without a face shield. In each test condition, the following 3 levels of filtration were tested: no filtration, a high-volume evacuator [HVE], and an HVE with an extraoral suction device. Measurements were made using a mass monitor attached to the operator's chest with inlet within 10 inches of the operator's face. RESULTS The authors found that the microscope and drape provided the lowest levels of aerosolized particles compared with loupes with or without a face shield (P < .001). There was no detectable difference in the concentration of particles between operators wearing a face shield and wearing loupes alone (P = .47). The particles in each test condition were lowered when an HVE was used (P < .001) and further lowered with an extraoral suction device. CONCLUSIONS The findings of this study suggest that the use of a surgical microscope and bag barrier drape, HVE, and extraoral suction device result in the lowest concentration of aerosolized particles. The face shield did not appear to offer any protection from aerosolized particles. HVE and extraoral suction were effective in decreasing aerosols regardless of the type of facial protection used. PRACTICAL IMPLICATIONS Dentists can reduce exposure to aerosols with a drape, HVE, and extraoral suction.
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Abstract
Since the outbreak in late December 2019, the coronavirus disease 2019 (COVID-19) pandemic has spread across the globe, causing great damage to human life and property. A lot of researchers around the world have devoted themselves to the study of its origin, pathogenic mechanism, and transmission route, and this article gives a summary. First, both humans and animals can act as the host of coronavirus. In indoor environments, the virus may exist in aerosols, droplets, saliva, etc., from the nose and mouth connected to the respiratory system, as well as feces, urine, etc., from the digestive and urinary systems. In addition, other substances, such as breast milk, eye feces, and blood, released from the host can carry viruses. The virus transmitted indoors is affected by indoor machinery, natural forces, and human activities, and spreads in different distances. Second, the virus spreads outdoors through three kinds of media: solid, liquid, and gas, and is affected by their survival time, the temperature, and humidity in the environment.
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Büchner F, Hoffman M, Dobermann UH, Edel B, Lehmann T, Kipp F. Do closed waste containers lead to less air contamination than opened? A clinical case study at Jena University Hospital, Germany. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 136:11-17. [PMID: 34634566 DOI: 10.1016/j.wasman.2021.09.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 09/13/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
Nosocomial infections are a growing challenge at hospitals. This clinical study aimed to investigate the influence of waste container construction ((open (O), closed (C), and hands-free opening (HF)) on microbial air contamination in a hospital setting. The results are intended to help develop guidelines for waste containers for the collection of non-infectious waste at hospitals and medical facilities. The clinical experiment was conducted at the University Hospital Jena, Germany. Air Impactor samples were performed and microbiologically evaluated for bacteria and fungi both quantitatively and qualitatively. The results were statistically determined using generalized estimating equations. Quantitatively, the lowest bacterial counts in ambient air were found around closed waste containers (114.74 CFU/m3) in comparison to HF (129.28 CFU/m3) and O (126.28 CFU/m3). For fungi, the surrounding air of C (2.08 CFU/m3) and HF (1.97 CFU/m3) waste containers showed a lower impact of fungal air contamination than for O (2.32 CFU/m3). Overall, it was shown that C are more preferable to HF and O waste containers from the point of view of microbial air contamination at hospitals.
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Affiliation(s)
- Franziskus Büchner
- Institute for Infectious Diseases and Infection Control, Jena University Hospital, Am Klinikum 1, D-07747 Jena, Germany.
| | - Marc Hoffman
- Integrative Health and Security Management Center, Staff Section Environmental Protection, Jena University Hospital, Bachstraße 18, D-07743 Jena, Germany
| | - Ute-Helke Dobermann
- Institute for Infectious Diseases and Infection Control, Jena University Hospital, Am Klinikum 1, D-07747 Jena, Germany
| | - Birgit Edel
- Institute of Medical Microbiology, Jena University Hospital, Am Klinikum 1, D-07747 Jena, Germany
| | - Thomas Lehmann
- Institute of Medical Statistics, Computer and Data Sciences, Jena University Hospital, Bachstraße 18, D-07743 Jena, Germany
| | - Frank Kipp
- Institute for Infectious Diseases and Infection Control, Jena University Hospital, Am Klinikum 1, D-07747 Jena, Germany
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Hydroxypropyl Methylcellulose-Based Nasal Sprays Effectively Inhibit In Vitro SARS-CoV-2 Infection and Spread. Viruses 2021; 13:v13122345. [PMID: 34960612 PMCID: PMC8705245 DOI: 10.3390/v13122345] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/11/2021] [Accepted: 11/18/2021] [Indexed: 11/26/2022] Open
Abstract
The ongoing coronavirus disease (COVID-19) pandemic has required a variety of non-medical interventions to limit the transmission of the causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). One such option is over-the-counter nasal sprays that aim to block virus entry and transmission within the nasal cavity. In this study, we assessed the ability of three hydroxypropyl methylcellulose (HPMC)-based powder nasal sprays, produced by Nasaleze, to inhibit SARS-CoV-2 infection and release in vitro. Upon application, the HPMC powder forms a gel-like matrix within the nasal cavity—a process we recapitulated in cell culture. We found that virus release from cells previously infected with SARS-CoV-2 was inhibited by the gel matrix product in a dose-dependent manner, with virus levels reduced by >99.99% over a 72 h period at a dose of 6.4 mg/3.5 cm2. We also show that the pre-treatment of cells with product inhibited SARS-CoV-2 infection, independent of the virus variant. The primary mechanism of action appears to be via the formation of a physical, passive barrier. However, the addition of wild garlic provided additional direct antiviral properties in some formulations. We conclude that HPMC-based nasal sprays may offer an additional component to strategies to limit the spread of respiratory viruses, including SARS-CoV-2.
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Rencken GK, Rutherford EK, Ghanta N, Kongoletos J, Glicksman L. Patterns of SARS-CoV-2 aerosol spread in typical classrooms. BUILDING AND ENVIRONMENT 2021; 204:108167. [PMID: 34305270 PMCID: PMC8294611 DOI: 10.1016/j.buildenv.2021.108167] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 07/17/2021] [Indexed: 06/13/2023]
Abstract
Although current industry guidelines to control the spread of aerosols such as SARS-CoV-2 (COVID-19) have adopted a six-foot (~1.8 m) spacing between individuals indoors, recent evidence suggests that longer range spread is also responsible for infections in public spaces. The vehicle for long-range spread is smaller (<5 μm) droplets or particles, termed bio-aerosols, or aerosols for short, which have a large surface area to volume ratio such that aerodynamic drag is much larger than gravity forces. The aerosols remain suspended in air for extended time periods, and they essentially move with air currents. Prediction of the danger to occupants in a closed room when exposed to an infected individual requires knowledge of the period of exposure and the concentration level of aerosols in the breathing zone of an occupant. To obtain an estimate of the concentration level, a common assumption is well-mixed conditions within an interior space. This is obtained from a mass balance between the level of aerosol produced by an infected individual along with the airflow rate into and out of the entire space. In this work, we use computational fluid dynamics, compared with experimental results in several cases, to explore the aerosol concentration distribution in a typical classroom for several common conditions and compare these results to the well-mixed assumption. We use a tracer gas to approximately simulate the flow and dispersion of the aerosol-air mixture. The two ventilation systems examined, ceiling diffusers and open windows, yield average concentrations at occupant breathing level 50 % greater than the well mixed case, and some scenarios yield concentrations that are 150 % greater than the well mixed concentration at specific breathing-level locations. Of particular concern are two conditions: horizontal air flow from an open window in line with a row of seating and, second, an infected individual seated near a sealed cold window. For the former, conditions are improved if a baffle is placed inside the open window to direct the air toward the floor, creating a condition similar to displacement ventilation. In the latter, the cold air flowing down along the cold window recirculates aerosols back into the breathing zone. Adding window covers or a portable heater below the window surface will moderate this condition.
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Bahadur GK, Jodheea-Jutton A, Mowlabaccus WB, Callychurn D, Ramasamy S. Design and Development of Isolating Pods to Prevent the Spread of Coronavirus or Other Viruses for Hospital and Domestic Purposes. HERD-HEALTH ENVIRONMENTS RESEARCH & DESIGN JOURNAL 2021; 15:39-54. [PMID: 34636694 DOI: 10.1177/19375867211045398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES This project investigated into the design and construction of an isolation pod to keep infected people in quarantine, thus avoiding the spread of viruses such as the COVID-19. This product was made to be used in hospitals and at homes. BACKGROUND Mauritius is among the few countries, which has not had any cases of COVID-19 since for since May 2020 for a period of 150 days. It has opened its borders since October 2020, and since Mauritius being a small country, the spread of any type of virus can be imminent if not controlled properly. In case there is another spread of the COVID-19 in Mauritius, then the isolation pod could be used to keep infected people in quarantine. The aims of the study were to develop a prototype of an isolation cubicle that is collapsible and can be easily erected at homes or in hospitals, whenever the need arises. METHODS A prototype of the pod was made with metal bars welded together and tarpaulin materials were sewn together. A HEPA Fan Extractor was fitted inside the pod to allow the air to circulate. RESULTS the tests carried out the pod could easily be assembled, transported and stored for further usage. From the volunteers' feedback, it was found that the pod was comfortable, spacious, and practical. The air monitoring tests carried on the carbon dioxide, temperature, and relative humidity were within the acceptable ranges.
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Zarei M, Rahimi K, Hassanzadeh K, Abdi M, Hosseini V, Fathi A, Kakaei K. From the environment to the cells: An overview on pivotal factors which affect spreading and infection in COVID-19 pandemic. ENVIRONMENTAL RESEARCH 2021; 201:111555. [PMID: 34197816 PMCID: PMC8236413 DOI: 10.1016/j.envres.2021.111555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 05/24/2021] [Accepted: 06/16/2021] [Indexed: 05/06/2023]
Abstract
Several factors ranging from environmental risks to the genetics of the virus and that of the hosts, affect the spread of COVID-19. The impact of physicochemical variables on virus vitality and spread should be taken into account in experimental and clinical studies. Another avenue to explore is the effect of diet and its interaction with the immune system on SARS-CoV-2 infection and mortality rate. Past year have witnessed extensive studies on virus and pathophysiology of the COVID-19 disease and the cellular mechanisms of virus spreading. However, our knowledge has not reached a level where we plan an efficient therapeutic approach to prevent the virus entry to the cells or decreasing the spreading and morbidity in severe cases of disease. The risk of infection directly correlates with the control of virus spreading via droplets and aerosol transmission, as well as patient immune system response. A key goal in virus restriction and transmission rate is to understand the physicochemical structure of aerosol and droplet formation, and the parameters that affect the droplet-borne and airborne in different environmental conditions. The lifetime of droplets on different surfaces is described based on the contact angle. Hereby, we recommend regular use of high-quality face masks in high temperature and low humidity conditions. However, in humid and cold weather conditions, wearing gloves and frequently hand washing, gain a higher priority. Additionally, social distancing rules should be respected in all aforementioned conditions. We will also discuss different routes of SARS-CoV-2 entry into the cells and how multiple genetic factors play a role in the spread of the virus. Given the role of environmental and nutritional factors, we discuss and recommend some strategies to prevent the disease and protect the population against COVID-19. Since an effective vaccine can prevent the transmission of communicable diseases and abolish pandemics, we added a brief review of candidate SARS-CoV-2 vaccines.
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Affiliation(s)
- Mohammad Zarei
- Department of Food Science and Technology, School of Industrial Technology, Faculty of Applied Sciences, Universiti Teknologi MARA, 40450, Shah Alam, Selangor, Malaysia
| | - Karim Rahimi
- Department of Molecular Biology and Genetics, Gene Expression and Gene Medicine, Aarhus University, Aarhus, Denmark
| | - Kambiz Hassanzadeh
- Laboratory of Neuronal Cell Signaling, EBRI Rita Levi-Montalcini Foundation, Rome, 00161, Italy; Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, 67100, L'Aquila, Italy
| | - Mohammad Abdi
- Department of Clinical Biochemistry, Faculty of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Vahedeh Hosseini
- Department of Molecular Medicine and Genetics, Faculty of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Ali Fathi
- FUJIFILM Cellular Dynamics, Inc., Madison, WI, USA.
| | - Karim Kakaei
- Department of Chemistry, Faculty of Science, University of Maragheh, Maragheh, Iran.
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The Role of HVAC Design and Windows on the Indoor Airflow Pattern and ACH. SUSTAINABILITY 2021. [DOI: 10.3390/su13147931] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The purpose of heating, ventilation, and air conditioning (HVAC) systems are to create optimum thermal comfort and appropriate indoor air quality (IAQ) for occupants. Air ventilation systems can significantly affect the health risk in indoor environments, especially those by contaminated aerosols. Therefore, the main goal of the study is to analyze the indoor airflow patterns in the heating, ventilation, and air conditioning (HVAC) systems and the impact of outlets/windows. The other goal of this study is to simulate the trajectory of the aerosols from a human sneeze, investigate the impact of opening windows on the number of air changes per hour (ACH) and exhibit the role of dead zones with poor ventilation. The final goal is to show the application of computational fluid dynamics (CFD) simulation in improving the HVAC design, such as outlet locations or airflow rate, in addition to the placement of occupants. In this regard, an extensive literature review has been combined with the CFD method to analyze the indoor airflow patterns, ACH, and the role of windows. The airflow pattern analysis shows the critical impact of inflow/outflow and windows. The results show that the CFD model simulation could exhibit optimal placement and safer locations for the occupants to decrease the health risk. The results of the discrete phase simulation determined that the actual ACH could be different from the theoretical ACH as the short circuit and dead zones affect the ACH.
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Effects of Natural Ventilation and Saliva Standard Ejectors during the COVID-19 Pandemic: A Quantitative Analysis of Aerosol Produced during Dental Procedures. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147472. [PMID: 34299930 PMCID: PMC8308059 DOI: 10.3390/ijerph18147472] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 12/19/2022]
Abstract
The novel Coronavirus Disease 2019 (COVID-19) pandemic has renewed attention to aerosol-generating procedures (AGPs). Dental-care workers are at high risk of contamination by SARS-CoV-2. The aim of this study was to evaluate the efficacy of standard saliva ejectors and natural ventilation in reducing particulate matter (PM) concentration during different routine dental procedures in the pandemic period. The DustTrak monitor was used to measure PM1, PM2.5, PM10, and breathable (<4 microns) total dust during 14 procedures performed with and without the presence of natural ventilation in a dental unit. Moreover, measurements were performed near the practitioners or near the standard saliva ejectors during the different procedures. In the latter condition, reduced levels of PM10 were recorded (82.40 ± 9.65 μg/m3 vs. 50.52 ± 0.23 μg/m3). Moreover, higher levels of PM (53.95 ± 2.29 μg/m3 vs. 27.85 ± 0.14 μg/m3) were produced when the dental unit's windows were open. At the same time, the total level of PM were higher during scaling than during other procedures (data suggest not to adopt natural ventilation-both window and door opened-during dental procedures). It was also demonstrated that the use of standard saliva ejectors can considerably reduce the total released amount of PM10.
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Li F, Jiang H, Shen X, Yang W, Guo C, Wang Z, Xiao M, Cui L, Luo W, Kim BS, Chen Z, Huang AJW, Liu Q. Sneezing reflex is mediated by a peptidergic pathway from nose to brainstem. Cell 2021; 184:3762-3773.e10. [PMID: 34133943 PMCID: PMC8396370 DOI: 10.1016/j.cell.2021.05.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 04/05/2021] [Accepted: 05/12/2021] [Indexed: 12/24/2022]
Abstract
Sneezing is a vital respiratory reflex frequently associated with allergic rhinitis and viral respiratory infections. However, its neural circuit remains largely unknown. A sneeze-evoking region was discovered in both cat and human brainstems, corresponding anatomically to the central recipient zone of nasal sensory neurons. Therefore, we hypothesized that a neuronal population postsynaptic to nasal sensory neurons mediates sneezing in this region. By screening major presynaptic neurotransmitters/neuropeptides released by nasal sensory neurons, we found that neuromedin B (NMB) peptide is essential for signaling sneezing. Ablation of NMB-sensitive postsynaptic neurons in the sneeze-evoking region or deficiency in NMB receptor abolished the sneezing reflex. Remarkably, NMB-sensitive neurons further project to the caudal ventral respiratory group (cVRG). Chemical activation of NMB-sensitive neurons elicits action potentials in cVRG neurons and leads to sneezing behavior. Our study delineates a peptidergic pathway mediating sneezing, providing molecular insights into the sneezing reflex arc.
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Affiliation(s)
- Fengxian Li
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Haowu Jiang
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiaolei Shen
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Weishan Yang
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Changxiong Guo
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhiyao Wang
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Maolei Xiao
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lian Cui
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Wenqin Luo
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Brian S Kim
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA; Division of Dermatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhoufeng Chen
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA; Division of Dermatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Andrew J W Huang
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Qin Liu
- Department of Anesthesiology, Center for the Study of Itch and Sensory Disorders, and Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, USA; Division of Dermatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Zacharias N, Haag A, Brang-Lamprecht R, Gebel J, Essert SM, Kistemann T, Exner M, Mutters NT, Engelhart S. Air filtration as a tool for the reduction of viral aerosols. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 772:144956. [PMID: 33571771 DOI: 10.1016/j.scitotenv.2021.144956] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/02/2020] [Accepted: 12/31/2020] [Indexed: 06/12/2023]
Abstract
For testing the effectiveness of air purification devices in regard to the reduction of virus-containing aerosols, a test method involving test viruses has been lacking until now. The use of bacteriophages (phiX174 phages) is a method to test the efficiency of air purification devices under experimental conditions. Using air purifiers with a HEPA filter H14, a 4.6-6.1 Log reduction of test viruses can be achieved if bacteriophages are directly aerosolised into the air purifier, which corresponds to a reduction of 99.9974-99.9999%. Due to the complexity and individuality of air flow, an experimental approach was used in which all outside influences were minimised. The experimental setup was practical and chosen to project a scenario of direct transmission by an emitting source to a recipient. The experiments were performed with and without the air purifier at a distance of 0.75 m and 1.5 m each. Using the air purifier at a setting of 1000 m3/h, the concentration of the phiX174 phages in the air could be reduced by 2.86 Log (mean value). Nevertheless, the experiments without the air purifier showed a similar reduction rate of 2.61 Log (mean value) after 35 min. The concentration of phiX174 phages in the air could be additionally reduced up to 1 log step (maximum value) by the use of the air purifier in comparison to the experiments without. Distance was shown to be an important factor for risk reduction.
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Affiliation(s)
- Nicole Zacharias
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany.
| | - Alexandra Haag
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Regina Brang-Lamprecht
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Jürgen Gebel
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Sarah M Essert
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Thomas Kistemann
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Martin Exner
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Nico T Mutters
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Steffen Engelhart
- Institute for Hygiene and Public Health, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
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A clinical investigation of dental evacuation systems in reducing aerosols. J Am Dent Assoc 2021; 152:455-462. [PMID: 34044977 PMCID: PMC8142318 DOI: 10.1016/j.adaj.2021.02.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/04/2021] [Accepted: 02/21/2021] [Indexed: 02/08/2023]
Abstract
Background The route of transmission of severe acute respiratory syndrome coronavirus 2 has challenged dentistry to improve the safety for patients and the dental team during various treatment procedures. The purpose of this study was to evaluate and compare the effectiveness of dental evacuation systems in reducing aerosols during oral prophylactic procedures in a large clinical setting. Methods This was a single-center, controlled clinical trial using a split-mouth design. A total of 93 student participants were recruited according to the inclusion and exclusion criteria. Aerosol samples were collected on blood agar plates that were placed around the clinic at 4 treatment periods: baseline, high-volume evacuation (HVE), combination (HVE and intraoral suction device), and posttreatment. Student operators were randomized to perform oral prophylaxis using ultrasonic scalers on 1 side of the mouth, using only HVE suction for the HVE treatment period and then with the addition of an intraoral suction device for the combination treatment period. Agar plates were collected after each period and incubated at 37 °C for 48 hours. Colony-forming unit (CFU) counts were determined using an automatic colony counter. Results The use of a combination of devices resulted in significant reductions in CFUs compared with the use of the intraoral suction device alone (P < .001). The highest amounts of CFUs were found in the operating zone and on patients during both HVE and combination treatment periods. Conclusions Within limitations of this study, the authors found significant reductions in the amount of microbial aerosols when both HVE and an intraoral suction device were used. Practical Implications The combination of HVE and intraoral suction devices significantly decreases microbial aerosols during oral prophylaxis procedures.
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Machado GT, Pinto CRDC, da Fonseca LAV, Ramos TCDS, Paggi TFP, Spira B. Bacteriophages as surrogates for the study of viral dispersion in open air. Arch Microbiol 2021; 203:4041-4049. [PMID: 34046704 PMCID: PMC8158088 DOI: 10.1007/s00203-021-02382-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 05/09/2021] [Accepted: 05/11/2021] [Indexed: 02/07/2023]
Abstract
The SARS-CoV-2 pandemic has revived the debate about the routes of virus transmission and their likelihoods. It is of utmost importance to assess the risks of contamination of susceptible people by infectious individuals and to evaluate the level of SARS-CoV-2 and other respiratory viruses transmission in the community. Most countries have imposed non-pharmaceutical measures to contain SARS-CoV-2 transmission, including physical distancing and mask wearing. Here we evaluated the spreading of viruses in open air using harmless Escherichia coli bacteriophages as a surrogate. Phages were sprayed towards Petri dishes seeded with bacteria at different lengths and angles. Our results showed that the transmission rate decreased exponentially with distance. The highest recorded transmission rate was [Formula: see text] PFU/plate when phages were sprayed from a 1 m distance, suggesting that the probability of transmission of a single virus at a 1 m distance is 1:100,000.
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Affiliation(s)
- Gabriella Trombini Machado
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | | | | | | | - Beny Spira
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil.
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Mourmouris P, Tzelves L, Roidi C, Fotsali A. COVID-19 transmission: a rapid systematic review of current knowledge. Osong Public Health Res Perspect 2021; 12:54-63. [PMID: 33979995 PMCID: PMC8102883 DOI: 10.24171/j.phrp.2021.12.2.02] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/21/2021] [Indexed: 12/12/2022] Open
Abstract
Objective The objective of this study was to identify the potential and definite sources of transmission of coronavirus disease 2019 (COVID-19). Methods Due to time constraints and the acute nature of the pandemic, we searched only PubMed/Medline from inception until January 28, 2021. We analyzed the level of evidence and risk of bias in each category and made suggestions accordingly. Results The virus was traced from its potential origin via possible ways of transmission to the last host. Symptomatic human-to-human transmission remains the driver of the epidemic, but asymptomatic transmission can potentially contribute in a substantial manner. Feces and fomites have both been found to contain viable virus; even though transmission through these routes has not been documented, their contribution cannot be ruled out. Finally, transmission from pregnant women to their children has been found to be low (up to 3%). Conclusion Even though robust outcomes cannot be easily assessed, medical personnel must maintain awareness of the main routes of transmission (via droplets and aerosols from even asymptomatic patients). This is the first attempt to systematically review the existing knowledge to produce a paper with a potentially significant clinical impact.
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Affiliation(s)
- Panagiotis Mourmouris
- Second Department of Urology, Athens Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Lazaros Tzelves
- Second Department of Urology, Athens Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Christiana Roidi
- Second Department of Urology, Athens Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Anastasia Fotsali
- Second Department of Urology, Athens Medical School, National and Kapodistrian University of Athens, Athens, Greece
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