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1.
Nature ; 520(7547): 307-11, 2015 Apr 16.
Article in English | MEDLINE | ID: mdl-25877200

ABSTRACT

Cell line misidentification, contamination and poor annotation affect scientific reproducibility. Here we outline simple measures to detect or avoid cross-contamination, present a framework for cell line annotation linked to short tandem repeat and single nucleotide polymorphism profiles, and provide a catalogue of synonymous cell lines. This resource will enable our community to eradicate the use of misidentified lines and generate credible cell-based data.


Subject(s)
Cell Line/classification , Cell Line/metabolism , Data Curation , Guidelines as Topic , Cell Separation , Genotype , Microsatellite Repeats/genetics , Polymorphism, Single Nucleotide/genetics , Quality Control , Reproducibility of Results , Species Specificity , Terminology as Topic
2.
Nano Lett ; 20(7): 5544-5552, 2020 07 08.
Article in English | MEDLINE | ID: mdl-32484683

ABSTRACT

The COVID-19 pandemic is currently causing a severe disruption and shortage in the global supply chain of necessary personal protective equipment (e.g., N95 respirators). The U.S. CDC has recommended use of household cloth by the general public to make cloth face coverings as a method of source control. We evaluated the filtration properties of natural and synthetic materials using a modified procedure for N95 respirator approval. Common fabrics of cotton, polyester, nylon, and silk had filtration efficiency of 5-25%, polypropylene spunbond had filtration efficiency 6-10%, and paper-based products had filtration efficiency of 10-20%. An advantage of polypropylene spunbond is that it can be simply triboelectrically charged to enhance the filtration efficiency (from 6 to >10%) without any increase in pressure (stable overnight and in humid environments). Using the filtration quality factor, fabric microstructure, and charging ability, we are able to provide an assessment of suggested fabric materials for homemade facial coverings.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Masks , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Textiles , Aerosols , Air Microbiology , COVID-19 , Coronavirus Infections/transmission , Electricity , Equipment Design , Filtration , Humans , Masks/supply & distribution , Microscopy, Electron, Scanning , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology , Particle Size , Personal Protective Equipment/supply & distribution , Pneumonia, Viral/transmission , SARS-CoV-2
3.
J Infect Dis ; 217(7): 1060-1068, 2018 03 13.
Article in English | MEDLINE | ID: mdl-29294035

ABSTRACT

Epidemics of dengue, Zika, and other arboviral diseases are increasing in frequency and severity. Current efforts to rapidly identify and manage these epidemics are limited by the short diagnostic window in acute infection, the extensive serologic cross-reactivity among flaviviruses, and the lack of point-of-care diagnostic tools to detect these viral species in primary care settings. The Partnership for Dengue Control organized a workshop to review the current landscape of Flavivirus diagnostic tools, identified current gaps, and developed strategies to accelerate the adoption of promising novel technologies into national programs. The rate-limiting step to bringing new diagnostic tools to the market is access to reference materials and well-characterized clinical samples to facilitate performance evaluation. We suggest the creation of an international laboratory-response consortium for flaviviruses with a decentralized biobank of well-characterized samples to facilitate assay validation. Access to proficiency panels are needed to ensure quality control, in additional to in-country capacity building.


Subject(s)
Antibodies, Viral/blood , Dengue/diagnosis , Zika Virus Infection/diagnosis , Antibodies, Viral/immunology , Consumer Product Safety , Dengue/history , Dengue/virology , Dengue Virus/genetics , Dengue Virus/immunology , Dengue Virus/isolation & purification , Enzyme-Linked Immunosorbent Assay/history , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/trends , History, 20th Century , History, 21st Century , Humans , Population Surveillance , Reverse Transcriptase Polymerase Chain Reaction/history , Reverse Transcriptase Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/trends , Sensitivity and Specificity , Zika Virus/genetics , Zika Virus/immunology , Zika Virus/isolation & purification , Zika Virus Infection/history , Zika Virus Infection/virology
4.
MMWR Morb Mortal Wkly Rep ; 63(4): 77-80, 2014 Jan 31.
Article in English | MEDLINE | ID: mdl-24476979

ABSTRACT

Over the past decade, Vietnam has successfully responded to global health security (GHS) challenges, including domestic elimination of severe acute respiratory syndrome (SARS) and rapid public health responses to human infections with influenza A(H5N1) virus. However, new threats such as Middle East respiratory syndrome coronavirus (MERS-CoV) and influenza A(H7N9) present continued challenges, reinforcing the need to improve the global capacity to prevent, detect, and respond to public health threats. In June 2012, Vietnam, along with many other nations, obtained a 2-year extension for meeting core surveillance and response requirements of the 2005 International Health Regulations (IHR). During March-September 2013, CDC and the Vietnamese Ministry of Health (MoH) collaborated on a GHS demonstration project to improve public health emergency detection and response capacity. The project aimed to demonstrate, in a short period, that enhancements to Vietnam's health system in surveillance and early detection of and response to diseases and outbreaks could contribute to meeting the IHR core capacities, consistent with the Asia Pacific Strategy for Emerging Diseases. Work focused on enhancements to three interrelated priority areas and included achievements in 1) establishing an emergency operations center (EOC) at the General Department of Preventive Medicine with training of personnel for public health emergency management; 2) improving the nationwide laboratory system, including enhanced testing capability for several priority pathogens (i.e., those in Vietnam most likely to contribute to public health emergencies of international concern); and 3) creating an emergency response information systems platform, including a demonstration of real-time reporting capability. Lessons learned included awareness that integrated functions within the health system for GHS require careful planning, stakeholder buy-in, and intradepartmental and interdepartmental coordination and communication.


Subject(s)
Capacity Building/organization & administration , Disease Outbreaks/prevention & control , Global Health , International Cooperation , Population Surveillance , Centers for Disease Control and Prevention, U.S. , Humans , United States , Vietnam , World Health Organization
5.
Nat Genet ; 37(2): 153-9, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15640799

ABSTRACT

Francisella tularensis is one of the most infectious human pathogens known. In the past, both the former Soviet Union and the US had programs to develop weapons containing the bacterium. We report the complete genome sequence of a highly virulent isolate of F. tularensis (1,892,819 bp). The sequence uncovers previously uncharacterized genes encoding type IV pili, a surface polysaccharide and iron-acquisition systems. Several virulence-associated genes were located in a putative pathogenicity island, which was duplicated in the genome. More than 10% of the putative coding sequences contained insertion-deletion or substitution mutations and seemed to be deteriorating. The genome is rich in IS elements, including IS630 Tc-1 mariner family transposons, which are not expected in a prokaryote. We used a computational method for predicting metabolic pathways and found an unexpectedly high proportion of disrupted pathways, explaining the fastidious nutritional requirements of the bacterium. The loss of biosynthetic pathways indicates that F. tularensis is an obligate host-dependent bacterium in its natural life cycle. Our results have implications for our understanding of how highly virulent human pathogens evolve and will expedite strategies to combat them.


Subject(s)
Francisella tularensis/genetics , Genome, Bacterial , Base Sequence , DNA Transposable Elements , Francisella tularensis/growth & development , Genomic Islands , Iron/metabolism , Molecular Sequence Data , Mutation , Sequence Analysis, DNA , Virulence/genetics
6.
Heliyon ; 10(12): e32780, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39022029

ABSTRACT

This study investigated the effects of incorporating carbon nanotubes (CNTs) into rice husk ash (RHA) sustainable concrete on its mechanical properties, permeability and microstructure characterisation. Mechanical test results suggested that the addition of 0.10 % multiwalled CNTs (MWCNTs) yielded optimal results, with increases in the compressive strength, splitting tensile strength, flexural strength, and elastic modulus of the RHA concrete at 28 days of 7 %, 23.81 %, 17.5 %, and 1.0 %, respectively. However, with further addition of MWCNTs, the mechanical properties ultimately deteriorated. Further, the incorporation of CNTs enhanced the long-term performance of RHA sustainable concrete. The addition of 0.1 % MWCNTs and 15 % RHA yielded a 20 %, 14 %, and 66 % decrease in water absorption, porosity, and chloride diffusion coefficient compared to the mixture solely containing 15 % RHA. Scanning electron microscopy of this mixture revealed the filling and bridging effects of MWCNTs between the hydration products have enhanced the performance of RHA sustainable concrete.

7.
Int J Epidemiol ; 52(1): 32-43, 2023 02 08.
Article in English | MEDLINE | ID: mdl-36164817

ABSTRACT

BACKGROUND: There has been a large influx of COVID-19 seroprevalence studies, but comparability between the seroprevalence estimates has been an issue because of heterogeneities in testing platforms and study methodology. One potential source of heterogeneity is the response or participation rate. METHODS: We conducted a review of participation rates (PR) in SARS-CoV-2 seroprevalence studies collected by SeroTracker and examined their effect on the validity of study conclusions. PR was calculated as the count of participants for whom the investigators had collected a valid sample, divided by the number of people invited to participate in the study. A multivariable beta generalized linear model with logit link was fitted to determine if the PR of international household and community-based seroprevalence studies was associated with the factors of interest, from 1 December 2019 to 10 March 2021. RESULTS: We identified 90 papers based on screening and were able to calculate the PR for 35 out of 90 papers (39%), with a median PR of 70% and an interquartile range of 40.92; 61% of the studies did not report PR. CONCLUSIONS: Many SARS-CoV-2 seroprevalence studies do not report PR. It is unclear what the median PR rate would be had a larger portion not had limitations in reporting. Low participation rates indicate limited representativeness of results. Non-probabilistic sampling frames were associated with higher participation rates but may be less representative. Standardized definitions of participation rate and data reporting necessary for the PR calculations are essential for understanding the representativeness of seroprevalence estimates in the population of interest.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/epidemiology , Seroepidemiologic Studies , Linear Models , Research Design , Antibodies, Viral
8.
PLOS Glob Public Health ; 3(10): e0001568, 2023.
Article in English | MEDLINE | ID: mdl-37819913

ABSTRACT

We present a framework for a federated, virtual biorepository system (VBS) with locally collected and managed specimens, as a 'global public good' model based on principles of equitable access and benefit sharing. The VBS is intended to facilitate timely access to biological specimens and associated data for outbreak-prone infectious diseases to accelerate the development and evaluation of diagnostics, assess vaccine efficacy, and to support surveillance and research needs. The VBS is aimed to be aligned with the WHO BioHub and other specimen sharing efforts as a force multiplier to meet the needs of strengthening global tools for countering epidemics. The purpose of our initial research is to lay the basis of the collaboration, management and principles of equitable sharing focused on low- and middle-income country partners. Here we report on surveys and interviews undertaken with biorepository-interested parties to better understand needs and barriers for specimen access and share examples from the ZIKAlliance partnership on the governance and operations of locally organized biorepositories.

9.
Vaccines (Basel) ; 10(12)2022 Nov 24.
Article in English | MEDLINE | ID: mdl-36560415

ABSTRACT

Background: Many serological assays to detect SARS-CoV-2 antibodies were developed during the COVID-19 pandemic. Differences in the detection mechanism of SARS-CoV-2 serological assays limited the comparability of seroprevalence estimates for populations being tested. Methods: We conducted a systematic review and meta-analysis of serological assays used in SARS-CoV-2 population seroprevalence surveys, searching for published articles, preprints, institutional sources, and grey literature between 1 January 2020, and 19 November 2021. We described features of all identified assays and mapped performance metrics by the manufacturers, third-party head-to-head, and independent group evaluations. We compared the reported assay performance by evaluation source with a mixed-effect beta regression model. A simulation was run to quantify how biased assay performance affects population seroprevalence estimates with test adjustment. Results: Among 1807 included serosurveys, 192 distinctive commercial assays and 380 self-developed assays were identified. According to manufacturers, 28.6% of all commercial assays met WHO criteria for emergency use (sensitivity [Sn.] >= 90.0%, specificity [Sp.] >= 97.0%). However, manufacturers overstated the absolute values of Sn. of commercial assays by 1.0% [0.1, 1.4%] and 3.3% [2.7, 3.4%], and Sp. by 0.9% [0.9, 0.9%] and 0.2% [−0.1, 0.4%] compared to third-party and independent evaluations, respectively. Reported performance data was not sufficient to support a similar analysis for self-developed assays. Simulations indicate that inaccurate Sn. and Sp. can bias seroprevalence estimates adjusted for assay performance; the error level changes with the background seroprevalence. Conclusions: The Sn. and Sp. of the serological assay are not fixed properties, but varying features depending on the testing population. To achieve precise population estimates and to ensure the comparability of seroprevalence, serosurveys should select assays with high performance validated not only by their manufacturers and adjust seroprevalence estimates based on assured performance data. More investigation should be directed to consolidating the performance of self-developed assays.

10.
Am J Infect Control ; 50(8): 890-897, 2022 08.
Article in English | MEDLINE | ID: mdl-35908828

ABSTRACT

BACKGROUND: SARS-CoV-2 emerged in 2019 and resulted in a pandemic causing millions of infections worldwide. Gold-standard for SARS-CoV-2 detection uses quantitative RT-qPCR on respiratory secretions to detect viral RNA (vRNA). Acquiring these samples is invasive, can be painful for those with xerostomia and other health conditions, and sample quality can vary greatly. Frequently only symptomatic individuals are tested even though asymptomatic individuals can have comparable viral loads and efficiently transmit virus. METHODS: We utilized a non-invasive approach to detect SARS-CoV-2 in individuals, using polyvinyl alcohol (PVA) strips embedded in KN95 masks. PVA strips were tested for SARS-CoV-2 vRNA via qRT-PCR and infectious virus. RESULTS: We show efficient recovery of vRNA and infectious virus from virus-spiked PVA with detection limits comparable to nasal swab samples. In infected individuals, we detect both human and SARS-CoV-2 RNA on PVA strips, however, these levels are not correlated with length of time mask was worn, number of times coughed or sneezed, or level of virus in nasal swab samples. We successfully cultured and deep-sequenced PVA-associated virus. CONCLUSIONS: These results demonstrate the feasibility of using PVA-embedded masks as a non-invasive platform for detecting SARS-CoV-2 in exhaled air in COVID-positive individuals regardless of symptom status.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , COVID-19 Testing , Humans , Pandemics , RNA, Viral/analysis , RNA, Viral/genetics
11.
Am J Trop Med Hyg ; 106(2): 562-565, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34996045

ABSTRACT

The dried-tube specimen (DTS) procedure was used to develop the COVID-19 serology control panel (CSCP). The DTS offers the benefit of shipping materials without a cold chain, allowing for greater access without deterioration of material integrity. Samples in the panel were sourced from COVID-19 convalescent persons from March to May 2020. The immunoglobulin subtypes (total Ig, IgM, and IgG) and their respective reactivity to severe acute respiratory syndrome coronavirus 2 nucleocapsid, spike, and receptor-binding domain antigens of the samples were delineated and compared with the WHO International Standard to elucidate the exact binding antibody units of each CSCP sample and ensure the CSCP provides adequate reactivity for different types of serological test platforms. We distribute the CSCP as a kit with five coded tubes to laboratories around the world to be used to compare test kits for external quality assurance, for harmonizing laboratory testing, and for use as training materials for laboratory workers.


Subject(s)
COVID-19 Serological Testing/methods , COVID-19/diagnosis , SARS-CoV-2/immunology , Specimen Handling/methods , Antibodies, Viral/blood , COVID-19 Serological Testing/standards , Coronavirus Nucleocapsid Proteins/immunology , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Specimen Handling/standards , Spike Glycoprotein, Coronavirus/immunology , World Health Organization
12.
JMIR Res Protoc ; 11(12): e36549, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36454625

ABSTRACT

BACKGROUND: The design of personal protective equipment (PPE) may affect well-being and clinical work. PPE as an integrated item may improve usability and increase adherence by healthcare professionals. Human factors design and safety may reduce occupational-acquired diseases. As an integrated PPE, a lightweight protective air-purifying respirator (L-PAPR) could be used during health procedures where healthcare professionals are exposed to airborne pathogens. The human factors affecting the implementation of alternative PPE such as L-PAPR have not been thoroughly studied. The population of interest is health care professionals, the intervention is the performance by PPE during tasks across the three PPE types 1.) N95 respirators and face shields, 2.)traditional powered air-purifying respirator(PAPR), and 3.) L-PAPR. The outcomes are user error, communications, safety, and end-user preferences. OBJECTIVE: This study will assess whether the L-PAPR improves health care professionals' comfort in terms of perceived workload and physical and psychological burden during direct patient care when compared with the traditional PAPR or N95 and face shield. This study also aims to evaluate human factors during the comparison of the use of L-PAPR with a combination of N95 respirators plus face shields or the traditional PAPRs. METHODS: This is an interventional randomized crossover quality improvement feasibility study consisting of a 3-site simulation phase with 10 participants per site and subsequent field testing in 2 sites with 30 participants at each site. The 3 types of respiratory PPE will be compared across medical tasks and while donning and doffing. We will evaluate the user's perceived workload, usability, usage errors, and heart rate. We will conduct semistructured interviews to identify barriers and enablers to implementation across each PPE type over a single continuous wear episode and observe interpersonal communications across conditions and PPE types. RESULTS: We expect the research may highlight communication challenges and differences in usability and convenience across PPE types along with error frequency during PPE use across PPE types, tasks, and time. CONCLUSIONS: The design of PPE may affect overall well-being and hinder or facilitate clinical work. Combining 2 pieces of PPE into a single integrated item may improve usability and reduce occupational-acquired diseases. The human factors affecting the implementation of an alternative PPE such as L-PAPR or PAPR have not been thoroughly studied. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/36549.

13.
Front Microbiol ; 13: 893801, 2022.
Article in English | MEDLINE | ID: mdl-35707164

ABSTRACT

Background: There is an urgent need for harmonization between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serology platforms and assays prior to defining appropriate correlates of protection and as well inform the development of new rapid diagnostic tests that can be used for serosurveillance as new variants of concern (VOC) emerge. We compared multiple SARS-CoV-2 serology reference materials to the WHO International Standard (WHO IS) to determine their utility as secondary standards, using an international network of laboratories with high-throughput quantitative serology assays. This enabled the comparison of quantitative results between multiple serology platforms. Methods: Between April and December 2020, 13 well-characterized and validated SARS-CoV-2 serology reference materials were recruited from six different providers to qualify as secondary standards to the WHO IS. All the samples were tested in parallel with the National Institute for Biological Standards and Control (NIBSC) 20/136 and parallel-line assays were used to calculate the relevant potency and binding antibody units. Results: All the samples saw varying levels of concordance between diagnostic methods at specific antigen-antibody combinations. Seven of the 12 candidate materials had high concordance for the spike-immunoglobulin G (IgG) analyte [percent coefficient of variation (%CV) between 5 and 44%]. Conclusion: Despite some concordance between laboratories, qualification of secondary materials to the WHO IS using arbitrary international units or binding antibody units per milliliter (BAU/ml) does not provide any benefit to the reference materials overall, due to the lack of consistent agreeable international unit (IU) or BAU/ml conversions between laboratories. Secondary standards should be qualified to well-characterized reference materials, such as the WHO IS, using serology assays that are similar to the ones used for the original characterization of the WHO IS.

14.
BMJ Open ; 12(11): e061029, 2022 11 23.
Article in English | MEDLINE | ID: mdl-36418127

ABSTRACT

INTRODUCTION: This study aims to measure how transmission of SARS-CoV-2 occurs in communities and to identify conditions that lend to increased transmission focusing on congregate situations. We will measure SARS-CoV-2 in exhaled breath of asymptomatic and symptomatic persons using face mask sampling-a non-invasive method for SARS-CoV-2 detection in exhaled air. We aim to detect transmission clusters and identify risk factors for SARS-CoV-2 transmission in presymptomatic, asymptomatic and symptomatic individuals. METHODS AND ANALYSIS: In this observational prospective study with daily follow-up, index cases and their respective contacts are identified at each participating institution. Contact definitions are based on Centers for Disease Control and Prevention and local health department guidelines. Participants will wear masks with polyvinyl alcohol test strips adhered to the inside for 2 hours daily. The strips are applied to all masks used over at least 7 days. In addition, self-administered nasal swabs and (optional) finger prick blood samples are performed by participants. Samples are tested by standard PCR protocols and by novel antigen tests. ETHICS AND DISSEMINATION: This study was approved by the Colorado Multiple Institutional Review Board and the WHO Ethics Review Committee. From the data generated, we will analyse transmission clusters and risk factors for transmission of SARS-CoV-2 in congregate settings. The kinetics of asymptomatic transmission and the evaluation of non-invasive tools for detection of transmissibility are of crucial importance for the development of more targeted control interventions-and ultimately to assist with keeping congregate settings open that are essential for our social fabric. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (#NCT05145803).


Subject(s)
COVID-19 , Masks , Humans , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , Observational Studies as Topic , Personal Protective Equipment , Prospective Studies , SARS-CoV-2
15.
Ann N Y Acad Sci ; 1518(1): 209-225, 2022 12.
Article in English | MEDLINE | ID: mdl-36183296

ABSTRACT

The COVID-19 pandemic caught the world largely unprepared, including scientific and policy communities. On April 10-13, 2022, researchers across academia, industry, government, and nonprofit organizations met at the Keystone symposium "Lessons from the Pandemic: Responding to Emerging Zoonotic Viral Diseases" to discuss the successes and challenges of the COVID-19 pandemic and what lessons can be applied moving forward. Speakers focused on experiences not only from the COVID-19 pandemic but also from outbreaks of other pathogens, including the Ebola virus, Lassa virus, and Nipah virus. A general consensus was that investments made during the COVID-19 pandemic in infrastructure, collaborations, laboratory and manufacturing capacity, diagnostics, clinical trial networks, and regulatory enhancements-notably, in low-to-middle income countries-must be maintained and strengthened to enable quick, concerted responses to future threats, especially to zoonotic pathogens.


Subject(s)
COVID-19 , Ebolavirus , Humans , Pandemics , COVID-19/epidemiology , Disease Outbreaks
16.
Article in English | MEDLINE | ID: mdl-34360373

ABSTRACT

There are many hidden safety hazards in homemade food due to an absence of food preparation and storage knowledge, and this has led to many food safety incidents. The purpose of this study was to explore the influencing factors of consumers' food risk communication behavior on social media in northeast China, using the protection motivation theory. We integrate the Suan Tang Zi food poisoning accident and the protection motivation theory to develop a conceptual model to predict food safety risk communication on social media. We conducted a questionnaire which adapted measures from the existing Likert scales. A total of 789 respondents from northeast China participated in this study. We tested our hypotheses using a structural equation model. Results show that perceived severity, perceived vulnerability and self-efficacy have a significant influence on consumer protection motivation. Response efficacies have a positive impact on consumer protection motivation, but response barriers have a negative impact on consumer protection motivation. Additionally, information need and protection motivation of consumers have a significant impact on food safety risk communication on social media. Overall, the protection motivation theory accounted for 71% of the variance in food safety risk communication on social media. Practical implications and suggestions are proposed for the related stakeholders, as well as consumers, to encourage the public to participate in the food risk communication in this study. The research findings presented the social media as a kind of food risk communication channel contributes to consumers acquire accurate information on food quickly, in turn, reduce the probability of food poisoning in daily life. Protection motivation theory may provide some insights into how we can increase the rate of food safety risk communication on social media.


Subject(s)
Motivation , Social Media , Accidents , Communication , Consumer Behavior , Food Safety , Humans
18.
Antimicrob Resist Infect Control ; 9(1): 126, 2020 08 06.
Article in English | MEDLINE | ID: mdl-32762735

ABSTRACT

Currently available evidence supports that the predominant route of human-to-human transmission of the SARS-CoV-2 is through respiratory droplets and/or contact routes. The report by the World Health Organization (WHO) Joint Mission on Coronavirus Disease 2019 (COVID-19) in China supports person-to-person droplet and fomite transmission during close unprotected contact with the vast majority of the investigated infection clusters occurring within families, with a household secondary attack rate varying between 3 and 10%, a finding that is not consistent with airborne transmission. The reproduction number (R0) for the SARS-CoV-2 is estimated to be between 2.2-2.7, compatible with other respiratory viruses associated with a droplet/contact mode of transmission and very different than an airborne virus like measles with a R0 widely cited to be between 12 and 18. Based on the scientific evidence accumulated to date, our view is that SARS-CoV-2 is not spread by the airborne route  to  any significant extent and the use of particulate respirators offers no advantage over medical masks as a component of personal protective equipment for the routine care of patients with COVID-19 in the health care setting. Moreover, prolonged use of particulate respirators may result in unintended harms. In conjunction with appropriate hand hygiene, personal protective equipment (PPE) used by health care workers caring for patients with COVID-19 must be used with attention to detail and precision of execution to prevent lapses in adherence and active failures in the donning and doffing of the PPE.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/prevention & control , Health Personnel/statistics & numerical data , Infection Control/instrumentation , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , COVID-19 , China/epidemiology , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Coronavirus Infections/virology , Humans , Infection Control/methods , Masks , Personal Protective Equipment , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , SARS-CoV-2 , Ventilators, Mechanical
19.
Radiat Res ; 171(1): 127-39, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19138057

ABSTRACT

The World Health Organization (WHO) held a consultation meeting at WHO Headquarters, Geneva, Switzerland, December 17-18, 2007, to develop the framework for a global biodosimetry network. The WHO network is envisioned to enable dose assessment using multiple methods [cytogenetics, electron paramagnetic resonance (EPR), radionuclide bioassays, etc.]; however, the initial discussion focused on the cytogenetic bioassay (i.e., metaphase-spread dicentric assay). Few regional cytogenetic biodosimetry networks have been established so far. The roles and resources available from United Nations (UN) agencies that provide international cooperation in biological dosimetry after radiological emergencies were reviewed. In addition, extensive reliance on the use of the relevant International Standards Organization (ISO) standards was emphasized. The results of a WHO survey of global cytogenetic biological dosimetry capability were reported, and while the survey indicates robust global capability, there was also a clear lack of global leadership and coordination. The expert group, which had a concentrated focus on cytogenetic biodosimetry, formulated the general scope and concept of operations for the development of a WHO global biodosimetry laboratory network for radiation emergencies (BioDoseNet). Follow-on meetings are planned to further develop technical details for this network.


Subject(s)
Internationality , Laboratories/organization & administration , Radioactive Hazard Release , Radiometry/methods , World Health Organization , Data Collection , Humans , Laboratories/standards , Patient Selection , Physicians , Radiometry/standards , Reference Values , Specimen Handling
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