Identifiability and Estimation Under the Test-negative Design With Population Controls With the Goal of Identifying Risk and Preventive Factors for SARS-CoV-2 Infection

In this study, we consider an alternative design where we recruit among all individuals, symptomatic and asymptomatic, being tested for the virus in addition to population controls. We define a regression parameter related to a prospective risk factor analysis and investigate its identifiability under the two study designs. We review the difference between the prospective risk factor parameter and the parameter targeted in the typical TND where only symptomatic and tested people are recruited. Using missing data directed acyclic graphs, we provide conditions and required data collection under which identifiability of the prospective risk factor parameter is possible and compare the benefits and limitations of the alternative study designs and target parameters. We propose a novel inverse probability weighting estimator and demonstrate the performance of this estimator through simulation study.
Source: Epidemiology - Category: Epidemiology Tags: Infectious Diseases Source Type: research

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Severe acute respiratory syndrome coronavirus 2 (more widely known as COVID-19) appears to have made its global debut in December 2019 in China.1 To date (July 4, 2021), 172,612 publications regarding COVID-19 have been recognized by the United States National Library of Medicine (accessible through PubMed). To put into perspective the massive amount of work that this represents over such a short time, let us turn to the publications regarding the human immunodeficiency virus (HIV), also a pandemic of enormous and continuing global recognition, importance, and cost.
Source: Pediatric Clinics of North America - Category: Pediatrics Authors: Tags: Foreword Source Type: research
Conclusions: Most of the participants had poor knowledge, a positive attitude, and good practices toward COVID-19. Proper counseling of patients and the use of telemedicine could help combat the gap in KAP without compromising the healthcare facilities needed for the management of such patients.
Source: Indian Journal of Dermatology - Category: Dermatology Authors: Source Type: research
This study was conducted to assess family physicians' perception of the US Food and Drug Administration-approved mRNA Coronavirus disease 2019 (COVID-19) vaccines, their plans to be vaccinated with an approved mRNA COVID-19 vaccine, and their support for vaccination of patients and family members. Methods: The authors conducted a cross-sectional survey of 307 practicing family physicians, full-time faculty physicians, and resident physicians in Kansas from December 14, 2020, to December 31, 2020. The study participants completed an anonymous, 20-item survey assessing family physicians' concerns about exposure to COVID-19 ...
Source: Journal of the American Board of Family Medicine - Category: Primary Care Authors: Tags: Original Research Source Type: research
This study analyzes the reasons the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant of concern (VOC) spreads so rapidly. Novel topics such as universal conditions for the rapid spread of respiratory viruses, minimum viral loads for viral aerosol generation, effects of vaccination on viral aerosol generation, and viral aerosol clouds were studied. The analyses were based on experimental results and analytic model studies. Four universal conditions, namely asymptomatic host, high viral load, stability of viruses in air, and binding affinity of viruses to human cells, need to be satisfied for the ra...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Communication Source Type: research
ore Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the novel respiratory disease COVID-19, has reached pandemic status and presents a wide range of manifestations of diverse magnitude, including fever, cough, shortness of breath, and damage to vital organs, such as the heart, lung, kidney, and brain. Normally, older individuals and those with underlying health issues are more at risk. However, about 40% of COVID-19 positive individuals are asymptomatic. This review aims to identify suggested mechanisms of diverse manifestations of COVID-19. Studies suggest that T cell-mediated immunity and s...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Review Source Type: research
The recent release of grant materials from EcoHealth Alliance pertaining to their research with the Wuhan Institute of Virology has been used to demonstrate that gain of function research was funded by the NIH. This conclusion is correct, although not all the experiments done would fall into this category. One of the figures from the […]
Source: virology blog - Category: Virology Authors: Tags: Basic virology Information coronavirus COVID-19 EcoHealth Alliance gain of function pandemic SARS-CoV-2 transgenic mice viral viruses Wuhan Institute of Virology Source Type: blogs
Int Rev Immunol. 2021 Sep 16:1-15. doi: 10.1080/08830185.2021.1967949. Online ahead of print.ABSTRACTSevere Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a recently identified virus responsible for life-threatening coronavirus disease 19 (COVID-19). The SARS-CoV-2 infected subjects can be asymptomatic or symptomatic; the later may present a wide spectrum of clinical manifestations. However, the impact of SARS-CoV-2 on oral diseases remain poorly studied. Detection of SARS-CoV-2 in saliva indicates existence of virus in the oral cavity. Recent studies demonstrating the expression of ACE-2, a SARS-CoV-2 entry rece...
Source: International Reviews of Immunology - Category: Allergy & Immunology Authors: Source Type: research
S Simsek Uzunoglu, H AkcaNigerian Journal of Clinical Practice 2021 24(9):1259-1267 Coronavirus disease 2019 (COVID-19) caused by the new [novel] coronavirus, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a pandemic with exceeding 72 million cases and 1.2 million deaths by the end of November 2020. We aimed to evaluate clinical, laboratory, and radiology findings of COVID-19 in children as reported worldwide and thereby to increase the clinical knowledge about the disease. Bibliographic searches were conducted in December 2020 using PubMed and Google Scholar. The search was limited to children [...
Source: Nigerian Journal of Clinical Practice - Category: Rural Health Authors: Source Type: research
Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a serious infectious disease that has led to a global pandemic with high morbidity and mortality. High-affinity neutralizing antibody is important for controlling infection, which is closely regulated by follicular helper T (Tfh) cells. Tfh cells play a central role in promoting germinal center reactions and driving cognate B cell differentiation for antibody secretion. Available studies indicate a close relationship between virus-specific Tfh cell-mediated immunity and SARS-CoV-2 infection progression....
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
audiu Morgovan Nowadays, humanity is confronted with one of the most difficult challenges. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was identified for the first time in Hubei, China in December 2019 and produced the COVID-19 pandemic, a devastating disease that led to many complications and deaths. The authorities and the global healthcare system have been alerted regarding the prevention and treatment of this pathology. Even though worldwide quarantine was declared, health care professionals, including pharmacists, have been at the frontline in this war. Since the beginning of the pandemic, the aut...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Review Source Type: research
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