Publications by authors named "Raymond Tellier"

Article Synopsis
  • Human parechoviruses (HPeVs) are significant causes of central nervous system infections in neonates, with a study conducted in Alberta from 2014 to 2019 focusing on HPeV-3 and the emerging HPeV-5 strains.
  • Among the 18,882 cerebrospinal fluid samples tested, 56 were positive for HPeVs, with a higher prevalence in 2016 and a notable spike in infections during late summer to fall.
  • The study found differences in mean ages of infection (18 days for HPeV-5 vs. 26 days for HPeV-3), and genetic sequencing suggested similarities with a recombinant strain identified in Australia, highlighting the need for ongoing research
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The COVID-19 pandemic has transformed our understanding of aerosol transmissible disease and the measures required to minimise transmission. Anaesthesia providers are often in close proximity to patients and other hospital staff for prolonged periods while working in operating and procedure rooms. Although enhanced ventilation provides some protection from aerosol transmissible disease in these work areas, close proximity and long duration of exposure have the opposite effect.

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Jamestown Canyon virus (JCV) is a mosquitoborne orthobunyavirus in the California serogroup that circulates throughout Canada and the United States. Most JCV exposures result in asymptomatic infection or a mild febrile illness, but JCV can also cause neurologic diseases, such as meningitis and encephalitis. We describe a case series of confirmed JCV-mediated neuroinvasive disease among persons from the provinces of British Columbia, Alberta, Quebec, and Nova Scotia, Canada, during 2011-2016.

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Bronchoalveolar lavage is usually employed for molecular diagnosis of but requires a specialized procedure. By contrast, nasopharyngeal (NP) specimens are easily obtained. In this retrospective study of 35 patients with paired NP and bronchoscopy specimens, NP specimens had a 100% negative percent agreement (95% CI 80.

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Purpose Of Review: The coronavirus disease 2019 pandemic has had a wide-ranging and profound impact on how we think about the transmission of respiratory viruses This review outlines the basis on which we should consider all respiratory viruses as aerosol-transmissible infections, in order to improve our control of these pathogens in both healthcare and community settings.

Recent Findings: We present recent studies to support the aerosol transmission of severe acute respiratory syndrome coronavirus 2, and some older studies to demonstrate the aerosol transmissibility of other, more familiar seasonal respiratory viruses.

Summary: Current knowledge on how these respiratory viruses are transmitted, and the way we control their spread, is changing.

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This is an account that should be heard of an important struggle: the struggle of a large group of experts who came together at the beginning of the COVID-19 pandemic to warn the world about the risk of airborne transmission and the consequences of ignoring it. We alerted the World Health Organization about the potential significance of the airborne transmission of SARS-CoV-2 and the urgent need to control it, but our concerns were dismissed. Here we describe how this happened and the consequences.

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Article Synopsis
  • * Historically, diseases were believed to be transmitted through the air via miasma theory, but this changed with germ theory, which identified various other transmission methods over time.
  • * Recent research, particularly during the COVID-19 pandemic, has reaffirmed the importance of aerosol transmission, indicating that it could be a significant route for many respiratory infections, contrary to previous dominant beliefs.
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The COVID-19 pandemic is the most severe pandemic caused by a respiratory virus since the 1918 influenza pandemic. As is the case with other respiratory viruses, three modes of transmission have been invoked: contact (direct and through fomites), large droplets and aerosols. This narrative review makes the case that aerosol transmission is an important mode for COVID-19, through reviewing studies about bioaerosol physiology, detection of infectious SARS-CoV-2 in exhaled bioaerosols, prolonged SARS-CoV-2 infectivity persistence in aerosols created in the laboratory, detection of SARS-CoV-2 in air samples, investigation of outbreaks with manifest involvement of aerosols, and animal model experiments.

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The potential role of aerosol transmission for seasonal respiratory viruses has been dramatically highlighted during the ongoing COVID-19 pandemic. It is now evident that short-range (conversational) and long-range aerosol transmission plays at least some part in how all these respiratory viruses are transmitted between people. This article highlights and discusses various studies that form the basis for this hypothesis.

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Background: Dengue, chikungunya and zika infections occur in tropical and subtropical regions of the world. We describe the utilization of an in-house nucleic acid test (NAT) targeting all three viruses for febrile returning travelers in Alberta, Canada.

Methods: NAT was performed until 40 days from symptom onset or exposure due to the prolonged duration of zika virus RNA detection.

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Background: Neuromyelitis Optica Spectrum Disorder can be associated with parainfectious and post-infectious triggers. Dengue virus infection is one of the most common arbovirus infections in the world, and may present with neurological manifestations.

Objectives: We present a case of DENV-associated with LETM and positive aquaporin-4 IgG, and a systematic review of published cases.

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Background: As children with isolated vomiting are rarely able to provide a specimen suitable for routine pathogen testing, we have limited knowledge about their infecting pathogens.

Methods: Between December 2014 and August 2018, children <18 years old with presumed acute gastroenteritis who presented to 2 emergency departments (EDs) in Alberta, Canada, were recruited. Eligible participants had ≥3 episodes of vomiting and/or diarrhea in a 24-hour period, <7 days of symptoms, and provided a rectal swab or stool specimen.

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Untreated herpes simplex virus type 1 (HSV-1) encephalitis is associated with high mortality. Missed cases can have devastating consequences. Detection of HSV-1 in cerebrospinal fluid (CSF) with polymerase chain reaction (PCR) is reported to have high sensitivity and specificity and is considered the diagnostic gold standard for HSV-1 encephalitis.

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The objective of this study was to characterize the etiological role of human adenovirus (HAdV) serotypes in pediatric gastroenteritis. Using a case-control design, we compared the frequencies of HAdV serotypes between children with ≥3 episodes of vomiting or diarrhea within 24 h and <7 days of symptoms (i.e.

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Uncertainty about the importance of influenza transmission by airborne droplet nuclei generates controversy for infection control. Human challenge-transmission studies have been supported as the most promising approach to fill this knowledge gap. Healthy, seronegative volunteer 'Donors' (n = 52) were randomly selected for intranasal challenge with influenza A/Wisconsin/67/2005 (H3N2).

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During the rapid rise in COVID-19 illnesses and deaths globally, and notwithstanding recommended precautions, questions are voiced about routes of transmission for this pandemic disease. Inhaling small airborne droplets is probable as a third route of infection, in addition to more widely recognized transmission via larger respiratory droplets and direct contact with infected people or contaminated surfaces. While uncertainties remain regarding the relative contributions of the different transmission pathways, we argue that existing evidence is sufficiently strong to warrant engineering controls targeting airborne transmission as part of an overall strategy to limit infection risk indoors.

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Background: Association between low counts of herpesvirus-specific T cells and subsequent relapse of hematologic malignancy has been shown in two retrospective studies.

Methods: Here we present results of a prospective validation study. Multiple subsets of Epstein-Barr virus (EBV)-specific T cells were measured in 69 patients on day 56 and 84, using intracellular flow cytometry after incubation of blood mononuclear cells (MNCs) with EBV peptides or lysate.

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Measles is one of the most contagious viral respiratory infections and was declared to be eliminated from Canada in 1998; however, measles cases and outbreaks still occur every year through reintroduction from other parts of the world. Laboratory confirmation of measles virus (MV) RNA by real-time PCR provides a definitive diagnosis, and molecular analysis to determine the genotype is the only way to distinguish between wild-type and vaccine strains. This distinction is important since live attenuated vaccine strains are able to replicate in the patient and can be associated with rash and fever but are poorly transmissible, if at all.

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Although short-range large-droplet transmission is possible for most respiratory infectious agents, deciding on whether the same agent is also airborne has a potentially huge impact on the types (and costs) of infection control interventions that are required.The concept and definition of aerosols is also discussed, as is the concept of large droplet transmission, and airborne transmission which is meant by most authors to be synonymous with aerosol transmission, although some use the term to mean either large droplet or aerosol transmission.However, these terms are often used confusingly when discussing specific infection control interventions for individual pathogens that are accepted to be mostly transmitted by the airborne (aerosol) route (e.

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