Publications by authors named "Nadia Wohlwend"

Article Synopsis
  • The study investigates the effects of reducing genomic sequencing on SARS-CoV-2 surveillance outcomes in Switzerland, analyzing over 143,000 sequences.
  • Results show that while some key outcomes like variant detection and cluster analysis could still be achieved with only 35% of the original sequencing effort, this reduction varies significantly by viral lineage.
  • The research highlights the need for genomic surveillance programs to balance cost and public health benefits, emphasizing that reduced sequencing may compromise accuracy in tracking emerging variants of concern.
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Article Synopsis
  • The study examined sex-specific differences in physiological responses to COVID-19 using data from 1,163 participants monitored with a wearable device that measured breathing rate, heart rate, heart rate variability, and skin temperature.
  • Findings revealed that men experienced more significant physiological changes during COVID-19 infection compared to women, including greater increases in skin temperature and breathing rate, as well as greater decreases in heart rate variability.
  • The research highlights the importance of considering sex as a biological variable in health technologies and contributes to the understanding of personalized medicine approaches based on these physiological differences.
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Article Synopsis
  • During the COVID-19 pandemic, the Dr. Risch medical group utilized a specific RT-PCR testing kit for diagnosing infections in Switzerland and Liechtenstein, which targeted three genes essential for identifying the virus.
  • The emergence of the Alpha variant (B.1.1.7) led to a notable diagnostic issue, where the S-gene target was absent due to genetic deletions, marking it as an early indicator of new variants; this phenomenon was also seen in Omicron but not with the Delta variant.
  • Over two years, the group studied the significance of S-gene target failure (SGTF) as a signal for identifying variants, confirming that differences in cycle threshold values could help distinguish true SGTF cases from discrepancies
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Article Synopsis
  • In late 2021, there was a notable increase in N-gene target failures (NGTF) when using the TaqPath COVID-19 test kit, prompting researchers to conduct whole-genome sequencing to investigate the issue.
  • Out of over 168,000 positive samples tested, only 194 (0.12%) failed to amplify the N-gene, predominantly linked to the Delta variant and featuring specific mutations.
  • The study found that specific nucleotide substitutions and deletions were associated with these NGTFs, highlighting the need for combining sequencing with RT-PCR to better tackle diagnostic inaccuracies and monitor emerging variants.
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Objectives: We investigated machinelearningbased identification of presymptomatic COVID-19 and detection of infection-related changes in physiology using a wearable device.

Design: Interim analysis of a prospective cohort study.

Setting, Participants And Interventions: Participants from a national cohort study in Liechtenstein were included.

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Background: In December 2020, the United Kingdom (UK) reported a SARS-CoV-2 Variant of Concern (VoC) which is now named B.1.1.

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Several tests based on chemiluminescence immunoassay techniques have become available to test for SARS-CoV-2 antibodies. There is currently insufficient data on serology assay performance beyond 35 days after symptoms onset. We aimed to evaluate SARS-CoV-2 antibody tests on three widely used platforms.

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Pan-immunoglobulin assays can simultaneously detect IgG, IgM and IgA directed against the receptor binding domain (RBD) of the S1 subunit of the spike protein (S) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 S1-RBD Ig). In this work, we aim to evaluate a quantitative SARS-CoV-2 S1-RBD Ig electrochemiluminescence immunoassay (ECLIA) regarding analytical, diagnostic, operational and clinical characteristics. Our work takes the form of a population-based study in the principality of Liechtenstein, including 125 cases with clinically well-described and laboratory confirmed SARS-CoV-2 infection and 1159 individuals without evidence of coronavirus disease 2019 (COVID-19).

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Knowledge of the sensitivities of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody tests beyond 35 days after the clinical onset of COVID-19 is insufficient. We aimed to describe positivity rate of SARS-CoV-2 assays employing three different measurement principles over a prolonged period. Two hundred sixty-eight samples from 180 symptomatic patients with COVID-19 and a reverse transcription polymerase chain reaction (RT-PCR) test followed by serological investigation of SARS-CoV-2 antibodies were included.

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Background: The principality of Liechtenstein had its first COVID-19 case at the beginning of March 2020. After exponential growth, the pandemic’s first wave was contained, with the last case being diagnosed 52 days after the initial occurrence.

Aim: To characterise the COVID-19 pandemic in Liechtenstein.

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Objectives The sensitivity of molecular and serological methods for COVID-19 testing in an epidemiological setting is not well described. The aim of the study was to determine the frequency of negative RT-PCR results at first clinical presentation as well as negative serological results after a follow-up of at least 3 weeks. Methods Among all patients seen for suspected COVID-19 in Liechtenstein (n=1921), we included initially RT-PCR positive index patients (n=85) as well as initially RT-PCR negative (n=66) for follow-up with SARS-CoV-2 antibody testing.

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Background: The technical, biological, and inter-center reproducibility of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI TOF MS) typing data has not yet been explored. The aim of this study is to compare typing data from multiple centers employing bioinformatics using bacterial strains from two past outbreaks and non-related strains.

Material/methods: Participants received twelve extended spectrum betalactamase-producing E.

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A total of 1,056 native or Cary-Blair-preserved stool specimens were simultaneously tested by conventional stool culturing and by enteric bacterial panel (EBP) multiplex real-time PCR for Campylobacter jejuni, Campylobacter coli, Salmonella spp., and shigellosis disease-causing agents (Shigella spp. and enteroinvasive Escherichia coli [EIEC]).

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Characterization of third-generation-cephalosporin-resistant Klebsiella pneumoniae isolates originating mainly from one human hospital (n = 22) and one companion animal hospital (n = 25) in Bern (Switzerland) revealed the absence of epidemiological links between human and animal isolates. Human infections were not associated with the spread of any specific clone, while the majority of animal infections were due to K. pneumoniae sequence type 11 isolates producing plasmidic DHA AmpC.

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