Evaluation of Screening Program and Phylogenetic Analysis of SARS-CoV-2 Infections among Hospital Healthcare Workers in Liège, Belgium

Viruses. 2022 Jun 14;14(6):1302. doi: 10.3390/v14061302.

Abstract

Healthcare workers (HCWs) are known to be at higher risk of developing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections although whether these risks are equal across all occupational roles is uncertain. Identifying these risk factors and understand SARS-CoV-2 transmission pathways in healthcare settings are of high importance to achieve optimal protection measures. We aimed to investigate the implementation of a voluntary screening program for SARS-CoV-2 infections among hospital HCWs and to elucidate potential transmission pathways though phylogenetic analysis before the vaccination era. HCWs of the University Hospital of Liège, Belgium, were invited to participate in voluntary reverse transcriptase-polymerase chain reaction (RT-PCR) assays performed every week from April to December 2020. Phylogenetic analysis of SARS-CoV-2 genomes were performed for a subgroup of 45 HCWs. 5095 samples were collected from 703 HCWs. 212 test results were positive, 15 were indeterminate, and 4868 returned negative. 156 HCWs (22.2%) tested positive at least once during the study period. All SARS-CoV-2 test results returned negative for 547 HCWs (77.8%). Nurses (p < 0.05), paramedics (p < 0.05), and laboratory staff handling respiratory samples (p < 0.01) were at higher risk for being infected compared to the control non-patient facing group. Our phylogenetic analysis revealed that most positive samples corresponded to independent introduction events into the hospital. Our findings add to the growing evidence of differential risks of being infected among HCWs and support the need to implement appropriate protection measures based on each individual’s risk profile to guarantee the protection of both HCWs and patients. Furthermore, our phylogenetic investigations highlight that most positive samples correspond to distinct introduction events into the hospital.

Keywords: COVID-19; SARS-CoV-2; healthcare workers; healthcare-associated transmission; infection prevention and control; occupational exposure; phylogenetic analysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Belgium / epidemiology
  • COVID-19* / diagnosis
  • COVID-19* / epidemiology
  • Delivery of Health Care
  • Health Personnel
  • Hospitals, University
  • Humans
  • Personnel, Hospital
  • Phylogeny
  • SARS-CoV-2 / genetics

Grants and funding

The study (2020/155) was supported by the Wallonia Region of Belgium (Convention number 2010075) and Leon Fredericq Foundation (University of Liège). Data from each participant were collected through a questionnaire completed at the time of the first RT-PCR test, except when the subjects also participated in a prospective study on the seroprevalence of anti-SARS-CoV-2 IgG antibodies at our institute (2020/117). S.D. acknowledges support from the Fonds National de la Recherche Scientifique (F.R.S.-FNRS, Belgium; grant n F.4515.22), from the Research Foundation-Flanders (Fonds voor Wetenschappelijk Onderzoek-Vlaanderen, FWO, Belgium; grant n G098321N), and from the European Union Horizon 2020 project MOOD (grant agreement n 874850). Computational resources have been provided by the Consortium des Équipements de Calcul Intensif (CÉCI), funded by the Fonds de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under Grant n 2.5020.11 and by the Walloon Region. G.D. is an F.R.S.-FNRS postdoctoral clinical master’s specialist. S.D. is a F.R.S.-FNRS Research Associate. S.R. is a Senior Research Associate at FNRS. M.E.M. and N.L. are FNRS doctoral clinical specialist candidates.