[en] 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.
Disciplines :
Immunology & infectious disease
Author, co-author :
El Moussaoui, Majdouline ; Université de Liège - ULiège > Département des sciences cliniques > Immunopathologie - Maladies infectieuses et médecine interne générale
Maes, Nathalie ; Université de Liège - ULiège > Département des sciences de la santé publique
Hong, Samuel L.
Lambert, Nicolas ; Centre Hospitalier Universitaire de Liège - CHU > > Service de neurologie
Bontems, Sébastien ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques > Bactériologie, mycologie, parasitologie, virologie et microbiologie
Defêche, Justine
Godderis, Lode
Molenberghs, Geert
Meuris, Christelle
Artesi, Maria ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques > Génétique humaine
Durkin, Keith ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques > Génétique humaine
Rahmouni, Souad ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques
GREGOIRE, Céline ; Centre Hospitalier Universitaire de Liège - CHU > > Service d'hématologie clinique
BEGUIN, Yves ; Centre Hospitalier Universitaire de Liège - CHU > > Service d'hématologie clinique
MOUTSCHEN, Michel ; Centre Hospitalier Universitaire de Liège - CHU > > Service des maladies infectieuses - médecine interne
Dellicour, Simon
DARCIS, Gilles ; Centre Hospitalier Universitaire de Liège - CHU > > Service des maladies infectieuses - médecine interne
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