Scientific article
Open access

Occupational and community risk of SARS-CoV-2 infection among employees of a long-term care facility: an observational study

Published inAntimicrobial resistance and infection control, vol. 11, no. 1, 51
Publication date2022-03-18
First online date2022-03-18

Background: We investigated the contribution of both occupational and community exposure for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among employees of a university-affiliated long-term care facility (LTCF), during the 1stpandemic wave in Switzerland (March-June 2020).

Methods: We performed a nested analysis of a seroprevalence study among all volunteering LTCF staff to determine community and nosocomial risk factors for SARS-CoV-2 seropositivity using modified Poison regression. We also combined epidemiological and genetic sequencing data from a coronavirus disease 2019 (COVID-19) outbreak investigation in a LTCF ward to infer transmission dynamics and acquisition routes of SARS-CoV-2, and evaluated strain relatedness using a maximum likelihood phylogenetic tree.

Results: Among 285 LTCF employees, 176 participated in the seroprevalence study, of whom 30 (17%) were seropositive for SARS-CoV-2. Most (141/176, 80%) were healthcare workers (HCWs). Risk factors for seropositivity included exposure to a COVID-19 inpatient (adjusted prevalence ratio [aPR] 2.6; 95% CI 0.9-8.1) and community contact with a COVID-19 case (aPR 1.7; 95% CI 0.8-3.5). Among 18 employees included in the outbreak investigation, the outbreak reconstruction suggests 4 likely importation events by HCWs with secondary transmissions to other HCWs and patients.

Conclusions: These two complementary epidemiologic and molecular approaches suggest a substantial contribution of both occupational and community exposures to COVID-19 risk among HCWs in LTCFs. These data may help to better assess the importance of occupational health hazards and related legal implications during the COVID-19 pandemic.

  • COVID-19
  • Nosocomial outbreaks
  • Occupational exposure
  • SARS-CoV-2
  • COVID-19 / epidemiology
  • Humans
  • Long-Term Care
  • Nursing Homes
  • Pandemics
  • Phylogeny
  • SARS-CoV-2 / genetics
  • Seroepidemiologic Studies
Citation (ISO format)
LENGGENHAGER, Lauriane et al. Occupational and community risk of SARS-CoV-2 infection among employees of a long-term care facility: an observational study. In: Antimicrobial resistance and infection control, 2022, vol. 11, n° 1, p. 51. doi: 10.1186/s13756-022-01092-0
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Article (Published version)
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ISSN of the journal2047-2994

Technical informations

Creation08/25/2022 7:21:00 AM
First validation08/25/2022 7:21:00 AM
Update time03/16/2023 10:24:04 AM
Status update03/16/2023 10:24:03 AM
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