Exposure to a SARS-CoV-2 infection at work: development of an international job exposure matrix (COVID-19-JEM)

Objective This study aimed to construct a job exposure matrix (JEM) for risk of becoming infected with the SARS-CoV-2 virus in an occupational setting. Methods Experts in occupational epidemiology from three European countries (Denmark, The Netherlands and the United Kingdom) defined the relevant exposure and workplace characteristics with regard to possible exposure to the SARS-CoV-2 virus. In an iterative process, experts rated the different dimensions of the COVID19-JEM for each job title within the International Standard Classification of Occupations system 2008 (ISCO-08). Agreement scores, weighted kappas, and variances were estimated. Results The COVID-19-JEM contains four determinants of transmission risk [number of people, nature of contacts, contaminated workspaces and location (indoors or outdoors)], two mitigation measures (social distancing and face covering), and two factors for precarious work (income insecurity and proportion of migrants). Agreement scores ranged from 0.27 [95% confidence interval (CI) 0.25–0.29] for ‘migrants’ to 0.76 (95% CI 0.74–0.78) for ‘nature of contacts’. Weighted kappas indicated moderate-to-good agreement for all dimensions [ranging from 0.60 (95% CI 0.60–0.60) for ‘face covering’ to 0.80 (95% CI 0.80–0.80) for ‘contaminated workspaces’], except for ‘migrants’ (0.14 (95% CI-0.07–0.36). As country differences remained after several consensus exercises, the COVID-19-JEM also has a country-axis. Conclusions The COVID-19-JEM assesses the risk at population level using eight dimensions related to SARSCOV-2 infections at work and will improve our ability to investigate work-related risk factors in epidemiological studies. The dimensions of the COVID-19-JEM could also be valuable for other future communicable diseases in the workplace