Occupation and SARS-CoV-2 infection risk among 108 960 workers during the first pandemic wave in Germany

Abstract

Objective: The aim of this study was to identify the occupational risk for a SARS-CoV-2 infection in a nationwide sample of German workers during the first wave of the COVID-19 pandemic (1 February-31 August 2020).

Methods: We used the data of 108 960 workers who participated in a COVID follow-up survey of the German National Cohort (NAKO). Occupational characteristics were derived from the German Classification of Occupations 2010 (Klassifikation der Berufe 2010). PCR-confirmed SARS-CoV-2 infections were assessed from self-reports. Incidence rates (IR) and incidence rate ratios (IRR) were estimated using robust Poisson regression, adjusted for person-time at risk, age, sex, migration background, study center, working hours, and employment relationship.

Results: The IR was 3.7 infections per 1000 workers [95% confidence interval (CI) 3.3-4.1]. IR differed by occupational sector, with the highest rates observed in personal (IR 4.8, 95% CI 4.0-5.6) and business administration (IR 3.4, 95% CI 2.8-3.9) services and the lowest rates in occupations related to the production of goods (IR 2.0, 95% CI 1.5-2.6). Infections were more frequent among essential workers compared with workers in non-essential occupations (IRR 1.95, 95% CI 1.59-2.40) and among highly skilled compared with skilled professions (IRR 1.36, 95% CI 1.07-1.72).

Conclusions: The results emphasize higher infection risks in essential occupations and personal-related services, especially in the healthcare sector. Additionally, we found evidence that infections were more common in higher occupational status positions at the beginning of the pandemic.

Figure 1

SARS-CoV-2 infections by (A) absolute numbers over time and (B) by incidence rates over study centre. Note: the first nationwide lockdown came into force on 22 March and included a ban on gatherings of more than two people not living in the same household. Futher measures included travel restrictions and the closure of schools, daycare centres and non-essential businesses (eg, pubs and cultural institutions). N=108 960 persons.

Figure 2

Risk for SARS-CoV-2 infection (1 February–31 August 2020) among different groups of essential workers in comparison to non-essential workers. Incidence rate ratios obtained from robust Poisson regression analysis (person-time at risk specified as an exposure variable to control for different observation times). Estimations were adjusted for age group (in five-year increments), sex, migration background, study centre, weekly working hours, self-employment, occupational skill level (5^th digit of the KldB-2010), and supervisory/leadership role (4^th digit of the KldB-2010). N=108 960 employed individuals.