Differential Risk of SARS-CoV-2 Infection by Occupation: Evidence from the Virus Watch prospective cohort study in England and Wales

A study published in the Journal of Occupational Medicine and Toxicology in 2023 (03/04/2023) examines occupational differences in SARS-CoV-2 infection risk in England and Wales, using data from the Virus Watch cohort study. After adjusting for socio-demographic factors, health-related factors, and non-work public activities, the study found persistent occupational differences in infection risk.

Workers in healthcare, teaching, education and childcare, social care and community protective services, and leisure and personal service occupations showed elevated overall infection risk compared to professional and associate occupations. The study found that belonging to these higher-risk occupations accounted for 13% to 25% of their infection risk.

Most at-risk occupations showed elevated risk in the earlier pandemic phase, which later attenuated for most groups. However, teaching, education, and childcare occupations maintained elevated risk throughout all phases, and healthcare workers also had elevated risk in Wave 4. Among specific frontline occupations, primary school teachers had the highest risk, with their occupation accounting for 40% of their infection risk.

The study suggests that occupation shapes SARS-CoV-2 exposure by influencing factors such as the ability to work from home, practice social distancing, work in well-ventilated environments, and access appropriate personal protective equipment. The changing patterns of risk across pandemic phases are attributed to factors like immunity from prior infection or vaccination, removal of public health restrictions, and the emergence of new variants.

The study’s strengths include a large, diverse cohort, use of multiple data sources, and adjustment for comprehensive confounders. However, limitations include potential residual confounding, challenges in measuring certain factors accurately, and small subsample sizes for some occupations.

The findings highlight the importance of work as a source of infection risk during the COVID-19 pandemic. The study recommends ongoing interventions for persistently high-risk occupations like teaching, and further investigation into the mechanisms underlying differential risk to inform evidence-based public health interventions in the workplace.

The full study can be read here.

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