Employment type and non-compliance with SARS-CoV-2 diagnostic testing: insights from a nationwide seroprevalence study in South Korea.

OBJECTIVES

To assess variations in compliance with SARS-CoV-2 diagnostic testing by examining the prevalence of unreported infections according to socioeconomic factors including occupation and employment type. We hypothesised that individuals in more precarious employment conditions would be less likely to undergo COVID-19 testing.

DESIGN

Nationwide follow-up survey linked to a prior seroprevalence study (K-SEROSMART).

SETTING

General population-based study conducted across 258 counties in South Korea.

PARTICIPANTS

The final analysis included 4502 individuals aged 19 years and older who completed both the socioeconomic survey and SARS-CoV-2 antibody testing and were reactive for anti-nucleocapsid (N) antibodies.

PRIMARY OUTCOME MEASURES: The primary outcome was non-compliance with COVID-19 diagnostic testing, defined as the absence of a self-reported confirmed diagnosis among individuals who tested reactive for anti-SARS-CoV-2 nucleocapsid (N) antibodies, indicating a history of natural infection.

RESULTS

Non-compliance with diagnostic testing was significantly associated with socioeconomic characteristics. Self-employed individuals (adjusted OR (aOR) 1.97, 95% CI 1.47 to 2.65) and non-regular workers (aOR 1.45, 95% CI 1.09 to 1.93) had higher odds of unreported infection compared with regular workers. In the analysis by occupational group, certain occupations showed significant associations in the univariate analysis; however, these associations did not retain statistical significance in the multivariable analysis.

CONCLUSIONS

Socioeconomic disparities play an important role in compliance with COVID-19 diagnostic testing. Individuals in precarious employment may face barriers to testing, contributing to undetected infections. Policies that improve access to testing and reduce employment-related constraints, such as paid sick leave, may help mitigate these disparities. Future research should investigate the specific reasons underlying non-compliance with testing and assess its contribution to community transmission.