SARS-CoV-2 antibody prevalence and COVID-19 vaccination among industrial livestock operation workers and nearby community residents, North Carolina, USA

BACKGROUND AND AIM: Industrial livestock operations (ILOs), particularly livestock processing facilities, emerged as centers of COVID-19 outbreaks across the United States early in spring 2020. We aimed to compare SARS-CoV-2-specific IgG positivity and COVID-19 vaccination status among ILO workers and their household members, neighbors of ILOs, and community residents in metropolitan areas of North Carolina, USA. METHODS: This work represents a preliminary analysis within an ongoing study in North Carolina, the 2nd leading hog and turkey and 5th leading broiler chicken producing state. We enrolled 62 of a planned 100 ILO households with at least one adult working at an industrial hog or poultry operation, meatpacking plant, or animal rendering plant, 79 of 100 ILO neighbor (ILON) households, living in close proximity to these facilities but without occupational livestock exposure, and 53 of 100 households in metropolitan areas (Raleigh, Durham, Wilmington) between February 2021 and April 2022 via snowball sampling. Participants responded to a questionnaire and provided a saliva swab sample, which we analyzed for SARS-CoV-2-specific IgG using a multiplex immunoassay. RESULTS: The prevalence of baseline SARS-CoV-2 anti-nucleocapsid IgG, which suggests recent/past SARS-CoV-2 infection, was higher among participants in the ILO compared to participants in the metro (PR=1.7; 95% CI 1.1, 3.0) and ILON (PR=1.6; 95% CI 1.0, 2.4) groups. Similar proportions across groups reached the CDC definition of fully vaccinated (53% of 234 total participants). The ILO group reached full vaccination later (median date: 8/29/21) than the metro (median date: 4/30/21) and ILON (median date: 4/13/21) groups. CONCLUSIONS: Antibody results show high rates of exposure to SARS-CoV-2, especially among ILO workers and their household members. Delays in the timing of receipt of COVID-19 vaccination reinforce the importance of dismantling vaccination barriers for ILO worker populations. KEYWORDS: COVID-19, serology, animal confinement, meatpacking