Reducing the rates of household transmission: The impact of COVID-19 vaccination in healthcare workers with a known household exposure

Abstract

Objective: To determine the impact of COVID-19 vaccination oninfectionratesin healthcare workers(HCWs) with a householdexposure.

Methods: Retrospectivecohort study8410HCWs(400 fullyvaccinated, 1645partially vaccinated,6365 unvaccinated),employed by a large integrated healthcare system in the southeastern United States,tested for SARS-CoV-2between January 1 and February 26, 2021.

Results: Benefit of vaccination persisted even with household exposure, with unvaccinated HCWs being 3.7 to 7.7 times more likely to be infected than partially or fully vaccinated HCW with positive household contacts respectively (partial OR = 3.73, 95% CI 2.17 - 6.47; full OR = 7.67, CI 2.75 - 21.35). Whereas 89.4% of unvaccinated COVID-positive HCWs with known household exposures were symptomatic, 50% of fully vaccinated HCWs had symptoms, reducing risk of secondary spread from and between HCWs.

Conclusions: COVID-19vaccinationprovided protection against infection evenamongst healthcare workerswithclose household contact,and after adjusting for community prevalence.

Keywords: COVID-19; Healthcare workers; Household transmission; mRNA vaccine.