ABSTRACT
BackgroundPrisons are high-risk environments for Covid-19. Vaccination levels among prison staff remain troublingly low - lower than levels among residents and members of the surrounding community. The situation is troubling because prison staff are a key vector for Covid-19 transmission. ObjectiveTo assess patterns and timing of staff vaccination in California state prisons and identify individual- and community-level factors associated with being unvaccinated. DesignWe calculated fractions of prison staff and incarcerated residents in California state prisons who remained unvaccinated. Adjusted analyses identified demographic, community, and peer factors associated with vaccination uptake among staff. SettingCalifornia Department of Corrections and Rehabilitation prisons. ParticipantsCustody and healthcare staff who worked in direct contact with residents. Main Outcomes and MeasuresRemaining unvaccinated through June 30, 2021. ResultsA total of 26% of custody staff and 52% of healthcare staff took [≥]1 dose in the first two months of vaccine offer; uptake stagnated thereafter. By June 30, 2021, 61% of custody and 37% of healthcare staff remained unvaccinated. Remaining unvaccinated was positively associated with younger age, prior Covid-19, residing in a community with relatively low vaccination rates, and sharing shifts with co-workers who had relatively low vaccination rates. Conclusions and RelevanceVaccine uptake among prison staff in California in regular contact with incarcerated residents has plateaued at levels that pose ongoing risks--both of further outbreaks in the prisons and transmission into surrounding communities. Staff decisions to forego vaccination appear to be complex and multifactorial. Achieving safe levels of vaccine protection among frontline staff may necessitate requiring vaccination as condition of employment.