COVID-19 Incidence and Mortality Among Long-Term Care Facility Residents and Staff in South Carolina.

This is observational surveillance data, not a trial, so it cannot prove that any policy, test, mask, quarantine or other measure changed infection or death rates. Resident population counts before 5/17/2020 were assumed constant because mandatory reporting began then, which may distort early incidence and mortality rates. Case reports did not include clinical manifestations of COVID-19 or comprehensive geriatric assessments, so important severity and function details are missing. Staff and resident case trends were parallel, but the study cannot tell whether staff infections caused resident outbreaks or regional spread affected both. The staff comparison uses adults not working in long-term care, and staff had fewer chronic health conditions, so lower death risk may reflect health or healthcare access. Probable cases could be classified using antigen tests, clinical criteria with epidemiologic linkage, or vital records, so case definitions were not all laboratory confirmed by molecular testing.

No funding or conflict-of-interest declaration is reported. The analysis used state public health data under a data use agreement with the South Carolina Department of Health and Environmental Control, and it was approved by the DHEC Institutional Review Board.

Do not conclude that staff testing, masks, quarantine or other policies were proven to reduce spread. The study is observational, many policies came months after the pandemic began, and the authors say the effect of broad policies and the link between staff and resident cases remain unclear.