Testing Nursing Home Staff Often for COVID Tied to Fewer Resident Deaths

Higher rates of testing for SARS-CoV-2 among staff members at skilled nursing facilities were associated with lower COVID-19 case and deaths rates among residents, according to a retrospective cohort study.

Of the more than 13,000 facilities studied from 2020 to 2022, there were 519.7 cases of COVID per 100 potential outbreaks among residents of high-testing facilities compared with 591.2 cases among residents of low-testing facilities, reported Brian E. McGarry, PT, PhD, of the University of Rochester in New York, and colleagues.

Deaths were also lower in high-testing facilities, with 42.7 deaths per 100 potential outbreaks versus 49.8 deaths in low-testing centers, they noted in the New England Journal of Medicine.

"We found that greater surveillance testing of staff members in skilled nursing facilities was associated with clinically meaningful reductions in COVID-19 cases and deaths among residents," McGarry and team wrote. "Greater surveillance testing was also associated with more COVID-19 cases among staff during potential outbreaks, findings that were consistent with the protection of residents through the increased detection of COVID-19 among staff members."

Although skilled nursing facility staff and residents make up less than 2% of the U.S. population, McGarry and team pointed to a Kaiser Family Foundation report from February 2022 that showed this population accounted for 20% of COVID deaths by the end of 2021.

"Federal authorities have suggested that routine COVID-19 screening of asymptomatic staff be performed up to twice weekly in skilled nursing facilities in areas of high SARS-CoV-2 transmission, although this practice was difficult to achieve at most facilities before 2021 because of testing and staffing shortages, supply-chain issues, and slow turnaround times for test results," they wrote.

When the effects of frequent testing were analyzed over three different time periods -- before vaccine availability, pre-Omicron, and during Omicron -- frequent staff testing was found to be most effective in the period before vaccines were available.

During this period, high- and low-testing facilities had 759.9 cases and 1,060.2 cases, respectively, per 100 potential outbreaks, and 125.2 and 166.8 deaths.

During the pre-Omicron period, case and deaths rates were similar between the high- and low-testing facilities, and during the Omicron wave, cases were lower among high-testing facilities, but death rates were similar.

Of note, larger reductions in COVID cases and deaths were seen when test results were delivered quickly. When average turnaround times were 2 days or less, there were 41.6 resident deaths per 100 potential outbreaks versus 59.1 when results were returned 3 or more days after the test.

"Detection may have occurred earlier in the disease course, thereby disrupting potential viral transmission chains," McGarry and colleagues suggested.

Although there was no significant difference between point-of-care (POC) testing and non-POC testing, the researchers noted that "the use of POC tests avoid delays in laboratory turnaround time."

Moreover, "during the full study period, the use of non-POC tests was associated with only modest reductions in the number of cases and no reduction in deaths," they added. "Because POC tests are less expensive than non-POC tests ($5 vs $100 per test), frequent testing may be more financially feasible with POC testing."

For this study, McGarry and team included 13,424 skilled nursing facilities and assessed staff testing volumes during weeks without COVID cases relative to other skilled nursing facilities in the same county, as well as COVID cases and deaths among residents during potential outbreaks, which were defined as the occurrence of a case after 2 weeks with no cases.

The high-testing facilities fell into the 90th percentile of test volume, and low-testing facilities fell into the 10th percentile.

McGarry and colleagues noted that, due to the observational study design, causality cannot be determined. In addition, unmeasured confounding may have been a driver of differences between high- and low-testing facilities.

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