Nursing homes should consider testing staff members for COVID-19 more frequently after a new study found that the federal government’s coronavirus testing strategy may not be enough to identify asymptotic workers.

A research team, led by experts from Indiana University, suggested that using community spread to dictate staff testing frequency isn’t the best strategy for identifying and stopping potential outbreaks at nursing homes, despite previous findings that there is a correlation between community spread and the case numbers among staff. 

The IU study, which analyzed testing data for nearly 60,000 nursing home workers in Indiana, found that facilities in counties with high positivity rates represented only 17.8% of all facilities statewide, 27.1% of facilities that had a positive staff member and 31.9% of facilities that had three or more staff cases. 

Researchers Kathleen Unroe, MD, and Justin Blackburn, Ph.D., said, based on the findings, providers “should consider whether to test more frequently than these intervals to prevent facility outbreaks, particularly to disrupt staff to resident transmission.” 

“We are still learning how best to utilize antigen and PCR testing. If the goal is identifying any possible asymptomatic positive staff, then we encourage frequent testing across the board. Particularly as capacity for testing picks up as it needs to, the [Centers for Medicare & Medicaid Services] guidance could be considered a floor threshold,” they told McKnight’s Tuesday.  

CMS in September announced that mandatory coronavirus testing of nursing home staff would be based on county-level data. The agency revised the methodology later that same month.

The revised methodology now states that counties with a positivity rate of less than 5% or less than 20 tests in the past 14 days will be classified as green counties. Those with a positivity rate between 5% and 10%, or have less than 500 tests and less than 2,000 tests per 100,000 with a positivity rate of higher than 10%, will be classified as a yellow county. 

Counties that have a 10% positivity rate or higher and don’t meet the criteria for either the green or the yellow standards will be classified as a red county. 

Additionally, it found that facilities in counties with the most cases per 10,000 population represented just 20.6% of all facilities statewide, 30.5% of facilities with one positive case and 36.2% of facilities with three or more cases. 

“In other words, even in areas with low levels of COVID-19 community activity, based on data from Indiana that tested all nursing home staff in the state, facilities in those areas still had infected staff,” Unroe and Blackburn said. 

In an example, researchers said if weekly testing occurred only in facilities within Indiana counties with a positivity rate of 5% or greater, 47.7% of those facilities with a positive case would be identified and 21.2% of facilities without a case would be tested. 

“This strategy may miss over half of the facilities with a SARS-CoV-2 infected staff member, particularly if asymptomatic,” they wrote. 

Full findings were published online Oct. 28 in the Journal of Post-Acute and Long-Term Care Medicine.

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