Long-term care facilities soon may face even longer wait times for COVID-19 PCR test results as diagnostic laboratories warn of a backlog due to surging demand.

“Some [laboratories] could reach or exceed their current testing capacities in the coming days,” cautioned Julie Khani, president of the American Clinical Laboratory Association, on Thursday. “In cases where the number of specimens received exceeds an individual laboratory’s testing capacity, there could be an increase in their average time to deliver results.”

The warning comes as U.S. COVID-19 cases spike upward, including a recent four-fold increase in new weekly nursing home infections. 

Diagnostic laboratories handle molecular (or PCR) tests, one of two options that long-term care operators can use to fulfill mandated COVID-19 testing of residents and staff. While PCR tests offer some advantages over the point-of-care antigen tests that most nursing homes currently have on hand, they also have a longer turnaround time — sometimes requiring days as compared with minutes or hours. Longer delays can limit their usefulness in infection control efforts.

At least a third of facility operators recently have reported test turnaround times that exceed two days, revealing a reluctance to use the antigen tests.

Lab equipment suppliers also have been affected by the increased demand, leading to delays or cancellations on orders for critical supplies such as pipette tips, Khani noted. In addition, the technique of specimen pooling, developed to more efficiently use supplies and increase capacity, only is applicable for populations at low risk or with low prevalence of infection. Pooling is now limited due to increased positivity rates in communities across the country, she said.

“Testing is a vital facet of a public health strategy,” Khani said. “But testing alone is not going to stop the spread of the virus. We must take the actions necessary to contain the virus in all communities.”