Faster COVID-19 test results are critical to saving lives and restarting the economy

Faster results from COVID-19 tests could save hundreds of lives in Illinois and likely thousands of lives nationally, said a Northwestern Medicine disease modeling expert.

Lives would be saved because people who are infected would know sooner and could isolate themselves to protect others from being exposed.

Northwestern experts also said rapid return of test results and increased testing is critical to restart the economy by bringing people back to work and getting children back to school.

Northwestern’s experts comment below on the impact of slow testing results.  They are available for interviews by contacting marla-paul@northwestern.edu.

Jaline Gerardin is an expert in disease modeling and an assistant professor of preventive medicine in epidemiology at Northwestern University Feinberg School of Medicine. She also is on the Illinois COVID-19 Modeling Task Force and a member of Northwestern’s Institute for Global Health.

Gerardin does research in COVID-19 modeling in forecasting and scenario planning, information she provides to the Illinois Department of Public Health and Governor J.B. Pritzker’s office. One critical question the Governor’s office asked was, “How much of a priority is it to decrease test turnaround time?”

“If transmission stays where it was in mid-June, we would save hundreds of lives over the next 9 months by decreasing the time between symptom onset and a positive test result,” Gerardin said. “But if reopening leads to an increase in transmission, the deaths averted would be larger.” 

“In Illinois, at the very least, hundreds of lives would be saved. Nationally, we’d likely save tens of thousands of lives.”  

“Turnaround time for test results in Illinois is highly variable. Hospital settings (about 27% of tests in Illinois as of early July) are very fast, under a day. The slowest are commercial labs (52%) where turnaround can be as long as four to seven days. The Illinois Department of Public Health (21%) can turnaround within a day or two, but if testing sites are sending samples to them via UPS, overall test turnaround time can still be too long. 

“Time between symptom onset and getting a test is also a big issue that needs to be addressed. Every day counts, and we think hundreds of deaths could be averted if day(s) were shaved off the time to diagnosis.

“We need to increase overall testing. In Illinois, we estimate only about 15% of COVID-19 cases are being tested and counted. That still needs to be a lot higher. If we can get testing rates up to 50% or more, improving turnaround time would make an even bigger difference in lives saved.”

Mercedes Carnethon is vice chair and professor of preventive medicine in epidemiology at Northwestern University Feinberg School of Medicine.

“Ensuring rapid return of results is critical as our focus has shifted to restarting our economy by bringing people back to work and getting children back to school,” Carnethon said. “Sensible policies are in place around the timing of return to work that are contingent on getting results back. Some protocols at businesses and in schools are suggesting repeated testing. All of these only work if results are returned quickly.

“The recovery of the economy is also dependent on the return of working parents. In order for daycare facilities and K-12 schools to open, they must have stringent protocols regarding testing and tracing. If results are not returned quickly, children are kept out of schools and daycare facilities longer than necessary. As children are kept out of group care situations, their parents are excluded from the workforce.”

Dr. Sadiya Khan is assistant professor of preventive medicine in epidemiology and a cardiologist at Northwestern University Feinberg School of Medicine.

“Variability in testing time is also an issue of health equity,” Khan said. “Northwestern Medicine is partnering with community clinics to help with access to in-house testing, because many individuals are unable to isolate in low-income homes that may be overcrowded while awaiting testing results. In addition, for those who are essential workers and are left without a rapid result same-day or are living paycheck to paycheck, rapid access to this information is critical not only for public health but also for individual livelihoods and lives.”