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Results were promising in a study of a breath test for diagnosing COVID-19 in critically ill patients. The study was published online on Thursday in PLOS ONE.
Lead author Matthew Exline, MD, a pulmonology and critical care expert at the Ohio State University (OSU) Wexner Medical Center, in Columbus, Ohio, and colleagues write, “The ‘breath print’ identified patients with COVID-19 pneumonia with 88% accuracy upon their admission to the ICU [intensive care unit].” Diagnosis took only 15 seconds, the authors say.
The study included 46 ICU patients who were undergoing mechanical ventilation. Of those, 23 had active COVID-19, and 23 did not have COVID. The patients who did not have COVID served as controls for the study. Exhaled breath bags were collected on ICU days 1, 3, 7, and 10 or until the patient was removed from mechanical ventilation.
The breathalyzer detected high concentrations of exhaled nitric oxide in a pattern that was was distinctive for patients with active COVID-19 pneumonia.
Faster, Cheaper Than the Gold Standard
Exline told Medscape Medical News that although the 88% accuracy rate is less than that of the gold-standard molecular tests approved by the US Food and Drug Administration (FDA), the breath test is much faster and cheaper and is less invasive. The FDA-approved molecular tests are reported to have an accuracy of 99%.
Results from reverse transcription polymerase chain reaction (RT-PCR) tests can take many hours, Exline notes. Additionally, with molecular tests, patients have continued to test positive after the infection has resolved.
Exline’s co-author for the study, Perena Gouma, PhD, chair in ceramic engineering at OSU, had been working on the breathalyzer long before the COVID-19 pandemic. She wanted to test it with COVID patients.
It was decided to test the device on patients in the ICU because these patients could be followed over time and it was known that they had severe COVID-19. The researchers were blinded to which patients had COVID-19 and which patients did not.
The researchers are also testing to see whether the breathalyzer can detect COVID-19 in patients who have less severe disease. The patients in that study are outpatients currently at OSU, Exline said.
“We see this as a technology that could in the future be a new, novel way of detecting disease [in addition to] COVID,” he said.
Other Breath Test in the Works
Several centers around the world are working on developing such tests. Exline said, “To our knowledge, no one has a commercially viable breathalyzer.”
He said the advantage of the breathalyzer Gouma designed is that “[w]e would have the ability to change the molecule we’re detecting pretty quickly” if COVID were to eventually change signatures.
The Netherlands rolled out its version of a rapid breath test, called SpiroNose, earlier this year. With that device, people breathe into a machine. The device can indicate a possible SARS-CoV-2 infection within a minute, Reuters reports. Patients who test positive then undergo testing with PCR to confirm that the infection is SARS-CoV-2.
At the Children’s Hospital of Philadelphia, in Pennsylvania, Audrey Odom John, MD, PhD, and colleagues have identified biomarkers in children’s breath that are unique COVID-19.
Their findings were published this year in ACS Infectious Diseases. John is a co-inventor on a preliminary patent for SARS-CoV-2 biomarkers.
Researchers at Rutgers University, in Newark, New Jersey, are working on a breathalyzer that they hope will yield a COVID diagnosis in 10 minutes.
Two startups in Singapore have developed breath tests for COVID-19 that reportedly produce results in less than 2 minutes. According to Nikkei Asia, the tests are designed to be used at large events and for border control.
Marcia Frellick is a freelance journalist based in Chicago. Follow her on Twitter at @mfrellick.