Why are you coughing? Multiplex tests can say.
New PCR tests now look simultaneously for multiple viruses—including influenza and the coronavirus.
In January, a man came to Dr. Blake Gustafson’s emergency department in South Dakota with a fever and coughing. He was terrified that he had Covid-19, and wanted to be tested. The patient, who was in his 60s, had multiple preexisting conditions including heart disease and diabetes, which put him at greater risk of severe illness from the new coronavirus. Nurses took a nasal swab from the man, and it was sent for testing.
Except the swab wasn’t just tested for the SARS-CoV-2 virus. It was also tested for influenza A, influenza B and respiratory syncytial virus—all respiratory pathogens that can cause very similar symptoms. Within around half an hour, Dr. Gustafson had an answer. The patient had a virus, but it wasn’t the coronavirus.
My latest article for The New York Times looks at the rise of these ‘multiplex’ tests, which use PCR to test simultaneously for multiple pathogens, and are increasingly common at doctors offices. Those that look concurrently for SARS-CoV-2 and influenza are poised to play an important role if flu returns in the fall. Others, which test for more than 20 different respiratory viruses and bacteria at once, are particularly helpful in hunting down the particular pathogen making an immunocompromised or critically ill individual sick.
Here’s my article about multiplex tests, which could be playing a bigger role in the coming flu season:
Is It Covid or the Flu? New Combo Tests Can Find Out https://www.nytimes.com/2021/05/11/health/covid-tests-flu.html