Is it COVID-19 or the flu? New combo tests can find out

In January, a man in his 60s with heart disease and diabetes went to a South Dakota hos- pital with a cough and fever, worried he had COVID. A nurse swabbed the inside of his nose, and the sample went into a small device resembling an inkjet-printer cartridge, which was then placed into a machine about the size of a printer.

This so-called quad test, now available at thousands of U.S. hospitals and clin- ics, could detect not only the coronavirus, but two types of influenza and the respiratory syncytial virus, or RSV. A little more than a half-hour later, Dr. Blake Gustafson had the patient’s result: He had the flu.

“I remember giving myself a fist bump like, ‘Yes! It’s not COVID. It’s the flu,’” said Gustafson, chief of emer- gency medicine of the Sanford USD Medical Center in Sioux Falls, South Dakota. He relayed the news to the patient and his wife, happily adding that there was a treatment he could offer right away, Tamiflu. “The relief in their eyes above their masks was very satisfying,” he said.

The patient’s situation was somewhat unusual this past winter given that the United States, like many other countries, witnessed a shocking absence of a flu season. But as the country begins to reopen, doctors say that flu and other pathogens might make a comeback this autumn. What’s more, even as a growing number of people get vaccinated against COVID, there are still some 40,000 new infections every day in the U.S., and a significant number of people who may be resistant to taking the vaccines.