A scratchy, sore throat, a relentless fever, a pounding head and a nasty cough – these symptoms all scream upper respiratory illness. But which one?
Many of the viruses that cause upper respiratory infections such as influenza A or B and the virus that causes COVID-19 all employ similar tactics. They target the same areas in your body – primarily the upper and lower airways – and this shared battleground triggers a similar response from your immune system. Overlapping symptoms – fever, cough, fatigue, aches and pains – make it difficult to determine what may be the underlying cause.
Now, at-home rapid tests can simultaneously determine whether someone has COVID-19 or the flu. Thanks in part to the National Institutes of Health’s Rapid Acceleration of Diagnostics, or RADx, program, the Food and Drug Administration has provided emergency use authorization for seven at-home rapid tests that can distinguish between COVID-19, influenza A and influenza B.
Our team in Atlanta – composed of biomedical engineers, clinicians and researchers at Emory University, Children’s Healthcare of Atlanta and Georgia Institute of Technology – is part of the RADx Test Verification Core. We closely collaborate with other institutions and agencies to determine whether and how well COVID-19 and influenza diagnostics work, effectively testing the tests. Our center has worked with almost every COVID and flu diagnostic on the market, and our data helped inform the instructions you might see in many of the home test kits on the market.
While no test is perfect, to now be able to test for certain viruses at home when symptoms begin can help patients and their doctors come up with appropriate care plans sooner.
A new era of at-home tests
Traditionally, identifying the virus causing upper respiratory illness symptoms required going to a clinic or hospital for a trained medical professional to collect a nasopharyngeal sample. This involves inserting a long, fiber-tipped swab that looks like a skinny Q-tip into one of your nostrils and all the way to the back of your nose and throat to collect virus-containing secretions. The sample is then typically sent to a lab for analysis, which could take hours to days for results.
Thanks to the COVID-19 pandemic, the possibility of using over-the-counter tests to diagnose respiratory illnesses at home became a reality. These tests used a much gentler and less invasive nasal swab and could also be done by anyone, anytime and in their own home. However, these tests were designed to diagnose only COVID-19 and could not distinguish between other types of illnesses.
Since then, researchers have developed over-the-counter multiplex tests that can screen for more than one respiratory infection at once. In 2023, Pfizer’s Lucira test became the first…