Rapid flu diagnosis can make the difference in a speedy recovery

Although the mention of the flu evokes memories of bitter syrups, missed work days, and warm chicken soup, it’s a deadly threat for tens of thousands, especially those who are immunocompromised. Between October 1 and March 1, 2025, the United States Center for Disease Control estimates that there have been between 22,000 to 110,000 deaths caused by the flu. Even when it isn’t life threatening, it can still be severe enough to send people to the hospital, decreasing productivity and increasing healthcare burden.

Source: CDC: https://www.cdc.gov/flu-burden/php/data-vis/2024-2025.html

Try as we may, avoiding the flu is nigh impossible. It proliferates in crowds–concerts, parties, workplaces and such. At home, flu can be passed between family members, and in high traffic areas like airports and restaurants, it can reach us on contaminated surfaces. Lifestyle and health factors, such as compromised immune systems or stress, can increase the chances of catching the flu. 

It usually takes around a week for flu symptoms to manifest. Once symptoms begin, so does the game of hope. Uncertainty-induced denial leads us to invent creative excuses: sore throat? Blabbered too much. Running nose? Allergies. Coughing? Too much spicy food. Convincing ourselves that we’re not sick, and ceding rest, can be a funny game to play. But without eliminating the uncertainty, people infected with the flu puts themselves and others at risk.

There were good reasons why people didn’t want to—or flat-out couldn’t—get a diagnosis. Getting a flu test used to require booking a doctor’s appointment and visiting the clinic. The hours of waiting and traveling were not at all appealing. In remote and rural areas, there sometimes aren’t enough resources to accommodate the influx of patient volume during peak flu season, which often coincides with the holidays. However, rapid antigen tests, which were instrumental in identifying COVID, can now be used to diagnose the flu. Affordable, reliable, and accessible, these rapid influenza diagnostic tests provide multiple ways to alleviate fears of not knowing if you have the flu.

Authorized under the U.S. Food and Drug Administration’s Emergency Use Authorization (EUA), a list of such tests can now be purchased over the counter without a prescription. They’re widely available at drug stores and online retailers, such as Amazon. These tests can be performed at home independently.

The WELLlife test kit is an example of the combinational flu and COVID-19 rapid tests authorized under the FDA EUA. Source: WELLlife.

Better yet, many of these tests are also combinational tests that can detect Influenza A, B and COVID-19. Though these illnesses have overlapping symptoms, their treatment requires different processes and medications, so discerning between them at an early stage can ensure the most effective treatment sooner.

To choose a reliable test, Dr. H. James Wedner, an expert in allergy and immunology and a professor at Washington State University, advised paying attention to the Positive Percentage Agreement (the test’s accuracy for positive tests) and the Negative Percent Agreement (the accuracy in detecting negatives). The higher these numbers, the more reliable the test. Users should also consider other factors, such as ease of use, shelf life, and time to produce results.

Although they’re convenient, the FDA noted that as with all tests, there are still chances for false positives and negatives. The Administration recommends those who test positive for flu or COVID-19 to take precautions to prevent spread and consult their healthcare provider for follow-up testing if needed. People experiencing fever, cough, or shortness of breath should seek medical care, even if they test negative.

The FDA has published a list of authorized rapid influenza diagnostic tests.