Global Point of Care

All about the flu

Fever. Chills. A cough and runny nose. They’re classic flu-like symptoms, but they’re also similar to COVID-19 and strep symptoms. A rapid molecular flu test may allow you to get the right treatment sooner and help prevent the spread of the flu to others.3,4

Find a healthcare professional for more information.

Late fall and winter provide an opportunity for the flu to spread5

Although flu viruses spread year-round, infections start to increase in October, leading to peaks between December and February. 

That’s because winter weather and shorter days mean people spend more time crowded together indoors. This gives the virus more opportunity to spread through droplets that are generated when people infected with the virus cough, sneeze or talk.5-7

So as soon as you begin to experience symptoms, make sure you get tested. A rapid molecular flu test may allow you to get the right treatment sooner. Just as important, knowing sooner can help you prevent the spread of the flu to others.3-4

Common symptoms of the flu
  • Fever or chills
  • Sore throat
  • Cough
  • Runny nose
  • Congestion or stuffy nose
  • Headache
  • Muscle or body aches or pains.
  • Feeling tired

Experiencing symptoms?

Learn more about flu symptoms, treatments, and potential complications, as well as how rapid molecular tests can quickly identify the flu virus so you can start the right treatment earlier and get well sooner.


For many people, coming down with the flu means a few days of illness.2,8 Some people may feel tired and weak for several weeks following an infection.9 But the flu can also have severe consequences, especially for people who are younger than 5, older than 65, pregnant or who have certain health conditions like asthma, diabetes and heart disease.2



  • Pneumonia can be caused by the flu virus itself, or by bacteria that takes advantage of your body's weakened state2
  • In general, pneumonia causes over 1 million hospitalizations in the US every year10


  • Inflammation (which can also cause swelling) of the heart, brain or muscle tissues2
  • Multi-organ failure (for example, lung and kidney failure at the same time)2
  • Sepsis, which is the body's response to an infection, happens when an infection (like the flu) you already have triggers a chain reaction througout the body


  • People with asthma may have more asthma attacks when they have the flu, even if their asthma is usually well-controlled2,11
  • People with heart disease are at higher risk of serious flu complications, and flu has been shown to increase the risk of heart attacks and strokes11
  • People with diabetes may find that their blood sugar is harder to control when they are sick with flu11
  • People with chronic kidney disease have a harder time fighting the flu and are at a higher risk of serious illness from the infection11

Targeted treatment begins with a quick diagnosis12

There are medicines available to treat the flu (called antivirals), and they work best when started soon after flu symptoms begin.12

  • Antivirals have been shown to make you feel better, if they are started within two days of flu symptoms.12
  • Since antivirals work best when they are prescribed and used early, rapid molecular tetsing is essential to ensure that your clinician receives quick and accurate results to make a treatment decision.3,12

Because it is both fast and accurate, rapid molecular testing may be the best option to help your clinicians make a treatment decision for you.3,13

sign up

Sign up for Rapid Insights, our email series on rapid molecular testing.

This program will teach you about rapid tests and how they can quickly identify illnesses like the flu, COVID-19, respiratory syncytial virus (RSV), and strep throat. Rapid testing can help you get treated earlier and get well sooner.

Keep reading
  1. “Key Facts About Influenza (Flu).” Centers for Disease Control and Prevention (CDC). Last reviewed August 26, 2021.
  2. “Flu Symptoms & Complications.” Centers for Disease Control and Prevention (CDC). Last reviewed September 21, 2021.
  3. Uyeki, Timothy M., et al. "Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenza." Clinical Infectious Diseases 68, no. 6 (March 15, 2019): e1- e47.
  4. Azar, Marwan., Marie L. Landry. "Detection of Influenza A and B Viruses and Respiratory Syncytial Virus by Use of Clinical Laboratory Improvement Amendments of 1988 (CLIA)-Waived Point-of-Care Assays: A Paradigm Shift to Molecular Tests." Journal of Clinical Microbiology 56, no. 7 (July 2018): e00367-18.
  5. Tamerius, James, et al. "Global Influenza Seasonality: Reconciling Patterns across Temperate and Tropical Regions." Environmental Health Perspectives 119, no. 4 (April 1, 2011): 439-445.
  6. "Flu Season." Centers for Disease Control and Prevention (CDC). Last reviewed September 28, 2021.
  7. "How Flu Spreads." Centers for Disease Control and Prevention (CDC). Last reviewed August 27, 2018.
  8. "Inluenza (flu.)" Mayo Clinic. Accessed December 13, 2021.
  9. Hall, Elisha. "Influenza." Epidemiology and Prevention of Vaccine-Preventable Diseases 14th Edition, edited by Elisha Hall, et al, 179-192. Washington, D.C.: Public Health Foundation, 2021.
  10. "Trends in Pneumonia and Influenza Morbidity and Mortality." American Lung Association. November 2015.
  11. "A Chronic Health Condition Can Increase Your Risk." Centers for Disease Control and Prevention (CDC). Last reviewed November 18, 2021.
  12. "What You Should Know About Flu Antiviral Drugs." Centers for Disease Control and Prevention (CDC). Last reviewed August 31, 2021.
  13. Wabe, Nasir., et al. "The Impact of Rapid Molecular Diagnostic Testing for Respiratory Viruses on Outcomes for Emergency Department Patients." Medical Journal of Australia 210, no. 7 (April 2019): 316-320.