5 Things to Know as Flu Season Begins

Seasonal activity of influenza is increasing all across the country, with most patients reporting influenza A.¹ As influenza season ramps up, it is important to know what you can do to both prevent and treat yourself in order to avoid the worst of the influenza symptoms. Here are 5 things you should know about the flu as we move into the beginning of the traditional flu season.

H3N2 Variant Is Most Common Across the Country

A variant of the H3N2 strain is the cause of most cases of the flu so far.² Subclade K emerged too late to be included in the flu vaccine this year, leaving many vulnerable to the spread of this variant. The subclade K H3N2 strain has 7 new mutations, which will likely evade the immunity given to patients by the current vaccine. The emergence of the virus in Japan, the United Kingdom, and Canada has given scientists a heads-up on what form of the flu will be likely to spread in the US, although it is unknown how severe the mutations will end up being.

Symptoms Can Be Similar to COVID-19

Symptoms for the flu and COVID-19 have some overlap, which can make it difficult to identify what is infecting any individual. According to the CDC,³ flu symptoms can include fever, cough, sore throat, runny or stuffy nose, headaches, muscle or body aches, and fatigue. These symptoms are similar to that of COVID-19,⁴ which makes testing for each of influenza and COVID-19 paramount to determining the source of the sickness and the method of addressing the virus. Tests that are capable of testing for all 3 of influenza A, influenza B, and COVID-19 are available to purchase at a local pharmacy.

Making Doctor Appointments Can Reduce Time of Symptoms

Making an appointment with your doctor as symptom onset starts could help in reducing the length of time that symptoms afflict a patient. Antibiotics will not help treat the flu, but doctors may be able to prescribe antivirals, such as oseltamivir phosphate (Tamiflu; Roche), that can help to treat influenza A and B. The medication can help to lessen the time to improvement for patients who are diagnosed with the flu.⁵ If a patient has had symptoms for less than 48 hours, they will be able to use antiviral medications effectively to reduce symptoms of the virus.

Influenza Can Be Treated at Home

Most cases of influenza can be treated at home when the patient is otherwise healthy. Patients can use over-the-counter medications like acetaminophen or nonsteroidal anti-inflammatory drugs to alleviate body aches and lower fever. Those with the flu also should get plenty of rest and drink fluids, like water or broth, to prevent dehydration. Mucus can be cleared out of the lungs by taking expectorants, whereas a nagging cough can be addressed through cough suppressants. Oral decongestants can be used to help a runny or stuffy nose, and heat packs can be used to address aching muscles. A combination of these medications used as needed can help patients get by the worst of their symptoms.

Severe Illness Necessitates Immediate Medical Attention

Despite most healthy individuals being able to address the flu with at-home treatment, between 300,000 and 500,000 individuals need to be hospitalized for the flu each year. Those at highest risk of flu and those who have symptoms that do not improve after 7 to 10 days should immediately see a health care professional. Difficulty breathing, high fever, urinating very little, pain in the chest or stomach, confusion, bluish skin, severe muscle pain, or a fever that goes away but then gets worse are all reasons to immediately seek out the emergency department. Knowing the most severe symptoms of the flu can potentially save the life of someone who is susceptible to the virus.

References

1. Weekly US influenza surveillance report: key updates for week 49, ending December 6, 2025. CDC. December 11, 2025. Accessed December 16, 2025. https://www.cdc.gov/fluview/surveillance/2025-week-49.html
2. Kee C. A new, potentially severe flu variant is spreading in the US. Watch for these symptoms. Today. Updated December 12, 2025. Accessed December 16, 2025. https://www.today.com/health/cold-flu/new-flu-strain-2025-symptoms-rcna243681
3. Signs and symptoms of flu. CDC. August 26, 2024. Accessed December 16, 2025. https://www.cdc.gov/flu/signs-symptoms/index.html
4. Symptoms of COVID-19. CDC. March 10, 2025. Accessed December 16, 2025. https://www.cdc.gov/covid/signs-symptoms/index.html
5. Flu (influenza). Cleveland Clinic. Updated October 11, 2022. Accessed December 16, 2025. https://my.clevelandclinic.org/health/diseases/4335-influenza-flu