Flu season is here: Symptoms, shots and side effects

Woman sick on couch

As the change in seasons ushers in cooler weather, it also means the start of flu season. How long flu season lasts can vary but typically begins in November and lasts well into March or early April. 

Here we cover common flu symptoms, possible side effects, vaccine recommendations and answers to common flu-related questions.

Most common flu symptoms

When we talk about the flu (and the vaccine), we refer to the illness caused by the influenza virus. Influenza is a respiratory virus not to be confused with gastrointestinal bugs that are often called the "stomach flu." The most common flu symptoms include:

  • Fever 
  • Body aches 
  • Fatigue 
  • Upper respiratory symptoms that may include a cough, congestion or sore throat 

A person is definitely considered contagious when symptoms are present, but they can potentially spread the flu even before they notice symptoms. 

2022 flu vaccine recommendations

Each year, flu vaccines are created based on predictions of what flu strains may be present in the coming flu season. While these vaccines are very effective, they're not always a 100% match.

"Predicting what the flu season will bring is always a gamble," says Stephen Mohring, MD, Nebraska Medicine primary care physician. "As the COVID-19 pandemic transitions  – especially as wearing masks and practicing social distancing are less utilized – we are concerned that we could see a more significant flu season this year. We recommend vaccination to protect yourself and your loved ones."

Once you are vaccinated, you gain the full amount of protection after two weeks. Receiving the vaccine reduces your chance of getting the flu, the severity of symptoms, and the risk of spreading the virus to others. 

Flu shots are most effective in people under the age of 65. For those over 65, the vaccine significantly reduces the risk of serious illness, helps keep more people out of the hospital and reduces influenza deaths.

What if I'm allergic to eggs?

There is an egg-free vaccine available for those with an egg allergy. If your allergy is mild, you can safely receive the regular vaccine. If you have a severe allergy, talk to your doctor about receiving the egg-free version. 

How does the flu vaccine work?

The vaccine contains elements of the dead influenza virus so the immune system can respond to those specific proteins to make antibodies. When the immune system sees the virus in the future, it ramps up the antibody response to kill it quicker.

When will the flu shot be available?

The flu shot is available now at local pharmacies and Nebraska Medicine clinic locations through early spring. Our recommendation is to get it sooner than later. 

"The best time to get the flu shot is when the flu shot is available," says Dr. Mohring.  There is a two-week time span between vaccination and full protection. Therefore, we recommend getting it in the fall before we start seeing numerous patients getting sick."

Rest assured, it is safe to get the COVID-19 vaccine or booster at the same time as your flu vaccination.

What if I always seem to get sick after getting the flu shot?

You cannot get the flu from the flu shot, but you may experience mild side effects. It's common to feel tenderness at the injection site or mild symptoms for a day or two afterward. 

When you experience mild symptoms, remember that your immune system is doing what it is designed to do: reacting to a foreign antigen and triggering the production of antibodies that will fight the flu in the future. 

Common side effects include:

  • General fatigue
  • Injection site pain 
  • Occasionally, a low-grade fever

Doctor's advice? Think about the timing of your flu shot. Plan it around your life events just in case you feel a few side effects afterward.

Who shouldn't get the flu shot?

Patients with a suppressed immune system should consult their doctor to discuss their best options. Those with a history of Guillain-Barre syndrome, certain autoimmune disorders and those who are sick should avoid getting the flu vaccine.

How do I know if I have influenza or COVID-19?

The symptoms can be challenging to tell apart. If your symptoms last for more than a day or two, perform an at-home COVID-19 test or arrange to get tested. If your symptoms include a fever and body aches, reach out to your doctor.

If you get sick with the flu (even if you've been vaccinated), call your doctor within 24 to 48 hours. Tamiflu is still available as a treatment option and must start within the first few days of symptoms. Wait 24 hours after you are fever free before returning to school or work. Keep yourself and others healthy by practicing healthy habits to prevent flu and colds all season.