No, really, get a flu shot: Frequently asked questions about the flu vaccine
November 16, 2021
Fall typically marks the start of cold and flu season in the United States. This year, as SARS-CoV-2 continues to circulate in the community, protecting ourselves and loved ones from flu will be more important than ever. Research shows that getting the flu vaccine can reduce influenza illnesses by 40% to 60%, and if we get the vaccine sooner rather than later, we can avoid a strain on our healthcare system. Here are a few common questions about the flu vaccine to help assuage any doubt that the flu shot is well worth the needle prick.
Why do I need a flu vaccine every year?
We have to get the vaccine every year because the flu virus is constantly changing. So, the flu strains in the vaccine are updated every year by the World Health Organization to ensure it includes inactive strains of the viruses that are predicted to circulate. Unfortunately, we don’t yet have a universal flu vaccine that would protect us from all influenza for all time. Scientists are working on one, but until then, we have to get a vaccine every year.
Does the flu shot wear off?
Yes, the flu shot wears off in about six months. The flu shot does not provide long-lasting protection, which is another reason we need to get one every year.
When should I get a flu shot?
We typically suggest getting the flu shot in the early fall, before the virus starts circulating in the community. It takes about two weeks to be fully protected after vaccination. We don’t know when or if influenza will peak this year, nor do we know what impact COVID-19 and all of our prevention methods like social distancing, vaccination and mask wearing will have on influenza trends. Nevertheless, it’s important to get the vaccine to prevent the flu.
Why is it important to get a flu shot this year?
After almost two years of the COVID-19 pandemic, this year’s flu season is unpredictable. With increasing rates of vaccination against COVID-19, it’s more likely that people will spend time indoors without masks on, increasing their risk of contracting the flu. At the same time, the COVID-19 pandemic is still ongoing, and future waves could put additional strain on the healthcare system. We don’t know what the next few months are going to hold for the pandemic. And if we have a significant COVID-19 resurgence and our healthcare facilities get overwhelmed with COVID-19 patients, then the general public’s access to appointments for the flu and other illnesses may be diminished. So, if there’s a way to get a flu shot now, go ahead and get your flu shot now.
Will the shot inject me with the actual flu virus? Can it give me the flu?
No, the vaccine is made of an inactive version of the flu virus and, therefore, is not infectious. The nasal spray is made of a weakened form of the virus and cannot cause influenza, but may cause a mild runny nose for a day or two. After vaccination, some people may experience other side effects such as a headache, mild fever, or muscle aches for a couple of days; these side effects may contribute to the misconception that the flu shot can give you the flu.
Can I get my flu shot and my COVID-19 vaccine (or booster) at the same time?
Yes, studies have found that it is safe and effective to get both your flu shot and a COVID-19 vaccine at the same time; because the two vaccines are for two different viruses, your body is still able to mount a proper immune response against both of them. If you typically experience side effects after the flu vaccine, or if you had side effects after an earlier dose of the COVID-19 vaccine, you may experience similar side effects after getting both at the same time.
Is it true that the flu shot doesn’t always work?
Yes, it’s true that the flu vaccines won’t always work in everyone who gets it. A person’s immune history has a lot to do with their response to the vaccine. Also, the effectiveness of the vaccine varies each year. However, even when the shot isn’t as effective, it can help minimize how sick people become if they are infected.
Can people with egg allergies still get a flu shot?
Yes, it’s safe for people with egg allergies to get a flu vaccination, including vaccines made in eggs. However, those with a severe egg allergy are encouraged to get the vaccine in a medical setting with supervision by a healthcare provider who can manage an allergic reaction should one occur.
Are non-needle versions of the flu vaccine available?
The nasal flu vaccine was taken off the market for a few years because it was less effective, but it has been reformulated and is now back and available.
Who should not get a flu shot?
Children younger than 6-months-old should not get a flu shot, nor should people with severe, life-threatening allergies to flu vaccines. Those who are immunocompromised should talk with their healthcare provider before getting the vaccine, as should those who are not feeling well. To protect individuals who cannot get the flu shot, it is vitally important that everyone around them get their flu shots.
Allison Bartlett, MD, MS
Allison Bartlett, MD, MS, specializes in the medical management of acute and chronic infectious diseases. She also is working to improve the safety and efficacy of antibiotic use in children.Learn more about Dr. Bartlett.
Protect Yourself and Others from the Flu
UChicago Medicine offers flu shots for adults and children at several downtown, South Side and south suburban locations. Find a flu vaccination clinic near you.Flu Vaccination Clinics