It’s that time of year again. And with the beginning of every flu season, questions about the flu vaccine begin to circulate.
An annual flu vaccine is the best way to lower your risk of serious flu illness and hospitalization. It also protects people around you who can’t be vaccinated, especially infants younger than 6 months and people who may be more vulnerable to severe flu illness.
Flu viruses keep changing, so the vaccine is updated every year and your protection needs a yearly refresh to match.
Here’s what you need to know about the flu shot and why it’s so important in protecting yourself (and those around you) from the flu each year.
Who should get a flu shot?
The flu can make anyone sick. Everyone 6 months and older should get a flu vaccine every year, with rare exceptions. This includes healthy kids, teens and adults.
Some people have a higher risk of serious problems if they were to contract the flu. If you live with or care for someone in one of the following groups, getting vaccinated for the flu helps protect them too.
- Children younger than 5
- Adults 65 and older
- People who are pregnant
- People with long-term health conditions or weakened immune systems
- People who live in nursing homes
Flu vaccine and children
The American Academy of Pediatrics recommends annual flu vaccination for children 6 months and older. The vaccines are rigorously tested before they are approved for use, though you should talk with your child's pediatrician about what's right for your family.
Children 8 and younger may need two doses in their first season or if they haven't had two before. Your pediatrician or family healthcare provider may have shots available now, or you can schedule flu shots at an urgent care facility or pharmacy near you.
Pregnancy and the flu shot
Flu can be more serious during pregnancy, and the vaccine protects both you and your baby. The CDC and the American College of Obstetricians and Gynecologists (ACOG) both recommend a flu shot during pregnancy. It can usually be given at the same visit as other inactivated vaccines recommended in pregnancy, such as Tdap.
You can be vaccinated at any point in pregnancy. Early fall is ideal, but later in the season is still worthwhile as long as the flu is circulating.
Vaccination during pregnancy has been linked to a lower risk of flu illness in infants when they're most vulnerable. When a pregnant person gets the flu shot, their body creates antibodies which are passed through the placenta to the developing fetus. This gives newborns protective antibodies during their first few months of life, helping lower their risk of flu illness, before they are old enough to get their own flu vaccine at 6 months.
Talk to your OBGYN at your next prenatal visit about the best timing for your vaccines or if you are due for your flu shot.
The flu shot for adults 65+
Adults 65 and older are at high risk of serious flu problems, as the immune system tends to respond less strongly with age. In the 2024–25 season, this age group made up more than half of flu hospital stays and about 7 in 10 flu deaths, according to CDC estimates.
It is recommended that adults 65 and older get one of three flu vaccines (the Advisory Committee on Immunization Practices, or ACIP, expressed no preference among the three vaccines) that may provide better protection for older adults, if available:
- A high-dose vaccine, which contains four times the amount of antigen, the part of the vaccine that helps your immune system recognize and fight the virus, versus standard-dose flu vaccines
- An adjuvanted vaccine, which has an added ingredient to boost the body's response
- A recombinant vaccine, which is a type of shot created through genetic engineering that does not use chicken eggs or the live flu virus during its manufacturing process
Who should not get the flu shot?
Flu shots are generally safe for most people 6 months and older, but a few groups need to use caution and consult with their doctor before getting vaccinated for the flu.
If you've ever had a severe allergic reaction, such as trouble breathing or swelling of the face or throat, to a previous flu vaccine or something in it, do not get vaccinated until you've talked with your doctor.
If you had Guillain-Barré syndrome, a rare nerve condition, within six weeks of a past flu shot, or you're moderately or severely sick right now, ask your doctor if you should wait.
Previous guidance about not getting a flu shot if you have an egg allergy is no longer a reason to skip the shot. People with an egg allergy can get the flu vaccine that fits their age and health.
When to get a flu shot
The timing of the onset, peak and decline of flu activity can vary from season to season. For most people, the best time to get vaccinated is September or October. That timing helps your protection last through the peak of flu season, which often runs from late fall into winter or early spring.
Getting vaccinated in July or August isn't recommended for most adults, because protection can fade over the season, especially in older adults. You don't need a booster later in the season if you've already been vaccinated this year.
When is it too late to get a flu shot?
If you miss the fall window for a flu shot, don't skip it. The CDC still advises vaccination throughout the season. It takes about two weeks for protection to build, so earlier is better, but later is still worthwhile.
Related: Stages of flu recovery: A day-by-day guide to feeling better fast
Your flu questions, answered
Does the flu shot work? Is it safe? And does it matter if other people get one too? Here are answers to three questions people commonly ask about the flu shot.
1. Does the flu shot work?
Some people question the effectiveness of flu vaccination, and while it doesn't prevent every case, it reduces illness and, most importantly, severe illness.
In 2024–25, the CDC estimated that flu vaccination prevented about 10 million illnesses, 5 million medical visits, 180,000 hospitalizations and 12,000 deaths. That’s a lot of lives saved and illnesses avoided.
How well the flu shot works depends on how closely it matches the flu viruses going around. Researchers work very hard to look at yearly data to try to create a vaccine that best matches the predominant circulating viruses for each season.
Influenza viruses are constantly changing or evolving with new mutations. When a flu virus changes so much that your immune system can no longer recognize it, you can get infected again with a new flu virus.
No vaccine is 100% effective, but the flu shot remains your best defense against the flu.
2. Is the flu shot safe?
Yes, the flu shot is considered safe. Flu vaccines have a long safety record and the vaccine itself does not cause flu illness.
Some people do have reactions that are often mistaken for the flu itself, but they are mild and short-lived. They may include:
- Soreness, redness or swelling where you got the shot
- A low-grade fever
- Muscle aches
- Headache
These reactions are likely due to your body mounting a strong response to the vaccination and a sign that your immune system is working to produce the antibodies it needs to protect itself from the flu.
Whether or not you experience symptoms, your immune system can still develop protection against the flu virus.
3. How does getting vaccinated for the flu help others?
Protecting yourself isn't the only reason to get vaccinated for the flu. Certain groups of people can’t receive the flu vaccine and are at higher risk of serious complications if they were to become ill with the flu.
Community protection through higher vaccination rates is the concept that when most people get the flu vaccine, it helps protect the population by reducing the spread of flu. When too few people are vaccinated, one sick person can spread the flu quickly.
Ready to get your flu shot?
Flu season is here, and the few minutes it takes to get a flu shot can make a big difference for you and the people you care about.
Talk with your doctor if you have questions or concerns about getting a flu shot. Most insurance plans cover flu vaccination, often at no cost, but check with your individual plan.
Schedule your flu shot in MyBSWHealth or find a clinic or pharmacy near you.