What to Expect After You Get a Flu Shot
It’s that time of year again—fall, football season…and flu-shot time. As with most things health-related, you don’t want to put off getting your flu shot too long. Make it a point to roll into your local drugstore to get the jab as soon as you can, with the CDC currently recommending most people get vaccinated by the end of October.
Even if you’re late to the party, the CDC still recommends going in for the shot, as it can still protect you during peak infection season. An added bonus this year is that many pharmacies are letting you get the latest Covid booster at the same time, so you can multitask with this effort.
Of course, as eager as you may be to protect yourself, it’s understandable that you don’t want to be inconvenienced by side effects, which are always a possibility, even if relatively mild. Side effects don’t mean that the shot gave you the flu. Think of them more as a way to know your immune system is working.
Here's the deal: "The flu shot is a killed flu virus that consists of only half of the virus—the part you need to make an immune response to," said Andrew Pekosz, Ph.D., professor of molecular microbiology and immunology at the Johns Hopkins University Bloomberg School of Public Health. "It's then administered into your arm muscle, which is not a place the flu virus normally goes to. So there is no possibility you can get the flu from the flu shot."
But you might have some short-lived symptoms for a few days after the shot, since it has rallied your immune system to attack if a flu virus does actually invade.
Common flu shot side effects include:
Pain, redness or swelling near the shot
Headache
Fever
Nausea
Sore muscles
"Most people have a little redness and soreness at the site of the inoculation. These are normal symptoms and are due in part to your body’s immune system reacting to the vaccine," Pekosz said.
Flu shot side effects you should worry about:
Although extremely rare, it is possible to develop an allergic reaction to the flu shot. Typically, signs appear a few minutes of receiving the vaccine and include:
Trouble breathing
Wheezing
Swelling around eyes or mouth
Hives
Feeling weak
Dizziness
If you are eligible for inoculation via nasal spray (see the CDC's list of people who shouldn't get the nasal spray—including children younger than age 2 and age 50 and older—here), side effects in adults can include a runny nose, headache and cough.
What's new with the 2022-23 flu vaccine?
There are many types of flu viruses–and each consistently changes. This means that the U.S. flu vaccines are reviewed every year to prevent against the currently circulating flu viruses. This year's vaccines are all "quadrivalent," according to the CDC, meaning they're designed to protect against four different viruses that cause the flu.
Additionally, this year, there are three flu vaccines that are preferentially recommended for people age 65 and older (see the CDC's recommendations here).
Can you get the Covid vaccine and a flu shot at the same time?
The CDC says that vaccinations against both diseases can be given at the same time. This year’s latest Covid booster shot came out just in time for flu-shot season, which is extra convenient if you’re aiming to stay up-to-date on both.
Can you still get sick even if you have the shot?
"The flu vaccine protects against influenza virus, but there are a number of other viruses that can cause a flu-like disease,” Pekosz said. "Viruses like human parainfluenza virus, respiratory syncytial virus (RSV) and coronaviruses all circulate in fall and early winter, the time that flu vaccination programs are in full-swing." These viruses and their symptoms usually last two to eight days.
The bottom line on flu shots and side effects
It's normal to feel soreness, redness, tenderness, or even develop a mild fever or body aches during the two days after you get vaccinated—that’s just your immune response, not the flu illness itself.
So there’s no reason to avoid getting the flu shot because you think it’ll make you sick. (Here's how to make the flu shot even more effective.) Unless you have severe or life-threatening allergies to the flu vaccine or any ingredients in it, most people should roll up your sleeves for one each year, the CDC says. (People with severe allergies, those who have had Guillain-Barré syndrome, or who feel ill should talk to their doctor first).
Getting sick with the flu is more dangerous than many people think. While most people will recover, some people can develop complications from the influenza virus, which can include sinus and ear infections, pneumonia, and inflammation of the heart (myocarditis), brain (encephalitis), or muscle (myositis, rhabdomyolysis). It can even be deadly.
You Might Also Like
