As flu season begins, you may be worried about getting sick. The number of flu hospitalizations this season have surpassed what has been seen in the last 10 years at this point, and experts have been warning of a tripledemia with the uptick in COVID, RSV and flu cases.
“It’s cause for alarm,” says Dr. Megan Berman, an associate professor of internal medicine at the Sealy Institute for Vaccine Sciences in the University of Texas Health Medical Branch. Fortune.
Experts say a flu shot is your best defense against the virus, but some people choose to skip the shot, lamenting they’ll get infected anyway.
So can you get the flu after getting the vaccine?
You can still get the flu, but it may not be as bad
The flu vaccine typically reduces the risk of getting the flu each year by 40% to 60%, depending on which strain is circulating and how well the vaccine matches that strain.
While the vaccine cannot guarantee that you won’t get sick, it helps protect against serious illnesses that can lead to hospitalization and death, similar to the COVID vaccine. The data found that this year’s flu shot reduces the risk of hospitalization by nearly 50%, according to the US Centers for Disease Control and Prevention (CDC). lung or heart disease, are at higher risk of severe illness from the flu, so the vaccine is crucial to prevent hospitalization in this group.
“When we talk about serious illness, we’re talking about people who are admitted to the hospital, exacerbate underlying chronic conditions, or die from an infection,” says Berman.
In the 2019-2020 flu season, the Centers for Disease Control and Prevention estimates, the vaccine prevented 7.5 million cases of the flu, more than 100,000 hospitalizations, and more than 6,000 deaths.
You can catch the flu before the antibodies kick in
It takes two weeks for the body to mount an immune response after the injection. If you get the flu within that two-week period after getting vaccinated, it’s likely that your body hasn’t yet protected itself against the virus. Also, you may have already had the flu when you received the vaccine.
You may have another virus with similar symptoms
The flu and COVID share a number of symptom, including cough, sore throat, fever, chills and more. If you have flu-like symptoms and have been vaccinated, it may be a different virus. The tests will give a clear answer, says Berman. He typically sees patients who assume they had COVID or the flu based on their symptoms, but rarely have tests. She always tells them that it is better to get tested rather than assume that a particular virus caused the symptoms; it can make many think they are immune to an infection they never had, she says.
“We have the ability to test, and a lot of people just assumed they had something without really knowing it,” she says. “There are a lot of these viruses. They imitate each other.”
There are also different treatments for COVID versus the flu (Paxlovid and Tamiflu respectively).
You may not have as strong an immune response
Those over 65, who make up the majority of flu hospitalizations each year, do not have as strong an immune response to the flu vaccine as younger people. CDC recommends other vaccines for this population, some at higher doses, according to the CDC: Fluzone High-Dose Quadrivalent Vaccine, Flublok Quadrivalent Recombinant Influenza Vaccine, and Fluad Quadrivalent Adjuvanted Influenza Vaccine.
For people receiving immunosuppressive therapy, such as for cancer treatment, or those with an autoimmune disorder, the immune response to the vaccine may also be less effective. If you are over the age of 18, you can get the Flublok vaccine, which may work better for this group.
If the pharmacy doesn’t have the particular flu vaccine you’re looking for, get the general vaccine that’s available.
“Any vaccine is better than no vaccine,” says Berman.
The flu shot can’t give you the flu.
Some worry if the flu shot can actually give you the flu. However, the vaccine is made from an inactivated or killed part of the virus, so it is not possible for the virus to replicate and cause illness.
Your body may have side effects right after the injection, such as fever, headache, nausea, or muscle aches, but this is a sign that the body is mounting an immune response. Side effects go away in a few days.
Since people travel during the holiday season and gather indoors when it’s cold, it’s recommended to do your part and stay protected, even if you’re not at high risk, says Berman. Some people may think they don’t need to get a flu shot, especially since it’s an annual shot. But similar to wearing a seatbelt, getting vaccinated helps protect not only you but those around you from serious outcomes.
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