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You Can’t Get the Flu from the Flu Shot – But Here Are Some Reasons People Think You Can

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You Can’t Get the Flu from the Flu Shot – But Here Are Some Reasons People Think You Can

Dec 22, 2014

It’s true that the flu shot contains the flu itself, but it won’t make you ill. Dr. Suzan Terry lists reasons why people think they may have gotten the flu from the flu shot and describes what’s actually happening to your body after you receive the vaccine.

Episode Transcript

Interviewer: How many times have you heard from somebody, "You know, the only time I ever got the flu was the year I got the flu shot." Well, it's actually impossible, but what might be happening that would cause somebody to think that? We'll explore that next on The Scope.

Announcer: Medical news and research from University of Utah physicians and specialists you can use for a happier and healthier life. You're listening to The Scope.

Interviewer: Dr. Susan Terry is Executive Medical Director for the Community Clinics at University of Utah, and for the person that says that the only time that I got the flu was the year I got the flu shot, and that's their excuse for not getting the flu shot ever again. What would you say to that? First of all, is it possible to get the flu from the flu shot?

Dr. Terry: No. It's really not possible to get the flu from the flu shot.

Interviewer: All right. And why is that?

Dr. Terry: Because the virus that's in the flu shot is inactivated, and it's only there to help your body promote immunity. It's not really there to, in any way, make you sick.

Interviewer: So the fact that it's deactivated 100%, you cannot get the flu from the flu shot.

Dr. Terry: Correct.

Interviewer: All right. But yet there are some people that still say, "I got the flu shot and that was the year I got the flu." What might be going on there? Let's talk about the four possible reasons. Number one.

Dr. Terry: Sure. We know that it takes at least two weeks to become immune to the flu after you have your vaccination. So, you could pick up a virus in the meantime and come down with the flu.

Interviewer: All right. So you've got that two-week period there where you're kind of vulnerable.

Dr. Terry: Correct.

Interviewer: All right. The reason that somebody says that they got the flu after they got their flu shot number two.

Dr. Terry: We know that this time of year and any parent of school-age child will tell you, there are a lot of infections going around. We have the kids back in school. They're all together, and viruses of other kinds can spread like wildfire. And then, of course, they come home. So, you might feel really bad, and feel like you have the flu, but the likelihood that it is actually true influenza for which you have been vaccinated is pretty low.

Interviewer: So it's likely something else and you just you need to say it's the flu to feel better about the whole deal.

Dr. Terry: Right.

Interviewer: Okay. All right, reason why somebody might say they got the flu from the flu shot, number three.

Dr. Terry: You could be exposed to a flu virus that's not included in seasonal flu. We try to get as close as we can to what we expect to see in the influenza season, and it is a scientific process that's done, but we aren't always 100%.

Interviewer: So it's possible the flu you got was not accounted for in the shot.

Dr. Terry: Correct.

Interviewer: All right. And the reason somebody might think that they got the flu from the flu shot number four.

Dr. Terry: This is actually a little bit later on in the course in that some people just get infected with the flu virus after having a flu vaccine. Now, it is most likely to be the most protective for older children and younger healthy adults, but there are still people who have other types of illnesses or younger kids or older adults with chronic disease who, even though they are vaccinated and develop some immune response to the flu, can still come down with influenza.

Interviewer: And still can come down with one of the flu strains that they were... It's about 70% effective if I understand correctly.

Dr. Terry: That's right.

Interviewer: Yeah. All right. So, we've gone ahead and established that you cannot get the flu from the flu shot. People still deny that. Hopefully, we've given them some reasons why they might think that they got the flu from the flu shot, but bottom line is...

Dr. Terry: You won't get the flu from the flu shot. So, we strongly recommend that everyone over the age of six months gets a flu shot.

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