Cliché but essential disclaimer that I’m not a doctor.

It seems that there are two main camps when it comes to the flu shot.

1. Either you believe that the flu shot absolutely causes the flu and you should never take it, or…
2. You believe it’s actually impossible to get sick from the flu shot, and that anyone who disagrees is a conspiracy theorist.

But the truth avoids both of these simple narratives.

Keep in mind that one doctor does not make data.

What follows is my own logic on the situation, and while I did ask my doctor—who agreed with me—one doctor does not make data. You should ask yours as well.

When we pretend the shot doesn’t make some people feel sick, we open the door to people claiming it gives you the actual flu .

Here’s the logic flow:

Nasal spray versions can contain weakened virus, but not shots. SOURCE

1. The flu shot does not contain live virus so it’s not capable of actually giving you the flu. SOURCE
2. The shot works by stimulating the immune system, so when someone gets it there’s an immune response that can actually make you sick for a day or two, which is not the flu.
3. Because of the massive number of people in the country, combined with how many were already getting the flu when they took the shot, some percentage of people will end up with the flu right after they get the shot—and will then believe the shot was the cause.

Think about how those three facts combine in situations where hundreds of thousands of people are getting sick, getting the vaccine, and getting the flu all at once. Given those numbers, there’s simply no question that many, many people have gotten the flu right after getting the shot. Period. It’s just a matter of probability.

Some people report having mild side effects after flu vaccination. The most common side effects from flu shots are soreness, redness, tenderness or swelling where the shot was given. Low-grade fever, headache and muscle aches also may occur. If these reactions occur, they usually begin soon after vaccination and last 1-2 days.

CDC Website

CDC Website

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Does that mean the shot caused the flu? No.

Some of those people get the flu right after (because they were already going to get it anyway), and some get better immediately and develop the resistance to flu.

Ok, so…where does that leave us?

1. The flu shot can’t directly give you flu because it doesn’t use live virus.
2. The shot can make you feel bad, however, because your immune system is under a temporary load after you get it.
3. Some people who take the flu shot were about to get it anyway, and since it takes a couple of weeks for immunity to build up, there was no time for the shot to protect you.

This simple set of three facts explains pretty much every situation we hear being debated on social media about the flu vaccine.

It explains people who’ve felt bad afterward (including me). It explains the people who’ve gotten the flu right after taking it (surely quite a few). And it explains the data showing the shot absolutely helps overall.

It also explains all these things in a way that acknowledges people who’ve actually gotten sick from the shot—or even gotten the flu after it—rather than dismissing them as crazy or stupid.

Summary

1. The flu shot doesn’t contain live virus.
2. The shot does kick your immune system in the face, so it might make you feel like crap.
3. If you were getting the flu beforehand you might still get it after, but it won’t be because of the shot.
4. If you can, try to get the shot when you’re healthy in order to avoid additional load on your immune system.

Don’t wait until everyone around you has the flu and you’re starting to feel bad. Because if you do, you might actually get the flu right after—because you were going to anyway—and then you’ll be another person the internet talking about how the flu shot gave you the flu.

Notes

1. I saw a funny joke about this topic on Reddit the other day. Someone said they got the flu from the flu shot and a commenter said, “Well sounds like you got the flu shot instead of the flu vaccine shot!”. That was funny.
2. I’ve gotten sick from a flu shot a couple of times, but I’ve never gotten the flu from it. It was just a couple of days of blah—-as if someone kicked my immune system in the solar plexus.
3. This piece here is an exercise in logic, and I encourage you to take it to as many doctor friends you can find. I’m curious what they think of it. I’ve only asked a few, but they said this was fully in agreement with both their training and their experience in the field.