First things first - the flu shot can't give you the flu.
It's an inactivated vaccine which means the virus is basically dead. We don't call it dead because technically we're not sure if viruses are actually alive in the first place, but that's a whole other thing. The nasal spray sometimes given to kids is a live vaccine, but even then the virus is weakened and should pose no risk for the vast majority of people.
Despite this, you'll probably see people claim they did get the flu from the shot. There are a few reasons for this.
Having the shot isn't a guarantee you won't get the flu, sadly. Because the flu virus mutates rapidly and the vaccine takes six months to manufacture we rely on predictions by the WHO of which strains will be most common. If a new strain appears, you won't be fully protected although there is evidence of partial protection for similar strains and that vaccinated people get over a bout of flu better than unvaccinated people. Also, the immunity takes two weeks to fully develop, so it's possible to get even the vaccinated strains in that time. That still doesn't mean the shot caused the illness, just that you were unlucky.
Also, because they're different viruses the flu shot won't protect you against getting a nasty cold which some people mistake for the flu.
The side effects are generally mild.
As with any vaccine there will be some side effects. Most commonly these are nothing worse than a sore arm and maybe some mild fever or aches for a day or two. Personally I didn't have any fever but did have a sore arm and a headache the next day, but that was easily solved with plenty of fluids and a couple of paracetamol.
Very rarely there may be a more severe reaction, but those are expected within minutes if they happen and shouldn't be too serious if treated quickly. If you're worried you can just sit for a while after the shot.
So, you might feel a bit less than 100%, but you probably won't need a round of "soft kitty". Unless you really want to milk it.
But really, why would I get the shot?
I may not be in a high-risk group myself, but I have friends and loved ones who are, so I got my shot to help protect them too. If I can reduce my risk of contracting the flu, I’m also reducing my risk of passing it on to others.
That means my dad, who is over 65 and suffers a chronic health condition, putting him in two risk groups. It means my friends with conditions like diabetes or asthma. It means my friends who are new or expecting parents - pregnant women and newborns are high-risk groups but if nothing else, a new parent really doesn't need a dose of the flu on top of everything else on their plate!
For people like me, the negatives of the shot are minimal — some time out of my day, a few bucks out of my pocket, and some mild side effects. The positives, however, are potentially far greater both for myself and for the people around me. I think any chance of avoiding passing on the flu is worth these minor downsides. The flu vaccine isn’t perfect, but it is an important tool and I think that just makes it more important to have the highest possible coverage.
What I do as an individual is one thing, but the more of us who get the flu shot the better. Every person who gains immunity is one less pathway for the virus to reach an at-risk person.
That’s why I got my flu shot, and I hope you’ll join me.
Adapted from my article "Why I got my flu shot".