Think you got the flu from your flu shot? Think again.
That means you.
The flu vaccine is safe, even for pregnant women and people with chronic illnesses.
Can a flu shot give you the flu?
No. The flu shot can not cause the flu. The flu vaccine is made from either NO VIRUS AT ALL (recombinant vaccine) or from DEAD virus.
The recombinant vaccine is made without any flu virus at all. Manufacturers isolate certain proteins from the flu virus, and combine them with portions of another virus that doesn’t cause disease but that grows well and can replicate. This “recombinant” virus then grows and grows in insect cells, and the flu protein is then harvested and purified. When injected in you, this protein triggers an immune response, resulting in immunity to the flu virus.
The more common flu vaccine uses an inactivated, or dead, flu virus. The live flu virus is injected into either mammalian cells or hen’s eggs and allowed to grow and replicate. Once there’s enough, the virus is harvested in large amounts and killed, and the antigen (the protein in the virus that triggers an immune response in people) is purified out to make the flu shot.
The one exception to this is nasal spray flu vaccine, in which the flu virus isn’t killed. It’s just weakened (“attenuated”) to the point of not being able to cause illness. In addition, it’s cold-adapted, meaning that even if it could cause illness, it would only be able to so at cooler temperatures, not in the warm environment of human lungs.
What are the most common side effects of the flu vaccine?
The most common reactions from the flu shot are soreness, redness, tenderness or swelling where the shot was given. Low-grade fever, headache and muscle aches lasting a shot period of time (less than 2 days) can also occur.
There have been a few studies done looking at reactions to the flu shot. In one study, investigators gave some people flu shots, and other people salt water injections. The only difference was that the people who got the real flu shot had more soreness at the injection site. There were no differences at all as far as body aches, fever, cough, runny nose or sore throat.
So you can’t get the flu from the flu shot. The whole point of the flu shot is that you don’t get the flu, or if you do, that it’s a milder illness. Check out our pulmonary and critical care expert Dr. Robyn Scatena’s 4 Reasons to Get Vaccinated. Also take a look at this Screw the Flu video from Bellyblog.ca’s own Media Producer, Dr. Seema Marwaha, along with her op-ed piece on Healthy Debate about the recent ruling striking down the “vaccinate-or-mask” policy for nurses.