According to the Centers for Disease Control (CDC) you can’t contract the flu from a flu shot, but some people experience certain flu-like side effects. Flu shot reactions can range from nothing to worry about to allergic reactions that may require a doctor’s care.
You can prepare yourself for possible side effects by knowing what to watch for and which reactions might be cause for concern.
9. Why Your Symptoms Aren’t the Flu
Dr. Andrew Pekosz Ph.D., professor of molecular microbiology and immunology at Johns Hopkins University Bloomberg School of Public Health, told Men’s Health it’s not actually possible to catch the flu from the flu shot.
“The flu shot is a killed flu virus that consists of only half of the virus—the part you need to make an immune response to,” Dr. Pekosz said. “It’s also then administered into your arm muscle, which is not a place the flu virus normally goes to. So there is no possibility you can get the flu from the flu shot.”
8. Common Flu Shot Reactions
The following side effects are common and temporary after receiving a flu shot. They are usually nothing of concern, and are signs of the immune system doing its job.
- Soreness, discomfort, redness and swelling at the site of the flu shot
- Sore muscles
The CDC states that these symptoms are usually mild and end within a few days. They also claim that fainting occasionally occurs after receiving a flu shot, which can happen with other types of injections as well.