An annual flu shot offers you the best protection against the influenza virus and is recommended for most individuals 6 months and older. It is still possible for you to get sick after a flu shot, but this isn't because of what's in the shot. The flu vaccine is made from killed, or inactivated, viruses that can't give you the flu. Show This article explores the reasons why you may get sick after the flu shot. It will also explain how the vaccine may help reduce symptoms and complications if you do end up getting the flu. Verywell / Joshua Seong Why Can You Still Get the Flu After a Flu Shot? There are many reasons why you may still get sick after getting the flu shot. How effective it is will depend on several factors including the timing of the shot, as well as your body's immune response. You Haven't Built Up Immunity YetIt takes two weeks to build up your immunity to influenza after you get the shot. Immunity is how well your body is able to fight off illnesses. If you get the flu within two weeks of getting the shot, you were probably exposed to the virus around the time you got your vaccine. You Have A Different IllnessThe flu shot does not protect against these flu-like illnesses:
Each of these illnesses can cause symptoms that may be confused with the flu. The Correct Strain of Flu Isn't in the VaccineThe flu shot provides protection against three or four specific strains, or types, of influenza. These strains are selected by researchers who hope to protect as many people as possible. Because the flu virus mutates, or changes, new vaccines have to be made every flu season. Despite their best educated guesses, researchers and public health officials may get it wrong. If that year's illness-causing strains of influenza are not included in the vaccine, people who get the flu shot may still get the flu. You Didn't Respond Fully to the VaccineYour immune system may not respond fully to the vaccine and you may still get the flu if:
Even if you don't respond fully to the vaccine, you are still less likely to have serious complications from the flu. This is especially important for children and older adults who are at the highest risk of experiencing serious flu complications. Research shows that the majority of people who are vaccinated against the flu have significantly less severe symptoms and complications when they get sick than those who are unvaccinated. You're Over the Age of 65Anyone over the age of 65 is considered high risk for the flu and associated complications. This means that the flu is more likely to lead to very serious illnesses and even death in this age group. Despite the fact that older individuals' immune systems may not respond fully to the vaccine, it is still recommended that they get vaccinated every year. Studies show that individuals age 65 and older who got the flu shot:
SummaryDespite getting the annual flu shot, it is still possible to get sick. Reasons you may get sick include:
Vaccinated individuals who do get sick typically have less severe symptoms and complications. This is especially important to keep in mind for high risk groups such as individuals 65 and older, as well as children. A Word From VerywellIt can be frustrating to get sick after getting your flu shot. Keep in mind that those who are vaccinated and do get the flu tend to experience milder symptoms, as well as reduced complications. Even if you get the flu, it's still a good idea to continue getting your annual flu shot. By Kristina Duda, RN Thanks for your feedback! |