The flu shot is the best protection against seasonal flu.
This is why millions of people get the influenza vaccine each year.
According to the World Health Organization, the seasonal flu infects up to 1 billion people annually.
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Common Side Effects
Flu shots are produced by using inactive viruses.
This means they have been killed and are not infectious.
An annual flu shot offers safe and effective protection against the seasonal flu.
The side effects are typically mild.
They are triggered by theimmune responsethat boosts your immunity to the virus.
How long do you feel bad after the flu shot?
Side effects may include:
Does the seasonal flu vaccine affect your heart?
In a positive way, yes.
Rare Side Effects
In very rare cases, people may have seriousallergic reactionsincludinganaphylaxisafter getting the vaccine.
Signs of anaphylaxis include:
Anaphylaxis is a medical emergency.
This severe reaction typically occurs within five to 30 minutes of contact with an allergy-causing substance (allergen).
In some cases, symptoms may appear more than an hour later.
The rate was 1.5 cases per million doses for a typical influenza vaccine.
Egg Allergies
For many years, people with egg allergies avoided flu shots.
This is because the vaccine was initially produced using chicken eggs, posing a potential risk for a reaction.
Newrecombinantor cell culture-based flu vaccines are made without eggs, making them safe for people with egg allergies.
You should tell your healthcare provider if you have anegg allergybefore getting the flu shot.
Still, it’s important to know that this should not prevent you from getting the vaccine.
The risk of an allergic response toanyflu vaccine is extremely low.
This includes vaccines that are egg-based.
The provider can watch them for signs of a reaction and manage the symptoms quickly.
However, they are at no greater risk for side effects from a flu shot.
Flu vaccines have been proven safe in this vulnerable population of people.
On the other hand, the FluMist nasal spray vaccine isnotrecommended for people with certain chronic health conditions.
This is due to possible complications from the weakened form of the live influenza virus it contains.
FluMist Side Effects
The FluMist nasal spray is a live attenuated influenza vaccine (LAIV).
This means it is made withlive viruses that have been weakened.
They are unable to causeinfluenza illness.
These weakened viruses can only multiply at cooler temperatures, like those found in the nose.
They cannot survive at normal body temperature.
Do you shed the flu virus after getting the vaccine?
Vaccines and Autism
For years, there have been rumors to suggest the flu vaccine may causeautism.
One of the claims is that preservatives such asthimerosalare a possible trigger for autism.
Research has shown thatthis is not the case.
According to the CDC, thimerosal has a long history of safety.
There is no evidence of harm resulting from the low doses used in vaccines.
If you are concerned about preservatives in the flu vaccine, talk to your healthcare provider about other options.
Most single-dose vials and prefilled syringes do not contain a preservative.
This is because the products are used right away and not shared.
The same applies to the FluMist nasal vaccine, which is also preservative-free.
Summary
An annual flu vaccine is safe and effective for preventing influenza.
They typically go away in a day or two.
Some people with allergies, notably to eggs, need to be aware of the possibility of a reaction.
Recombinant vaccines are an option because they are produced differently.
People who have had a severe reaction to the flu vaccine should not receive it again.
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Centers for Disease Control and Prevention.Flu and people with diabetes.
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