Which flu vaccine is best

It can take about two weeks after vaccination for antibodies to develop in the body, which is an important reason to get your flu vaccine early, before flu activity starts. Flu viruses can change from year to year, so the vaccine is updated to protect against new virus strains that are expected to circulate in the U. The vaccine needs to include influenza virus strains that most closely match those in circulation for the influenza season.

Typically, children and older people are most at risk of getting sick with influenza. The best way to protect babies who are too young to be vaccinated is to make sure people around them are vaccinated. Occasionally, a flu virus will circulate that disproportionately affects young and middle-age adults. The FDA has approved numerous vaccines for the prevention of influenza. But if you do get the flu, there are FDA-approved antiviral drugs, available by prescription, to treat your illness.

These drugs work best if started soon after the onset of symptoms within 48 hours. Following that process, the FDA convenes its vaccines advisory committee, consisting of outside experts, to discuss the WHO recommendations and to consider which flu viruses are expected to circulate in the U. The committee also reviews data about which flu viruses have caused illnesses in the past year, how the viruses are changing, and disease trends for the U.

Recombinant flu vaccines are produced using a method that does not require an egg-grown vaccine virus. To receive weekly email updates about Seasonal Flu, enter your email address:. Skip directly to site content Skip directly to page options Skip directly to A-Z link. Influenza Flu. Section Navigation. Facebook Twitter LinkedIn Syndicate. Different Types of Flu Vaccines.

Minus Related Pages. Find flu vaccines in your area. Below is a summary of the benefits of flu vaccination and selected scientific studies that support these benefits. Despite the many benefits offered by flu vaccination, only about half of Americans get an annual flu vaccine and flu continues to cause millions of illnesses, hundreds of thousands of hospitalizations and tens of thousands of deaths.

Many more people could be protected from flu if more people got vaccinated. Even if the effectiveness of the vaccine is reduced against one virus vaccination can still be effective at preventing flu illness caused by the other circulating viruses. For these reasons, CDC continues to recommend flu vaccination for everyone 6 months and older even if vaccine effectiveness against one or more viruses is reduced. Experts must pick which viruses to include in the vaccine many months in advance in order for vaccine to be produced and delivered on time.

For more information about the vaccine virus selection process visit Selecting the Viruses in the Influenza Flu Vaccine.

Because of these factors, there is always the possibility of a less than optimal match between circulating viruses and the viruses used to produce vaccine. The production process for some seasonal vaccines also may impact how well vaccine works against certain viruses, especially influenza A H3N2 viruses. Growth in eggs is part of the production process for many seasonal flu vaccines. While all influenza viruses undergo changes when they are grown in eggs, changes in influenza A H3N2 viruses are more likely to result in antigenic changes compared with changes in other influenza viruses.

Advances in vaccine production technologies for example, cell-based and recombinant technology and advanced molecular techniques are being explored as ways to improve flu vaccine effectiveness. Learn more by visiting, Advancements in Influenza Vaccines. A flu vaccine is made to protect against the flu viruses that research and surveillance indicate will likely be most common during the season. Over the course of flu season, CDC studies samples of circulating flu viruses to evaluate how close a match there is between viruses used to make the flu vaccine and circulating flu viruses.

More information about the flu season and recommended vaccines is available. No, a flu vaccine cannot cause flu illness. Flu vaccines that are given with a needle flu shots are currently made in two ways: the vaccine is made either with a flu vaccine viruses that have been killed inactivated and are therefore not infectious, or b with proteins from a flu virus which is the case for recombinant influenza vaccine.

Nasal spray vaccine is made with weakened attenuated live flu viruses, and also cannot cause flu illness. The weakened viruses are cold-adapted, which means they are designed to only reproduce at the cooler temperatures found within the nose. The viruses cannot reproduce in the lungs or other areas where warmer temperatures exist.

While a flu vaccine cannot give you flu illness, there are different side effects that may be associated with getting a flu shot or a nasal spray flu vaccine. These side effects are usually mild and short-lasting, especially when compared to symptoms of flu. A flu shot: The viruses in a flu shot are killed inactivated , so you cannot get flu from a flu shot.

Some minor side effects that may occur are:. The nasal spray: The viruses in the nasal spray vaccine are weakened and do not cause severe symptoms often associated with influenza illness. In children, side effects from the nasal spray may include:. If these problems occur, they begin soon after vaccination and usually are mild and short-lived.

A flu shot, like other injections, can occasionally cause fainting. Tell your provider if you feel dizzy or have vision changes or ringing in the ears. As with any medicine, there is a very remote chance of a vaccine causing a severe allergic reaction, other serious injury, or death. People who think that they have been injured by a flu vaccine can file a claim for compensation from the National Vaccine Injury Compensation Program VICP external icon.

More information about the safety of flu vaccines is available at Influenza Flu Vaccine Safety. Hibberd PL. Seasonal influenza vaccination in adults. Wilkinson K, et al. Efficacy and safety of high-dose influenza vaccine in elderly adults: A systematic review and meta-analysis. DiazGranados CA, et al. High-dose trivalent influenza vaccine compared to standard dose vaccine in elderly adults: Safety, immunogenicity and relative efficacy during the season. Efficacy of high-dose versus standard-dose influenza vaccine in older adults.

The New England Journal of Medicine. Grohskopf LA, et al. Prevention and control of seasonal influenza with vaccines: Recommendations of the Advisory Committee on Immunization Practices — United States, influenza season.

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