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How long before a flu shot is effective

A 32-year-old member asked:
Dr. Scott J. Wolfson
Pediatrics 22 years experience
It's about strains: The flu vaccine is likely to have protective benefits everywhere. Even if strains are different in different world regions, there should be enough cro... Read More

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A 39-year-old member asked:
Dr. Anatoly Belilovsky
Pediatrics 35 years experience
Depends.: It should work in the same season in the same (northern vs southern) hemisphere, but crossing the equator might put you in a different epidemic situat... Read More
A 45-year-old member asked:
Dr. Robert Kwok
Pediatrics 33 years experience
Same effectiveness: A flu shot or flu mist are both just as effective. The flu mist has some age restrictions, and persons with some medical conditions (such as ongoing a... Read More
Dr. Heidi Fowler
Psychiatry 25 years experience
Shot vs mist: This year at least one organization is recommending the Flu Shot over FluMist. See: https://www.unitypoint.org/livewell/article.aspx?id=a9b8e576-4... Read More
A 45-year-old member asked:
Dr. Heidi Fowler
Psychiatry 25 years experience
Strongly recommend: Annual influenza vaccine. I can't tell you how effective it is. Even if you do catch the flu (and have been vaccinated) it is likely to be less aggres... Read More
A 37-year-old member asked:
Dr. Heidi Fowler
Psychiatry 25 years experience
Influenza Vaccine.: There is a lot of variability in how effective flu vaccines are from season to season. This is impacted by how well the influenza vaccine is matched t... Read More
A 33-year-old member asked:
Dr. James Ferguson
Pediatrics 46 years experience
Define effective: The flu strains mutate often. Each year the predominant strains change. The flu vaccine is developed yearly using 3 strains that are circulating and a... Read More
A member asked:
Dr. Martin Raff
Infectious Disease 56 years experience
Depends: The antibody produced may last a very long time, but the particular strain of influenza encountered may have changed so that those antibodies are not ... Read More
A 45-year-old female asked:
Dr. James Ferguson
Pediatrics 46 years experience
Too early to tell: So far the flu activity has been spotty. It will be well into the holiday season & related gatherings of folks from all parts of the country that we ... Read More
A 26-year-old female asked:
Dr. Luis Villaplana
Internal Medicine 35 years experience
Hands off face!: There are several things you can do. The predominant strain this year spreads like wild fire. At the end of this season, we may see a record number o... Read More
A 39-year-old female asked:
Dr. Silviu Pasniciuc
Internal Medicine 27 years experience
Flu season: We are not going to know until the season is over. The vaccine is usually prepared on a prediction and awareness and timely assessment and treatment r... Read More

90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more. Get help now:

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