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A 28-year-old female asked:

Had flu shot in mid november -- tested positive for influenza a after a very mild illness. how did i get the flu? am 22 weeks pregnant.

2 doctor answers2 doctors weighed in
Dr. Timothy Brown
Obstetrics and Gynecology 41 years experience
Partially effective: The fact that the illness was mild reflects that the vaccine was not completely ineffective. The flu virus adapts year to year and the vaccine is modified to account for this, some years more effectively than others.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Glenn Messina
Aesthetic Medicine 36 years experience
Aprox 80% effective: First the flu shot takes 3 weeks to build full immunity so next year take it late october this way when the season starts ( nov in the ne) you are ready. Influenza affects about 20% of the population an the vaccine gives about 80% immunity if correctly paired to the current strain. In your case you did get flu but had some immunity since it was mild. Stay hydrated!
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Apr 22, 2014


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