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How long do you think is a flu shot good for?

1 doctor weighed in
Dr. James Ferguson
Pediatrics

In brief: Define "good"

The flu strains mutate often & each year the predominant strains change.
The flu vaccine is developed yearly using 3 strains that are circulating & already causing "flu" in so many places that a they are expected to continue.The vaccine stimulate production of antibodies to the included strains that last for years. But the flu mutates so often, last years vaccine is unlikely to stop this years flu.

In brief: Define "good"

The flu strains mutate often & each year the predominant strains change.
The flu vaccine is developed yearly using 3 strains that are circulating & already causing "flu" in so many places that a they are expected to continue.The vaccine stimulate production of antibodies to the included strains that last for years. But the flu mutates so often, last years vaccine is unlikely to stop this years flu.
Dr. James Ferguson
Dr. James Ferguson
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