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A primary reason for needing a new vaccine for influenza each year is that there could be mutation of surface proteins leading to a new outbreak
<h3>What is antigenic drift?</h3>
Antigenic drift is a phenomenon that causes small changes or mutations in the genes of influenza viruses leading to changes in their surface proteins of the virus, which are HA (hemagglutinin) and NA (neuraminidase).
For this reason, new influenza vaccines are produced yearly to alter the effects that may emerge as a result.
Thus, a primary reason for needing a new vaccine for influenza each year is that there could be mutation of surface proteins leading to a new outbreak
Learn more about influenza here:
brainly.com/question/12975693
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That his body also is producing cortisol and if he stops they may be lower than usual or even adrenal insufficiency . also depressed immune system
