There used to be some anecdotal evidence presented that getting influenza or even common colds might ramp up the immune system to fight off serious diseases like cancer. I don't know though whether that has since been debunked or not. I honestly get a flu shot nowadays because it's included with my health insurance plan, it's the quadravalent vaccine, and it just might prevent me from being a flu virus carrier who infects others...a Typhoid Mary of sorts.
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