Maybe Margie was homeschooled. Otherwise she would have learned about how 3 out of 4 contagious diseases are Zoonotic Diseases, or those that cross over from animals to humans. The mutation rate among diseases, especially like Covid-19 or even the common flu, can be so fast that they require updated vaccinations.
For a short primer, go here. For a longer one, get a fucking degree.
Or go ahead and fall for fear-peddling MTG and her ignorant-laden rants. Goddamn, she’s dumb.