Flu season semantics

As autumn becomes winter in the Southern hemisphere, the air dries up and our collective nasal mucus cakes down: It’s the start-gun for the doorway to the influenza virus to open, with the main event in this pill-popping Orthomyxoviridae Office Olympics being the all-out virion round-robin, played strictly indoors in these fancy airtight 21st-century Corporate high-rises where the hazmat baton is passed from cog to cough, then from cough to cog, swirling around and about the climate-controlled ether of the fiber-optics carpeted sprawl then in & out & through the water bags in suits & ties...

It’s the same thing, really, year in and year out.
With me it always begins with a sore throat: Whenever my throat dries up and starts to hurt, and we haven’t really seen the rain in weeks, damn if it isn’t a cold coming...
And hey, it’s arrived or what…

Now my question it’s a bit academic. As in scientific.
For instance, the cold-weather flu outbreak is like a minor epidemic, right? I mean, it’s epidemic because it affects a given population hitherto unaffected and is transmitted within this population, etc… but considering every autumn-winter we all get this lousy at the office with out red eyes and sore throats and dripping noses and so on- I mean, isn’t cold-season flu sort of endemic to the really-big metropolises in this day & age?
I mean, God, it’s a given you’re coming up with the flu too whenever the people sitting around you begin sneezing…