Knowing the origin of the flu viruses gives me respect for the fact that I'm under the weather in a different way than rhinoviruses would provide.
How to know? Google it.
If, like me, it's been 4 days with a fever, chances are very likely it's not the common cold.
And unlike the common cold, the incubation period for the flu isn't 48 hours, which means it can spread rather fast.
More on diseases and Buddhism to follow...