Avian flu is often spread among migratory birds as they share the same ecosystems and breed across disparate places.

Birds outnumber humans by the millions, so it is no surprise that avian flu has been transmitted to human populations—

mostly by proximity to their feces.

Sometimes avian flu can be deadly, but most of the time it’s just a common flu virus—

a cold that is annoying at first,

but you become immune to it in the end.