Can influenza spread to other countries?
Quote from the wiki on this:
Option: This is not the first flu in our country, I don't care!:
The owner of the province: Changes administrative power stored by -5 Adds the modifier "Influenza" until the end of the campaign: province_trade_power_modifier = -1.0 -50% manpower modifier -50% provincial tax income -50% trade goods output
If: Limited to: Any bordering province: The province is owned by our country
Does not have the province modifier "Quarantined Influenza" Does not have the province modifier "Influenza" Randomized by Acquisition chance: Random bordering province:
Limited to: The province is owned by our country Does not have the province modifier "Quarantined Influenza" Does not have the province modifier "Influenza"
I have in the past chosen the "Don't care" option a couple of times and I can confirm that my flu has never crossed into another country.