Actually, while I [i]did[/i] watch quite a bit of them just a little bit ago, I was referring to the far less laudable Gintama, which I still don't think deserves to be as good as it is. Based enough of Joe's personality on the protagonist that I am legitimately ashamed of myself. 

As for the other countries, they were definitely quarantining Italy, but there was no trace of the whole conspiracy side of it that they knew of. They just knew that some unidentified virus began to ravage the peninsula, and tried to stop it from spreading. Then, through unknown means (carefully targeted bioterrorism), it suddenly began to spread across the rest of the world ridiculously fast.