I looked up the CDC timeline on it. It’s first case in America was on April 15th by June 25th at least 1 million people had the virus. I don’t remember it being that bad or getting bad that quick. That’s probably why the gov isn’t messing around with its warnings and drastic measures. Especially with 22k people had died from it.
https://www.cdc.gov/flu/pandemic-resources/2009-pandemic-timeline.html
https://www.cdc.gov/flu/pandemic-resources/2009-pandemic-timeline.html