[austinheap]

NIH/NIDA supports that number: https://d14rmgtrwzf5a.cloudfront.net/sites/default/files/cdc...

From 2001 to 2013 there was a 5-fold increase in the total number of deaths from heroin overdose.

Edit: I believe a 500% increase in overdose deaths qualifies under the 'epidemic' definition of "a sudden, widespread occurrence of a particular undesirable phenomenon."

[jnbiche]

So if there a rare disease increases 500% from a few to a few dozen, does that count as an outbreak?