The following happened today while playing epidemic
After taking one card, the second card drawn resulted in an epidemic card.
So we tried to resolve it but the card we took from underneath the pile resulted in another epidemic card.
Epidemic cards are placed in the Player Deck (blue red white cards). You should be taking a card from underneath the pile of the Infection Deck (green black cards). The Infection Deck should not contain any epidemic cards.
mixed the whole discard pile (3 city cards and 2 epidemic cards), and put that on top of the draw pile.
Epidemics are removed from the game once they are played, they are not discarded into the Infection Discard Pile or the Player Discard Pile.
Hope this helps.