7. “Infected “
Season 4, episode 2
“Infected” launches a new enemy into the group: pandemic. Patrick dies from the flu and turns. D block is locked down for the night with everyone thinking that they are safe. Walker Patrick feasts on many of the people in the cell block, who then turn and continue ravaging the living.
After the group manages to stop the slaughter more and more them begin to come down with the flu-like symptoms that Patrick had. In conditions like that, it’s very easy for illness to spread, and it decimated the remaining survivors.
As the survivors try to manage the outbreak and bury the dead who were killed by Patrick and the other walkers Sasha notices that someone has been placing dead rats by the fence, which is causing the walkers to group up in clumps near the corner of the fence. This is a huge concern for the people assigned to clear the fences because it makes the fences very vulnerable.
At the end of the episode, Tyreese goes to see Karen, who is quarantined with the other sick people. He finds only a trail of blood that leads outside to the burned bodies of Karen and David.
There’s a feeling of nebulous menace throughout this episode that is practically palpable. The survivors have never dealt with an illness like this and they don’t have the medical supplies or the space necessary to deal with it effectively.