Zombie Flu

The so-called Zombie Flu is a disease that the Cats end up getting in the episode "One Flu Over the Cat House".

Appearance
When it infects any animal they become really sick with greenish yellow eyes and a bit of messy fur. While it can happen in real life when humans gets sick, here when an animal (any species) gets sick, it makes them act like zombies, probably because of how terrible it is.

Background
The Zombie Flu started off with Penelope getting it, then her flu spreads onto Mela, Chi, and Marie. However, Oliver, Mimi, Susu, Lulu, Doom Kitty, and Sagwa hide in Sagwa's room to avoid the flu. Afterwards, Lulu gets it with no explanation, gets kick out, and is now one of the sick kitty sisters. So later on, the remaining cats use Sagwa's water guns, filled with chicken noodle soup to beat the cat sisters who got sick, so that they could escape the house, before getting infected. However, Susu gets corned, and gets coughed on making her infected and now having the flu, leaving only Oliver, Mimi, Doom Kitty, and Sagwa left. While downstairs Duchess, Thomas O'Malley, and the pets get infected as well. Afterwards, they get back upstairs, Pussyfoot is also infected, and she has followed them into Sagwa's room, and sneezes out a snot bubble, which flew out the window. They decided to use Pua's pig door to escape, but then the snot bubble came back, it hit Doom Kitty, and infected her, and then Sagwa gets infected, after Doom Kitty sneezed on her, now leaving only Oliver and Mimi left. Susu sneezes out mucus which was flying toward Mimi, and then Oliver jumps in, blocks Mimi, and he gets Susu's mucus on him. Mimi was glad that Oliver saved her, but then Oliver sneezes on Mimi, and now both of them are infected, leading to no survivors, and now everyone in the house is infected. At the end, Patch came in, and fed the cats his Santa Fe' egg rolls, so that it could help them get better later on.

It's unknown if this is the only time the Zombie Flu has occurred, or if it might happen again in a later episode.

Victims (in order)

 * Penelope Pussycat (patient zero)
 * Mela
 * Chi
 * Marie
 * Lulu Caty
 * Susu Caty
 * Pua, Meeko, Pascal, and Hei Hei (although the pets probably got it somewhere between when Thomas O'Malley and Chi got it)
 * Thomas O'Malley (although probably got it somewhere between when Duchess and Mela got it)
 * Duchess (although probably got it somewhere between when Penelope and Mela got it)
 * Pussyfoot (although probably got it somewhere between when the pets, Chi, and Marie got it)
 * Doom Kitty
 * Sagwa Miao
 * Oliver
 * Mimi Caty

Trivia

 * This is the first disease to happen on the show.
 * While it has only happened once in the series so far, Marie was seen having yellow eyes again in "Patching Things Up" and "Kitty's Paradise", which both could be a reference to Marie getting the Zombie Flu in "One Flu Over The Cat House".
 * Pua, Meeko, Pascal, and Hei Hei are the only animals who got sick with the flu that are not cats.
 * When Thomas O'Malley got the flu, his eyes became dark yellow due to his eyes usually already being yellow.
 * Pascal is the only one when infected to only just get yellow eyes since he has no fur or feathers.
 * Rufus and Pom Pom are the only cats of the Cat family who did not get infected by the zombie flu. Mainly because they live far away from the Cat House in separate houses.
 * Squibbon is the only Cat House pet that did not get the zombie flu.
 * It's unknown how long the flu lasted for The Cat Family, but it probably lasted one week for them, and then they all got back to normal health afterwards after the events of the episode.
 * Patch is the only main character of the show that did not get infected.