Also see Injured
Sickness can occur to anyone in the shelter that came back from an expedition without a Gas Mask (If the fallout outside is highly radiated), didn't get at least 1 soup serving every 7 days, or by certain events, (Such as the Suitcase event). People that are sick will eventually die/run away after 15/20 days. It can be cured by using a medkit or with the shower event. Feeding/giving water every day doesn't cure sickness. You can also tell if Ted or Timmy is closer to death when They're sick because their eyes will get more bloodshot, and he will appear to suffer more pain.
Gallery
A sick and tired Ted
A sick and tired Timmy
A sick,fatigued and crazy Ted
A sick and tired Dolores
A sick,crazy and tired Dolores
Ted Sick
A sick and tired Mary Jane
A sick,fatigued and Crazy Mary Jane