Sickness - GarwelGarwel/KerbalHealth GitHub Wiki

This section needs to be updated for Kerbal Health 1.3

Kerbals can now have infectious diseases. The life cycle of such a sickness is as follows:

  1. OK. The kerbal is healthy, but vulnerable to an infection.

  2. Incubation period. A kerbal can catch a sickness either at KSC (where they live their normal lives) or on a mission from a sick or infected crew mate. By default, the kerbal has a 0.5% daily chance to catch something at KSC and a 5% daily chance to be infected by another kerbal (the more infected kerbals around, the greater the chance). This health condition is not displayed and has no immediate effects on the kerbal's health, except that other kerbals can become infected. It usually lasts around 20 days.

  3. Sickness. The disease shows signs and the kerbal starts losing health (at 2 HP/day). Mobile Processing Lab can help lower the effect of a sickness by 50%, but it still puts any long-term mission at serious risk. The disease may cure on its own (with a chance of 5% per day), but the chances are much better if you have Scientists or Medics on board (adding a 10% chance per day). Note that if you have more sick kerbals than doctors, this effect will be reduced.

  4. Immunity. If your kerbal has successfully fought off the disease, either by him/herself or with the help of medical magic, they gain temporary immunity and will not catch the disease again for some time (around 20 days on average). Then everything goes back to step 1.

To minimize your risks, you naturally shouldn't send sick kerbals on missions, especially with more crewmates. Still, an infected kerbal can unwittingly smuggle the bad microbes on the ship and cause an epidemic. To fight that, make sure you have scientists and/or medics on board.