Infant illness

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The Infant illness is a deadly disease that affects human babies on a sick birth.


Infant illness comes at 4 levels: mild, common, major, and grave, in order of severity. Mild infant illness will regress on its own, but a grave illness is nearly impossible to survive. Every 1-3 days, the illness will switch to a random phase.

The disease is cured once immune, or if severity falls to 0.


Infant illness can only be contracted at birth, and is dependent on its quality. Performing labor in a clean room, with a skilled doctor and loved ones, reduces the chance of being sick. Fostering an embryo in a growth vat acts as a natural birth with a quality of 70%. The storyteller setting, Babies always healthy prevents sick births from happening at all.


These are the following stages in which infant illness will progress through.

Stage Severity Symptoms
Infant illness (minor) 0 - 0.32
  • +5% Pain
  • Vomiting (MTB of 2.5 days)
Infant illness (major) 0.33 - 0.77
  • +8% Pain
  • Vomiting (MTB of 1 day)
Infant illness (extreme) 0.78 - 0.86
Infant illness (extreme) 0.87 - 0.99
Infant illness (extreme) 1.00


On a sick birth, infant illness will start with a severity of 0.40, or a major illness.

  • Severity increase depends on the severity of the disease. Without treatment:
    • Severity increase for mild infant illness is -0.25 per day.
    • Severity increase for common infant illness is 0.1 per day.
    • Severity increase for bad infant illness is 0.3 per day.
    • Severity increase for grave infant illness is 0.5 per day.
  • Every 1-3 days, the severity phase will change.
  • Immunity increases by 0.100 per day when sick, regardless of severity.
  • Treatment slows progression by -0.35 per day with 100% tend quality.
    • N.B. Tend quality above 100% has an impact on severity progression.

The disease resolves once immune, or when severity reaches 0.


As with any other disease: Make sure that the patient is rested, well-fed, and treated whenever possible. Even if it's currently mild, the illness can switch to grave at any moment. The best care will make the disease go away faster.

If you get a Grave infant illness multiple times in a row, there may be no saving the child. At 100% tend quality, a grave illness will progress by 0.15/day, enough to kill in 4 days. It takes an average of 126% tend quality, only achievable with glitterworld medicine in amazing setups, just to prevent death in 10 days. Due to the entirely random x0.8 - x1.2 InfectionLuck factor, this might not be enough to get immunity if the disease remains grave for its duration.


If there is no chance of saving the colonist with regular treatment, you can do the following:

  • Healer mech serum - instantly treats the disease
  • Become deathless - Becoming a Sanguophage, or implanting a xenogerm with the Deathless gene, will prevent the illness from actually being fatal. This gives the baby time to recover.
  • Unnatural healing - A creepjoiner's unnatural healing ability will instantly cure infant illness, however use of the ability is not with consequence - see its page for more details.

While luciferium increases Immunity Gain Speed, even this boost is not enough to save a child from an entirely grave infant illness, unless you have great doctors with glitterworld medicine already.

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