Infection

From RimWorld Wiki
Jump to: navigation, search


Overview

Infections can occur on most wounds, except missing body parts or blunt trauma. Infections are the fastest working illness in RimWorld, taking little more than a day to kill the victim if left untended. Animals can also contract infections at a reduced rate.

General symptoms include a small amount of pain and partial loss of part function. Advanced symptoms include a small-moderate amount of pain, slight loss of consciousness and further loss of part efficiency, and shortly after: a loss of consciousness, an excruciating amount of pain, and acute part failure, along with a slight loss of breathing. Death follows not long after.

If left untreated, infections can kill in 1.190 days from contraction if it isn't on any vital parts.
Good treatment will slow the disease to the point where it takes 3.226 days to kill, and treatment on wounds reduces the chance of a wound infection.

It takes around 1.515 days to develop immunity to an infection, assuming the affected colonist is rested in an ordinary bed for the whole time, has normal blood filtration, is well-fed, and under the age of 40.

Due to the reduction in part efficiency, if it causes the efficiency of a vital part to reach 0%, the pawn will die instantly. This is a surprisingly common cause of early-game death when the quality of healthcare is insufficient to slow the disease sufficiently for the immune system to catch up, before it disables the affected part completely resulting in certain death. However, if any other part reaches 0% efficiency, the part is not destroyed and can make a full recovery.
Rarely, colonists with a critically damaged vital part (<10% efficiency) will instantly die upon contracting an infection, with it reducing the efficiency below 0% at its start.

Colonist died before infection reaches 100% due to 0% torso efficiency. This situation is frequently encountered after battles when colonists receive heavy damage to the torso (sometimes head or neck) and receive an infection there, but lack adequate healthcare.


This disease is unique in several aspects.

  • It only affects a specific body part, making infections curable by amputating the affected body part. It is not possible to amputate vital body parts.
  • It is visible immediately when contracted.

Mechanism

When a colonist has an infectable wound the game will count down randomly from 15,000 ticks (250 secs) to 45,000 ticks (750 secs). Once it reaches this timer it will decide if the wound will be infected.

The chance of a pawn getting an infection depends on the tend quality, wound type, room cleanliness, and storyteller difficulty.

  • Treated wounds can still get infected at a reduced chance.
    • The chance multiplier is 85% at 0% tend quality, and linearly decreases to 5% at 100% tend quality.
  • Different wound types have different chances to get infected.
    • Bite, burn or frostbite wounds have a 25% chance.
    • Most other bleeding wounds have a 10% chance.
    • Bruises, cracks or missing parts cannot be infected.
  • Clean rooms with sterile tiles have a 32% chance multiplier. In contrast, a regular room without any dirt has 50%, and outdoors spaces have 100%.
  • Colonists are more likely to get wound infections at higher difficulties.

Animals have 20% of a colonist's chance to get an infection.

It is possible to have multiple infections simultaneously across different body parts. Each infection progresses at its own rate, while immunity against infections progresses at the same rate across the whole body.

Stages

Minor - Severity: 0 - 0.32

  • -10% Part efficiency
  • +5% Pain

Major - Severity: 0.33 - 0.77

  • -30% Part efficiency
  • +8% Pain

Extreme (Initial) - Severity: 0.78 - 0.86

  • -50% Part efficiency
  • +12% Pain
  • -5% Consciousness

Extreme (Advanced) - Severity: 0.87 - 0.99

  • -70% Part efficiency
  • Loss of Consciousness (max 10%)
  • +85% Pain
  • -5% Breathing

Extreme (Fatal) - Severity: 1

  • Death

Progression

  • When not immune, severity increases by 0.84 per day.
  • When immune, severity decreases by 0.7 per day.
  • Immunity increases by 0.66 per day when sick.
  • Treatment slows progression by a maximum of 0.53 per day.
    • This means that the disease will progress by 0.31 per day at this rate.

Prevention and Treatment

In order to prevent infections, make sure that people and animals that have open wounds are in a clean room when treated in the first place (e.g. no natural flooring apart from rock, no dirt or blood left to stay in the room, etc.). Although a clean room (or indeed sterile) won't fully nullify the chances of a wound getting infected, it will reduce the chance of an infection occurring - and is therefore a worthy precaution to take.

As with any other disease: Make sure that the patient is rested, well-fed, and treated whenever possible. Infections progress very quickly, and missing a treatment can be a very costly mistake. Due to the rate at which they progress, you'll need at least a competent doctor and medicine in order to ensure that the affected person survives their infections.

As a last ditch, if a colonist is about to die, don't hesitate to amputate the affected part. It's better to have a colonist missing a part or two than a dead one, and they won't mind if you remove their infected parts, either.

Pawns with critically damaged and infected vital parts will need rest immediately at beds and receive the best healthcare available, to slow the disease down. Infections on that part kill much earlier than they usually do.

Treating Normal People (<40 Years Old)

You will need at least 35% average treatment quality to ensure that one doesn't succumb to their infected wound(s).

The following combinations of medicine skill and medicine type are capable of delivering 35% treatment quality, but you'll want to aim higher than this as these combinations are the bare minimum, and aren't guaranteed to work out in your favor (they don't take the doctor's journey or time to administer into account):

Treating the Elderly (80+ Years Old)

As usual, older colonists will have weaker immune systems and that translates to a 20% loss in Immunity Gain Speed. You should therefore execute heightened medical protocols to ensure that elderly people with infected wounds make it through the painful process.

To successfully treat an elderly colonist with an infected wound, they'll need to get at least 60% treatment quality on average for their infection. The following list again states the minimum combinations required to achieve this standard of treatment, but you should generally aim higher than these:

  • Level 2 Medicine skill and Glitterworld medicine
  • Level 7 Medicine skill and ordinary Medicine
  • Level 13 Medicine skill and Herbal medicine

Amputation

If you know that a colonist might not make it, it's best that you amputate the part. Colonists that reach 80-90% disease progression with their immune systems unable to catch up should have their infected part amputated immediately if possible.

There is a chance that an amputation will fail, however, if not amputating will result in certain death it is best to take the risk. Besides, if you are amputating a hand, what does it matter if the surgeon manages to tear off the rest of the amputee's arm?

If the infection has progressed to over 97%, there is little to no chance your surgeons can successfully pull off an amputation in time. It's better to strip the sick colonist of their clothes and leave them to die (or euthanize them to make their imminent death less painful).

Part replacement

Besides amputation, you can also swap out the diseased part with a healthy one. If the surgery fails, however, you will risk another infection from the surgical cuts and stabs.