Infection
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 1.19 days from contraction if it isn't on any vital parts.
Good treatment will slow the disease to the point where it takes 3.22 days to kill, and treatment on wounds reduces the chance of a wound infection.
It takes around 1.55 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 50.
This disease is unique in that 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.
Mechanism
When a colonist has an infectable wound the game will count down randomly from 15,000 ticks (4.17 mins) to 45,000 ticks (12.5 mins). 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
- +5% Pain
Major - Severity: 0.33 - 0.77
- +8% Pain
Extreme (Initial) - Severity: 0.78 - 0.86
- +12% Pain
- -5% Consciousness
Extreme (Advanced) - Severity: 0.87 - 0.99
- 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 0.6441 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
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 a worthy precaution to take.
Treatment
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.
Normal People
For colonists with 100% immunity gain speed, you will need at least 29% average treatment quality to ensure that one doesn't succumb to their infected wound(s).
Extremely vulnerable
For those with a base immunity gain rate of 43% or less, there is no chance that they will be able to survive a wound infection normally, even with 100% treatment quality for all treatments and rest in a hospital bed with vitals monitor connected. This includes old people at age 120 or above, and some people with kidney and liver damage (physical or chemical).
To save the colonist you can do the following:
- Administer healer mech serum- instantly treats the infection
- Administer luciferium- if pawn has 25% or more immunity gain speed remaining initially, this gives pawn a chance to survive
- Amputation
- Part replacement
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.
Version history
At around Beta 18 infections caused a reduction in part efficiency, allowing them to kill much earlier than usual if a critically injured vital body part is infected and the infection causes the efficiency of that body part to drop below zero.