Disease

Duplicants can become sick from diseases (caused by germs) and ill from other conditions (certain foods, stress etc).

## Germs

Diseases of Duplicants are caused by germs.

If a material/resource carries the qualifier "polluted" (dirt, water, oxygen) that means it is mixed with other resources but does not guarantee that it is contaminated with germs too! That means "polluted" items can be germ-free, but you will not know by hovering over it.

Slime is usually contaminated.

Germs multiply quickly as long as the conditions are right for them. Every machine/equipment/item/material has an upper limit of how many germs it can contain. That limit is multiplied by the mass of the item in case more than one unit exists.

## Infection & Spread

Germs can cover Duplicants (contaminated) and germs can be inside their body (infection). Every time a contaminated Duplicant interacts with another Duplicant or with a machine/equipment/building the germs will be spread accordingly. Climbing ladders is an interaction.

Only germs inside a Duplicant cause him to become sick. If a Duplicant is infected, his immunity starts dropping (according to rumors 1% for every 10,000 germs).

Infection occurs ONLY if the Duplicant breathes contaminated air in or eats contaminated food. That means a Duplicant can be contaminated and spread the germs but he is not infected.

Food CAN be contaminated (and then cause infection if eaten) if

* the harvester is contaminated
* the cook is contaminated
* the Duplicant eating the food has the status effect Dirty Hands or has the disease Trench Stench
* it comes in contact with polluted water, polluted dirt or polluted oxygen that contains germs
* it comes in contact with a slime or the solid tile next to a slime
* the water or ingredients used for preparing the food are contaminated

Microbe Musher do not eliminate germs when being used but the Electric Grill does.

Contamination on Duplicants CAN be indicated by the status Dirty Hands but this status does not always mean germs are present. Dirty Hands can be removed by wash basin and shower. The status effect Grimy does NOT mean the Duplicant is contaminated.

The atmosphere can be contaminated (and then cause infection if breathed in) if

* Polluted oxygen is present
* the atmosphere is exposed to polluted water or polluted dirt, which release polluted oxygen
* a Duplicant with Slimelung coughs into it
* a Duplicant with The Spores breathes into it

## Treatment of Duplicants

If a Duplicant is assigned to a medical bed they receive treatment by that bed.

Other Duplicants can improve the treatment by providing medical aid - which is a job that uses the Aid attribute.

## Preventing and Fighting Disease

### Keeping Immunity High

There are several ways of preventing the Duplicants getting infected and sick:

* low stress
* good food
* good hygiene
* enough sleep
* a clean environment

### Preventing Germs from multiplying

A clean environment is achieved by

* careful design of the ventilation system to prevent Duplicants being exposed to polluted oxygen
* ensuring enough outhouses/lavatories are available and they are emptied accordingly
* keeping Slime and Puft enclosed and away from your Duplicants as much as possible
* Removing polluted water by plumbing or mopping and composting polluted dirt carefully
* monitoring the contamination situation screen of your colony regularly (sometimes Duplicants can drag germs in!) by opening the "Germ Overlay".

### Disinfecting Contaminated Areas/Items

Germs die off rather quickly if the conditions are not favorable for them. Chlorine for example disinfects slimes that were contaminated.

Germs will NOT move from a liquid to a gas or solid and they will not move from solid tile to another solid tile. Slimes are the only exception, they will infect the tile they sit on and the solid tiles adjacent to it.

If a raw material or food is contaminated then processing it will usually NOT remove the contamination. The resulting product will be contaminated the same way. If contaminated but otherwise pure water is processed by an Electrolyzer then contaminated oxygen and hydrogen will result. But the germs will die very quickly in the latter two as they need the pollution.

In summary these are ways of removing contaminating germs from material/items:

* cooling a gas below condensation temperature - the gaseous fraction will still be contaminated but the liquid fraction will be clean (if not mixed with contaminated liquid)
* heating a liquid above its evaporation point so it turns into a gas - if the gas is not mixed with a contaminated other gas
* removing the pollution from the material the germ inhabits as long as it is not food: generating pure oxygen, dirt or water from polluted versions. They can still be contaminated with germs but the germs will die off rather soon as they need the "polluted" component to survive
* exposing the material or item to a disinfectant (e.g. place a storage locker with the material in a room filled with Chlorine gas or adding a Bleach Stone on top that leaks Chlorine)
* Duplicants performing the automatic chore "Disinfection"