Shodor

This model represents the spread of a disease in a population. It is meant to illustrate the various factors that can affect how quickly and how far a disease can spread.

The people in this model can have various states representing their state. Here are the different states and the colors that indicate them:

Susceptible (Healthy) - Green

These people have not caught the disease yet and are susceptible to catch it.
They are in danger of catching the disease if they meet an infected person.

Infected - Red

These people are infected with the disease and are contagious.
They can pass the disease on if they meet a susceptible person.

Immune - Blue

These people cannot catch the disease. There are various reasons for an person to be immune:

• Recovered (plain blue): these people have caught the disease and recovered.
• Vaccinated (holding yellow shields): these people have been vaccinated by a doctor.
• Medicated (holding pill bottles): these people had the disease, but were treated by a doctor.

Doctors - White

Doctors are treated as immune to so that medical care will always be available to the population in the model. Doctors can give vaccinations and medication if the switches are turned on for those treatments.

How It Works

As the people interact, if a susceptible person meets an infected person, there is a certain chance (indicated by infectiousness ) that the disease will infect the susceptible person. Infected people can recover after a period of time (indicated by days-to-recover ). A portion of them (indicated by fatality-rate ) may die from the disease.

The hygiene slider causes the infectiousness of the disease to take less effect. It can be compared to attempts to contain the disease wearing masks, using proper sanitation, or washing hands. People still inadvertently catch the disease, but the disease spreads a lot slower.

In order to administer any treatments, you must add doctors before initializing the model. If vaccination is on, the doctors will vaccinate any susceptible people they encounter. If medication is on, the doctors will treat any infected people they encounter.

The limit-travel setting is meant to represent different countries or regions that may limit travel in an attempt to contain the disease. Less openings represent tighter regulations on travel.