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view/download model file: vaccination_cycle.nlogo
The model simulates the transmission and diffusion of the influence's virus in a human population analizing in particular the cycle of the vaccine.
The duffusion of the virus works with the contagion between healthy peolple and sick people and with desease.
People (turtles) move ramdomly.
There are two kind of person:
- green colored : healthy people
- red colored : infected people.
If an healthy person, during his walking, contact an infected person he will get infected with a probability setted by the user through the slider prob_contagion.
A person own a defense of immunity that deecrease when temperature is under 17,5 degree (average temperature) and increase when is over this level.
When this defense reach zero the person get infect with a probability setted by the user through the slider prob_desease.
When a person get infect the next year he will vaccine with a probability 80%.This probability decrease progressively with the growth of the number of years that the person has been not infected.
There are two buttons that control execution of the model:
- SETUP will inizialize the simulation preparing the model to be run;
- GO is a forever button and will run the model.
Before clicking SETUP, set:
- NUMBER_OF_TURTLES, number of people in the world
- DURATION_OF_INFECTION, number of days of infection
- PROB_CONTAGION, probability of contagion
- %INFECT_INITIAL, percentage of infected in the beginig
- PROB_DESEASE, probability of desease
- YEAR_HEALTH_NO_VACCINE, number of years of health after that a person will not vaccine
- ZOOM change the temporal horizon of the plots
PANDEMIC? : it simulates the arrival of a new virus for which doesn't exist an effective vaccine yet
HOTBED? : it simulates the case in which the virus start its diffusion from a determined area (colored yellow)
They show the value of the variable assigned.
- PEOPLE, shows the course of the percentage of people healthy, infected and vaccined
- TEMPERATURE VS INFECTED, shows the course of temperature compared with the number of infected people.
If you change a parameter, plots could adjust in a interesting way so you can understand what would happen in a population when a virus starts his duffusion from a hotbed.
Try to introduced PANDEMIC? while the model is running.
The model can be applied also in other field (economics, social, political) for example in this way can be studied the diffusion of innovation in a society.