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Here is a village somewhere in the world sometime near the end of the 1800's. Epidemics break out, and scientists like Charles Louis Alphonse Laveran, Ronald Ross, Carlos Finlay, and Walter Reed are trying to determine their cause. In this model, the disease may be spread
(1) By direct contact with infected humans.
(2) By drinking infected water.
(3) By eating tainted food.
(4) By being bitten by flying insects like mosquitos.
For simplicity, we have omitted the possible vectors of breathing airborne infectious agents, being bitten by crawling insects like ticks, and living in an unsanitary situation.
Enter a 5-digit numerical key. Set up and run the simulation repeatedly varying whether or not you reduce the mosquito population, supplement the villagers' food supply with sterile meals, or supplement the villagers' water supply with sterile water. Can you determine which of the 4 possible sources are responsible for the epidemic associated with that numerical key.
In the simulation, the human inhabitants of the village sleep for 8 hours in their houses, after which they make their way to the river for water, eat 3 times a day (food not shown), and wander about doing their daily activities. All the while, black mosquitos are flying around, including in and out of the houses.
Something infects an uninfected individual, but they don't become symptomatic for 24 hours, on average. When they do become symptomatic, they head for the hospital. The hospital houses the symptomatic until they recover 72 hours, on average, after becoming symptomatic.
The plot counts ONLY those who are in the hospital -- others may be ill and simply have not yet gone to the hospital.
1. Enter a 5 digit number (and hit the enter key after doing so). This will generate an epidemic with one of the 7 sources above (and same epidemic for each 5 digit key).
2. Press the SETUP button.
3. Press the GO button to begin the simulation.
4. You can turn on an intervention.
i) REDUCE MOSQUITOS reduces the mosquito population.
ii) PROVIDE STERILIZED MEALS provides some -- but not all! -- of the villagers with sterile food.
iii) PROVIDE BOTTLED WATER provides some -- but not all! -- of the villagers with sterile water.
YOU WILL NEED TO SETUP AGAIN AFTER ENACTING AN INTERVENTION!
5. The HOSPITAL COUNTS plot shows the number of patients (symptomatic individuals who have wandered into the hospital). Once they recover, they leave the hospital.
There are many subtle differences between the hospital plots for the four possible vectors. One key difference is the peak number in the hospital, and it is this peak that is most affected by the 3 different interventions.
The simulation should be setup and run repeatedly, thus creating a data set of peaks that can be analyzed used a statistical inference on a hypothesis of a particular disease vector.