This is Map-Time Surfer.

Here we see the map of Vastopolis, with the position of some of the messages transmitted by its inhabitants depicted as dots in a 3D projection.

The interface is in Spanish but can be translated to English by pressing Control-L.

The messages shown belong to this period of time, which is a segment of 10 hours from the 504 hours that we have in the data.

To change the period shown, we simply click on the time line, or we can press the arrow keys for advance or rewind one hour at a time.

When we hover over the time line, a tooltip box shows us a detail of the number of cases found in each hour of data.

The color reference is as follows:
	Black refers to messages of people not yet infected,
	Red refers to the first message with symptoms of infection,
	Blue refers to following messages of people already infected,
	And yellow refers to messages about the truck accident of May the seventeenth.

Below this timeline there is another with a detailed zoom of the 10 hours being watched, with similar tooltip boxes and the same color reference.

When you see cases of interest…   being those first infections or truck accident related messages, you can select them with a rounded shape or a rectangular shape… and then select the time period here. You can verify that the right cases are selected… and then click here to save that selection. You can mark as many groups as you want… and then you can examine the messages selected along with the previous and following messages of the same person… here.

Here you have all the messages of a person, and marked the selected message of the previous screen.

Here you can see the path of this person, where he or she was before the marked message, and where he or she was after.

By clicking here you can see other persons… and then go back to the Message Map.

So, these clusters… which I will be selecting now. First we select a rectangular shape, and mark the area, and mark the time. Then a circular shape, and save. Another circular shape and the same time. Ok. Then I save. There. These clusters were investigated in detail, comparing their cases with those never infected. Their paths previous to the infection… seem random, although after that message there is a pattern, the person seems to go back home, back to work, back to home, and finally to an hospital or somewhere else.

Going back to the messages about the truck accident… they reveal that it caught fire and spilled its cargo, presumably on the river.

A few hours later we have the first infections in the city… and then the symptoms of gastrointestinal illness down the river.

Finally we see a lot of already infected people sending messages from the hospitals… but very few new infections.