1.1 Data Visualisation
Data requirements: Case data, Potential
outbreak source locations
Description: The most basic use of a Geographic Information System (GIS) is to visualise data spatially.
Having collated as comprehensive a record as possible of the locations cases have visited, the
routes they have travelled and the dates they have occupied those spaces, it is possible to
visualise the data in a number of ways. A GIS enables us to visualise such a dataset at either the
individual case level or as a composite of all patients (or perhaps a subset). Attribution
attached to the 'point' and 'line' geometries, such as a date, also enables us to view the data
in time-series, perhaps visualising daily movements of cases to identify common spaces they
have either visited or moved through. Essentially by collecting data of this nature, which can
be easily entered into a GIS, those investigating an outbreak are presented with a very simple,
very flexible and potentially very informative spatial picture of how all cases have interacted
with their environment.
GIS tools required: All GIS systems will be capable of displaying spatial data. The
ability to present data in a time-series animation may also be useful.
Considerations for a cross-border outbreak: In a cross border outbreak it is unlikely
that individual-based case data will be shared between nations. As such
it would not be possible to present a complete picture of the locations visited and routes
taken by each case as described above. Individual-based case data would be replaced by data
aggregated to small-area geographic units as described in section 2.1 Case
data, making thematic mapping possible for information such as: the number of home
locations per area; the number of locations visited in the area; the number of travel routes
that have passed through the area; and the number of unique cases that have been through an
area.