  In this paper we present a versatile method for the investigation of
interaction networks and show how to use it to assess effects of indirect
interactions and feedback loops. The method allows to evaluate the impact of
optimization measures or failures on the system. Here, we will apply it to the
investigation of catastrophes, in particular to the temporal development of
disasters (catastrophe dynamics). The mathematical methods are related to the
master equation, which allows the application of well-known solution methods.
We will also indicate connections of disaster management with excitable media
and supply networks. This facilitates to study the effects of measures taken by
the emergency management or the local operation units. With a fictious, but
more or less realistic example of a spreading epidemic disease or a wave of
influenza, we illustrate how this method can, in principle, provide decision
support to the emergency management during such a disaster. Similar
considerations may help to assess measures to fight the SARS epidemics,
although immunization is presently not possible.
