  This paper studies a discrete-time time-varying multi-layer networked SIWS
(susceptible-infected-water-susceptible) model with multiple resources under
both single-virus and competing multi-virus settings. Besides the
human-to-human interaction, we also consider that the disease can diffuse on
different types of medium. We use \emph{resources} to refer to any media that
the pathogen of a virus can spread through, and do not restrict the resource
only to be water. In the single-virus case, we give a full analysis of the
system's behaviour related to its healthy state and endemic equilibrium. In the
multi-virus case, we show analytically that different equilibria appear driven
by the competition among all viruses. We also show that some analytical results
of the time-invariant system can be expanded into time-varying cases. Finally,
we illustrate the results through some simulations.
