  This paper formulates and studies the problem of controlling a networked SIS
model using a single input in which the network structure is described by a
connected undirected graph. A necessary and sufficient condition on the values
of curing and infection rates for the healthy state to be exponentially stable
is obtained via the analysis of signed Laplacians when the control input is the
curing budget of a single agent. In the case when the healthy state is
stabilizable, an explicit expression for the minimum curing budget is provided.
The utility of the algorithm is demonstrated using a simulation over a network
of cities in the northeastern United States.
