  We study the propagation of an SIR (susceptible-infectious-recovered) disease
over an agent population which, at any instant, is fully divided into couples
of agents. Couples are occasionally allowed to exchange their members. This
process of couple recombination can compensate the instantaneous disconnection
of the interaction pattern and thus allow for the propagation of the infection.
We study the incidence of the disease as a function of its infectivity and of
the recombination rate of couples, thus characterizing the interplay between
the epidemic dynamics and the evolution of the population's interaction
pattern.
