  Multiple viruses are widely studied because of their negative effect on the
health of host as well as on whole population. The dynamics of coinfection is
important in this case.
  We formulated a SIR model that describes the coinfection of the two viral
strains in a single host population with an addition of limited growth of
susceptible in terms of carrying capacity. The model describes four classes of
a population: susceptible, infected by first virus, infected by second virus,
infected by both viruses and completely immune class. We proved that for any
set of parameter values there exist a globally stable equilibrium point. This
guarantees that the disease always persists in the population with a deeper
connection between the intensity of infection and carrying capacity of
population. Increase in resources in terms of carrying capacity promotes the
risk of infection which may lead to destabilization of the population.
