Competitive exclusion in gonorrhea models and other sexually transmitted diseases

A heterosexually active population is exposed to two competing strains or two distinct sexually transmitted pathogens. It is assumed that a host cannot be invaded simultaneously by both disease agents and that when symptoms appear, a function of the pathogen or strain virulence, individuals recover. We conclude that in a behaviorally and genetically homogeneous population coexistence is not possible except under very special circumstances. The mathematical qualitative analysis of our model is complete; that is, we provide the global stability analysis of the stationary states. We conclude this manuscript with two extensions. The first allows for the possibility that a host may face multiple competing strains, while the second looks at the effects on coexistence of the host's age of infection when two strains compete for the same host.