A gonorrhea model treating sensitive and resistant strains in a multigroup population.

In recent years gonorrhea infection with antibiotic-resistant strains, especially PPNG, has become a significant public health problem. Drawing on the gonorrhea model of Lajmanovich and Yorke, a multigroup model that embraces both resistant and sensitive strains of the organism is introduced. It is shown that, like the Lajmanovich and Yorke (single-strain) model, in the general case the sensitive-resistant model has a unique globally asymptotic equilibrium. As a function of the interplay between contact rates, cure rates, and reversion rates, the equilibrium can lead to endemic infection with sensitive infection only, resistant infection only, or both, or to elimination of sensitive and resistant infection.