The within-host population dynamics of normal flora in the presence of an invading pathogen and antibiotic treatments.
A mathematical competition model between normal flora and an invading pathogen was devised to allow analysis of bacterial infections in a host. The normal flora includes the various microorganisms that live on or within the host and act as a primary human immune system. Despite the important role of the normal flora, no mathematical study has been undertaken on models of the interaction between it and invading pathogens against a background of antibiotic treatment. To quantify key elements of bacterial behavior in a host, pairs of nonlinear differential equations were used to describe three categories of human health conditions, namely, healthy, latent infection, and active infection. In addition, a cutoff value was proposed to represent the minimum population level required for survival. The recovery of normal flora after antibiotic treatment was also included in the simulation because of its relation to human health recovery. The significance of each simulation parameter for the bacterial growth model was investigated. The devised simulation showed that bacterial proliferation rate, carrying capacity, initial population levels, and competition intensity have a significant effect on bacterial behavior. Consequently, a model was established to describe competition between normal flora and an infiltrating pathogen. Unlike other population models, the recovery process described by the devised model can describe the human health recovery mechanism.
Department of Chemical and Biological Engineering, Korea University, Seoul 136-713, Korea.
Jungmo
J
Kim
Dong Hwan
DH
Lee
Yoon Seok
YS
Song
Seong Woo
SW
Kang
Seung Wook
SW
Kim
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D054884:Host-Pathogen Interactions / Q000187:drug effects; D006801:Humans; D008954:Models, Biological; D017711:Nonlinear Dynamics; D011157:Population Dynamics
D000900:Anti-Bacterial Agents