Within-Host Dynamics of Antibiotic Resistance in Gonorrhea

Gonorrhea is a sexually transmitted bacterial infection caused by Neisseria gonorrhoeae that has become more resistant to a wide range of antibiotics in recent decades. We study the development of such resistance to antibiotics from the within-host perspective in an effort to capture the observed behavior of multiple bacterial strains. In order to examine how populations of susceptible and drug-resistant (high- and low-fitness) gonorrhea bacteria change over time, we propose a phenomenological system of three nonlinear ordinary differential equations that takes into account essential ideas such as the effects of differing treatment levels, initial bacterial population values, the mutation rates of bacteria due to multiple factors, and the response of the immune system. We then find the steady state solutions and use analytical and numerical techniques to determine their stability and analyze their biological significance.