“Fighting antibiotic resistance using pulsed treatment regimes”

“Antibiotic resistance is a current and ever-increasing threat to global human health. Resistance evolves quickly because the leading treatment for bacterial infections is the administration of antibiotics at high concentrations; yet often, finding the correct, safe dosage for patients is not possible or takes too much time, allowing resistant strains to emerge. Resistant strains in antibiotic-free environments tend to have lower fitness than drug-sensitive strains and are out competed. It’s possible that we can take advantage of this phenomenon in treating microbial infections. CIDD researchers Christopher Baker, Matthew Ferrari, and Katriona Shea used mathematical models to test whether pulsed vaccination strategies can effectively exploit the competition between sensitive and resistant strains.

Baker, Ferrari, and Shea use stochastic models in which 1) the immune system responds to resistant and sensitive bacterial strains, 2) the immune system responds to bacterial strains can be resistant, partially resistant, or sensitive to antibiotics, or 3) limited resources drive competition between sensitive and resistant strains (no immune response). The wild type strain is able to mutate to become resistant in all models. Within these frameworks, different treatment schedules are employed, defined by: dose concentration (amount of drug administered each pulse), treatment frequency, pulse duration (fraction of time between pulses), and total treatment duration. Baker, Ferrari, and Shea tested how these aspects reduce pathogen burden and the probability of resistance emerging.”

Source: Dynamic Research in Epidemics