Evolutionary rescue of a parasite population by mutation rate evolution

Area of Science:

• Evolutionary biology
• Parasitology
• Public health

Background:

• Antibiotic resistance in parasites poses a significant public health threat.
• Understanding factors driving resistance evolution is crucial for evolutionary medicine.
• Mutation rate, a key factor, is often assumed fixed but can evolve.

Purpose of the Study:

• To investigate the impact of evolving mutation rates on parasite survival under drug treatment.
• To determine how epidemiological and genetic factors influence the role of mutation rate evolution in parasite adaptation.

Main Methods:

• Utilized an evolutionary rescue framework to model parasite population dynamics.
• Simulated scenarios with varying drug treatment regimes and parasite population genetic parameters.
• Analyzed the interplay between mutation rate evolution, virulence, and recombination.

Main Results:

• Evolving mutation rates significantly increase parasite survival probability in specific contexts, but not universally.
• The impact of mutation rate evolution on evolutionary rescue is highly dependent on epidemiological factors like virulence.
• Population genetic parameters, such as recombination rate, critically influence the adaptive potential conferred by mutation rate evolution.

Conclusions:

• Mutation rate evolution can be a double-edged sword, enhancing parasite adaptation in some scenarios but not others.
• Interventions targeting mutation rate evolution may be beneficial but require careful consideration of specific parasite-host-drug dynamics.
• The study highlights the complex interactions shaping the evolution of antibiotic resistance in parasitic diseases.