Drivers of the likelihood of evolutionary rescue in response to novel infectious diseases.

Evolutionary rescue in response to novel infectious diseases is more likely with dynamical transmission and external reservoirs, especially when mortality-blocking alleles evolve.

• Why it matters: Understanding the factors that promote host adaptation to infectious diseases is crucial for predicting species survival and managing disease impacts, as ER can enable population recovery after declines.
• What they did: A stochastic mathematical model of host-pathogen dynamics was used to analyze how adaptive pathways and disease characteristics influence ER probability and timing, focusing on a novel allele conferring disease robustness.
• The result: ER is more probable with dynamical transmission than with lasting stressors, and is particularly associated with mortality-reducing alleles and transmission involving external reservoirs, facilitating population recovery.