报告题目：Delayed action insecticides and their role in mosquito and malaria control

报告人：Rongsong Liu

报告时间：2023年12月13日（周三）09:00-11:00

报告地点：数学楼315会议室

报告摘要：There is considerable interest in the management of insecticide resistance in mosquitoes. One possible approach to slowing down the evolution of resistance is to use late-life-acting (LLA) insecticides that selectively kill only the old mosquitoes that transmit malaria, thereby reducing selection pressure favoring resistance. In this paper we consider an age-structured compartmental model for malaria with two mosquito strains that differ in resistance to insecticide, using an SEI approach to model malaria in the mosquitoes and thereby incorporating the parasite developmental times for the two strains. The human population is modeled using an SEI approach. We consider both conventional insecticides that target all adult mosquitoes, and LLA insecticides that target only old mosquitoes. According to linearized theory the potency of the insecticide affects mainly the speed of evolution of resistance. Mutations that confer resistance can also affect other parameters such as mean adult life span and parasite developmental time. For both conventional and LLA insecticides the stability of the malaria-free equilibrium, with only the resistant mosquito strain present, depends mainly on these other parameters. This suggests that the main long-term role of an insecticide could be to induce genetic changes that have a desirable effect on a vital parameter such as adult life span. However, when this equilibrium is unstable, numerical simulations suggest that a potent LLA insecticide can slow down the spread of malaria in humans but that the timing of its action is very important.

报告人简介：Rongsong Liu's research interests are mathematical biology, differential equations, dynamical systems, and their interface. Her research projects involve formulation, analysis, and applications of deterministic mathematical models for infectious diseases, and ecological systems. She gained her Ph.D. in 2006 from York University and Join in University of Wyoming since 2009 from Purdue University.