Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, AB, T6G 2G1, Canada.
Department of Applied Mathematics, University of Western Ontario, London, ON, N6A 5B7, Canada.
Bull Math Biol. 2019 Jul;81(7):2569-2595. doi: 10.1007/s11538-019-00619-8. Epub 2019 Jun 3.
Recent experimental study suggests that the engineered symbiotic bacteria Serratia AS1 may provide a novel, effective and sustainable biocontrol of malaria. These recombinant bacteria have been shown to be able to rapidly disseminate throughout mosquito populations and to efficiently inhibit development of malaria parasites in mosquitoes in controlled laboratory experiments. In this paper, we develop a climate-based malaria model which involves both vertical and horizontal transmissions of the engineered Serratia AS1 bacteria in mosquito population. We show that the dynamics of the model system is totally determined by the vector reproduction ratio [Formula: see text], and the basic reproduction ratio [Formula: see text]. If [Formula: see text], then the mosquito-free state is globally attractive. If [Formula: see text] and [Formula: see text], then the disease-free periodic solution is globally attractive. If [Formula: see text] and [Formula: see text], then the positive periodic solution is globally attractive. Numerically, we verify the obtained analytic result and evaluate the effects of releasing the engineered Serratia AS1 bacteria in field by conducting a case study for Douala, Cameroon. We find that ideally, by using Serratia AS1 alone, it takes at least 25 years to eliminate malaria from Douala. This implies that continued long-term investment is needed in the fight against malaria and confirms the necessity of integrating multiple control measures.
最近的实验研究表明，工程共生菌serratia AS1 可能为疟疾的防治提供一种新颖、有效和可持续的方法。这些重组细菌已被证明能够在蚊子种群中迅速传播，并在受控的实验室实验中有效地抑制疟原虫在蚊子中的发育。在本文中，我们开发了一个基于气候的疟疾模型，该模型涉及蚊子种群中工程serratia AS1 细菌的垂直和水平传播。我们表明，模型系统的动力学完全由向量繁殖率 [Formula: see text] 和基本繁殖率 [Formula: see text] 决定。如果 [Formula: see text]，则无蚊子状态是全局吸引的。如果 [Formula: see text] 且 [Formula: see text]，则无病周期解是全局吸引的。如果 [Formula: see text] 且 [Formula: see text]，则正周期解是全局吸引的。数值上，我们验证了所得到的解析结果，并通过对喀麦隆杜阿拉的案例研究来评估在野外释放工程化serratia AS1 细菌的效果。我们发现，理想情况下，仅使用serratia AS1 就需要至少 25 年才能从杜阿拉消除疟疾。这意味着需要对疟疾防治工作进行持续的长期投资，并证实了整合多种控制措施的必要性。
