Otieno Fidel Gabriel, Barreaux Priscille, Belvinos Affognon Steeven, Makhulu Edward Edmond, Onchuru Thomas Ogao, Wairimu Anne Wambui, Omboye Stancy Mandere, King'ori Cynthia Nyambura, Sokame Bonoukpoè Mawuko, Nyamache Anthony Kebira, Herren Jeremy Keith
International Centre of Insect Physiology and Ecology, Nairobi, Kenya.
Department of Microbiology, Biochemistry and Biotechnology, Kenyatta University, Nairobi, Kenya.
Sci Rep. 2025 Aug 7;15(1):28839. doi: 10.1038/s41598-025-07414-7.
Microsporidia MB, a vertically transmitted endosymbiont of Anopheles mosquitoes, shows strong potential as a malaria control agent due to its ability to inhibit Plasmodium development within the mosquito host. To support its deployment in malaria transmission reduction strategies, it is critical to understand how environmental factors, particularly temperature, influence its infection dynamics. In this study, we investigated the impact of four temperature regimes (22 °C, 27 °C, 32 °C, and 37 °C) on Microsporidia MB prevalence and infection intensity by rearing mosquito larvae under controlled laboratory conditions. Our results demonstrate that elevated temperatures, especially 32 °C, significantly enhance both larval growth and Microsporidia MB infection rates. Population growth modeling further indicates that at 32 °C, an infected mosquito population can reach 1000 offspring within 15-35 days, representing a 4.7-, 1.3-, and 1.7-fold increase in dissemination potential compared to 22 °C, 27 °C, and 37 °C, respectively. Although mortality at 32 °C was approximately 20% higher than at 27 °C, this temperature emerged as the most favorable for mass-rearing Microsporidia MB-infected larvae. These findings provide the first insights into temperature-mediated dynamics of Microsporidia MB and support its potential for scalable implementation in malaria-endemic regions.
微孢子虫MB是按蚊的一种垂直传播的内共生体，由于其能够抑制疟原虫在蚊子宿主体内的发育，因此作为一种疟疾控制剂具有很强的潜力。为了支持其在减少疟疾传播策略中的应用，了解环境因素，特别是温度，如何影响其感染动态至关重要。在本研究中，我们通过在可控的实验室条件下饲养蚊虫幼虫，研究了四种温度条件（22℃、27℃、32℃和37℃）对微孢子虫MB流行率和感染强度的影响。我们的结果表明，温度升高，尤其是32℃，显著提高了幼虫的生长速度和微孢子虫MB的感染率。种群增长模型进一步表明，在32℃时，受感染的蚊虫种群可在15-35天内达到1000只后代，与22℃、27℃和37℃相比，传播潜力分别增加了4.7倍、1.3倍和1.7倍。虽然32℃时的死亡率比27℃时高出约20%，但该温度成为大规模饲养感染微孢子虫MB的幼虫最适宜的温度。这些发现首次揭示了温度介导的微孢子虫MB动态，并支持其在疟疾流行地区可扩展实施的潜力。
