Symbiotic bacteria have a significant impact on the formation of defensive mechanisms against fungal pathogens and insecticides. The microbiome of the mosquito Aedes aegypti has been well studied; however, there are no data on the influence of insecticides and pathogenic fungi on its structure. The fungus Metarhizium robertsii and a neurotoxic insecticide (avermectin complex) interact synergistically, and the colonization of larvae with hyphal bodies is observed after fungal and combined (conidia + avermectins) treatments. The changes in the bacterial communities (16S rRNA) of Ae. aegypti larvae under the influence of fungal infection, avermectin toxicosis, and their combination were studied. In addition, we studied the interactions between the fungus and the predominant cultivable bacteria in vitro and in vivo after the coinfection of the larvae. Avermectins increased the total bacterial load and diversity. The fungus decreased the diversity and insignificantly increased the bacterial load. Importantly, avermectins reduced the relative abundance of Microbacterium (Actinobacteria), which exhibited a strong antagonistic effect towards the fungus in in vitro and in vivo assays. The avermectin treatment led to an increased abundance of Chryseobacterium (Flavobacteria), which exerted a neutral effect on mycosis development. In addition, avermectin treatment led to an elevation of some subdominant bacteria (Pseudomonas) that interacted synergistically with the fungus. We suggest that avermectins change the bacterial community to favor the development of fungal infection.

共生细菌对防御真菌病原体和杀虫剂的防御机制的形成具有重要影响。埃及伊蚊（Aedes aegypti）的微生物组已得到很好的研究。但是，没有关于杀虫剂和致病真菌对其结构的影响的数据。真菌罗氏沼虾和一种神经毒性杀虫剂（阿维菌素复合物）协同相互作用，经过真菌和联合（分生孢子+阿维菌素）处理后，观察到幼虫的菌丝体定殖。Ae细菌群落（16S rRNA）的变化。埃及研究了在真菌感染，阿维菌素中毒及其组合影响下的幼虫。此外，我们研究了幼虫共感染后真菌与主要可培养细菌之间的相互作用。阿维菌素增加了细菌总数和多样性。真菌降低了多样性，并没有明显增加细菌载量。重要的是，阿维菌素降低了微细菌（放线菌）的相对丰度，在体外和体内试验中，这种细菌对真菌表现出强烈的拮抗作用。阿维菌素治疗导致金黄色葡萄球菌丰度增加（黄杆菌），对真菌病的发展具有中性作用。此外，阿维菌素治疗导致与细菌协同相互作用的一些主要细菌（假单胞菌）升高。我们建议阿维菌素改变细菌群落，以促进真菌感染的发展。