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Supporting data for <b>Drivers, Composition and Potential for Innovative Vector Control Approaches in the mosquito</b>

<p dir="ltr">This is the Data repository for the thesis entitled <b>Drivers, Composition and Potential for Innovative Vector Control Approaches in the mosquito</b>. </p><p dir="ltr">Brief project description</p><p dir="ltr">Mosquito-borne diseases kill more humans than humans do and have done so for a long time. The most significant diseases transmitted by mosquitoes currently lack effective vaccines, and existing control methods face increasing resistance. In a holistic health context, new approaches have emerged to control mosquitoes. Notably, growing interest in the mosquito microbiome as a tool for vector control is emerging, driven by the use of the Wolbachia bacterium, a natural bacterial symbiont that can reduce virus transmission in its non-native host species.</p><p dir="ltr">This thesis examined the mosquito microbiome to identify potential new targets for vector control. The initial part of this work is a meta-analysis of mosquito microbiome studies, covering 5701 samples and 60 different studies. We previously highlighted bacteria that were overlooked due to their low abundance in individual studies but are more prevalent globally, such as Methylobacterium, Acinetobacter, or Sphingomonas. Diversity analyses revealed the highly complex nature of the microbiota, although the main factors remain the climate where mosquitoes develop and their genus.</p><p dir="ltr">These larger phenomena were analysed in greater detail through an examination of the Hong Kong mosquito microbiome. A set of 196 samples subjected to 16S rRNA gene sequencing, covering three mosquito species across 16 locations in Hong Kong over a one-year period, showed higher diversity in the summer. Additionally, the analysis of 17 environmental variables indicated that diurnal range had the greatest influence on diversity. The analysis of bacterial composition revealed an overwhelming abundance of Wolbachia in all three mosquito species, increasing with temperature and rainfall.</p><p dir="ltr">Considering Wolbachia's known antiviral properties, it raises the question of whether the absence of sustained Dengue virus circulation in Hong Kong is due to the presence of this bacterium. The ability of Hong Kong mosquitoes to transmit Dengue virus was therefore experimentally tested, using mosquitoes harbouring different strains of the symbiont. The results indicated that mosquitoes with both strains of Wolbachia were more capable of transmitting Dengue than those without Wolbachia or with only one strain.</p><p dir="ltr">The final part of this thesis addresses the need for a more refined method of pre-screening targets. Current approaches are limited to testing several bacteria in the hope that one will be effective. By analysing transcriptomics samples from previously published <i>Aedes albopictus</i> sequencing, we correlated the presence or absence of microbial taxa with the expression of a panel of immune genes. While most Bacteria and Viruses studied showed correlations with decreased immune gene expression, some, such as Doliuvirus or Siphonobacter, were associated with increased immune gene expression. These promising results highlight the trend towards refining current, labour-intensive techniques to develop more efficient methods.</p><p dir="ltr">Overall, this thesis enabled the description and deciphering of important drivers of the microbiome, as well as highlighting promising novel targets through both conventional state-of-the-art techniques and innovative methods.</p><p dir="ltr">The description of the files is in the attached file named Readme.txt<br></p>

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