Uncovering the Worldwide Diversity and Evolution of the Virome of the Mosquitoes Aedes aegypti and Aedes albopictus

Abstract

Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the Asian tiger mosquito, are the most significant vectors of dengue, Zika, and Chikungunya viruses globally. Studies examining host factors that control arbovirus transmission demonstrate that insect-specific viruses (ISVs) can modulate mosquitoes’ susceptibility to arbovirus infection in both in vivo and in vitro co-infection models. While research is ongoing to implicate individual ISVs as proviral or antiviral factors, we have a limited understanding of the composition and diversity of the Aedes virome. To address this gap, we used a meta-analysis approach to uncover virome diversity by analysing ~3000 available RNA sequencing libraries representing a worldwide geographic range for both mosquitoes. We identified ten novel viruses and previously characterised viruses, including mononegaviruses, orthomyxoviruses, negeviruses, and a novel bi-segmented negev-like group. Phylogenetic analysis suggests close relatedness to mosquito viruses implying likely insect host range except for one arbovirus, the multi-segmented Jingmen tick virus (Flaviviridae) in an Italian colony of Ae. albopictus. Individual mosquito transcriptomes revealed remarkable inter-host variation of ISVs within individuals from the same colony and heterogeneity between different laboratory strains. Additionally, we identified striking virus diversity in Wolbachia infected Aedes cell lines. This study expands our understanding of the virome of these important vectors. It provides a resource for further assessing the ecology, evolution, and interaction of ISVs with their mosquito hosts and the arboviruses they transmit.

Transcriptomics Reveal Several Novel Viruses from Canegrubs (Coleoptera: Scarabaeidae) in Central Queensland, Australia

“…There are some other members of the Reoviridae that infect insects, and they are mainly classified under the genera Orbivirus and Cypovirus . Orbiviruses, such as the Umatilla virus [ 57 ], Aedes orbi-like virus [ 58 ], Anopheles hinesorum orbivirus [ 59 ], and bluetongue virus [ 60 ], are previously reported from different species of mosquitoes and midges across the world, including Australia. Cypovirus is another genus in this family that infects insects, such as the Heliothis armigera cypovirus [ 61 ] and Bombyx mori cypovirus [ 62 ], which are transmitted by contact or faecal–oral routes and, in some cases, cause significant mortality in insect populations [ 55 ].…”

Reporter Flaviviruses as Tools to Demonstrate Homologous and Heterologous Superinfection Exclusion

“…There has been a recent push toward discovering and characterising ISVs in vector mosquitoes [ 55 , 56 , 57 ]. However, the interactions between ISV/ISFs and pathogenic arboviruses in the mosquitoes remain poorly defined.…”

Recombinant Mosquito Densovirus with Bti Toxins Significantly Improves Pathogenicity against Aedes albopictus

“…Densoviruses (DNVs) are single-stranded, paraspherical DNA viruses (18-22 nm) that are non-enveloped and belong to the family Parvoviridae [7]. Mosquito densoviruses (MDVs) have been detected in many vector mosquito species, including Aedes aegypti, Aedes albopictus, Anopheles gambiae, Anopheles sinensis, Culex pipiens, and Culex pipiens pallens [9][10][11][12][13], that can replicate in numerous tissues, such as the midgut, anal papillae, Malpighian tubules, nerves, muscle fibers, fat body, and salivary glands, causing systemic infection [6,14]. Infected larvae have deformed segments and a cuticle of a semitransparent or whitish color with dense hypertrophied nuclei [15][16][17].…”