Highly Sensitive Virome Characterization of Aedes aegypti and Culex pipiens Complex from Central Europe and the Caribbean Reveals Potential for Interspecies Viral Transmission

Abstract

Mosquitoes are the most important vectors for arthropod-borne viral diseases. Mixed viral infections of mosquitoes allow genetic recombination or reassortment of diverse viruses, turning mosquitoes into potential virologic mixing bowls. In this study, we field-collected mosquitoes of different species (Aedes aegypti and Culex pipiens complex), from different geographic locations and environments (central Europe and the Caribbean) for highly sensitive next-generation sequencing-based virome characterization. We found a rich virus community associated with a great diversity of host species. Among those, we detected a large diversity of novel virus sequences that we could predominately assign to circular Rep-encoding single-stranded (CRESS) DNA viruses, including the full-length genome of a yet undescribed Gemykrogvirus species. Moreover, we report for the first time the detection of a potentially zoonotic CRESS-DNA virus (Cyclovirus VN) in mosquito vectors. This study expands the knowledge on virus diversity in medically important mosquito vectors, especially for CRESS-DNA viruses that have previously been shown to easily recombine and jump the species barrier.

Viral metagenomics reveals the presence of novel Zika virus variants in Aedes mosquitoes from Barbados

“…As a primary approach, viral metagenomic sequences were assigned by BLASTN search. Results and detailed characterization of the mosquito viral microbiome have been presented previously [ 18 ]. We did not identify any human pathogenic arboviruses among the total number of 33 viruses.…”

“…Biological significance of these metagenomic hits can be assessed only by evaluating goodness-of-assignment fit parameters. In a previous study we could show that mosquito-specific viruses and bat-associated viruses could be assigned with a high degree of confidence in this dataset [ 18 ]. Viruses of these groups are likely to establish stable infections in their mosquito hosts.…”

“…In a previous study, we could show that enrichment of intact virus particles revealed a rich and diverse viral metagenome in Ae. aegypti mosquitoes [ 18 ]. However, we did not detect any arbovirus sequences.…”

“…This is a common challenge in virus genome sequencing from complex DNA samples such as environmental metagenomes. As shown previously, field-collected mosquito samples are likely to contain large fractions of bacterial contaminants and highly abundant environmental virus populations [ 17 , 18 ]. Deep sequencing platforms have been used to enhance the sensitivity of metagenomics arbovirus detection, but increase sequencing costs [ 19 , 20 ].…”

Translational Research of Zoonotic Parasites: Toward Improved Tools for Diagnosis, Treatment and Control

“…Dahmana et al [3] showed how understanding the biology, distribution and vector competence of mosquitoes can assist disease surveillance and guide the development of novel strategies for the control of mosquito-borne diseases, particularly those involving insecticide-resistant vectors. Thannesberger et al [4] employed an NGS-based approach for virome characterisation in populations of medically important mosquitoes (Aedes aegypti and members of the Culex pipiens complex) and discovered a rich viral community in a diverse range of host species. Their study recorded novel virus sequences assigned, mainly, to circular Rep-encoding single-stranded (CRESS) DNA viruses.…”