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Climate change is significantly impacting the geographic range of many animal species and their associated microorganisms, hence influencing emergence of vector-borne diseases. Mosquito-borne viruses represent a potential major reservoir of human pathogens, highlighting the need for improved understanding of ecological factors associated with variation in the mosquito viral community (virome). Here, a subtractive hybridization method coupled with RNAseq of individual mosquito specimens was used to profile RNA viromes of individual co-occurringAedes albopictusandAedes vexansmosquitoes across a 2,000 km spatial scale. Samples were collected and archived by the National Ecological Observatory Network (NEON) from four ecologically variable sites in the Southeastern United States between 2018 and 2019. Results of multivariate analysis suggest that mosquito species are an important factor in RNA viral community composition. Significantly higher viral diversity was detected inA. albopictuscompared toA.vexans. However, season, year, and site of sample collection did not show strong association with virome profiles, supporting the hypothesis that factors unique to the mosquito host species (e.g., larval habitat or vector competence) influence the structure of mosquito viromes.
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Modeling the effects of Aedes aegypti’s larval environment on adult body mass at emergence
Mosquitoes vector harmful pathogens that infect millions of people every year, and developing approaches to effectively control mosquitoes is a topic of great interest. However, the success of many control measures is highly dependent upon ecological, physiological, and life history traits of mosquito species. The behavior of mosquitoes and their potential to vector pathogens can also be impacted by these traits. One trait of interest is mosquito body mass, which depends upon many factors associated with the environment in which juvenile mosquitoes develop. Our experiments examined the impact of larval density on the body mass of Aedes aegypti mosquitoes, which are important vectors of dengue, Zika, yellow fever, and other pathogens. To investigate the interactions between the larval environment and mosquito body mass, we built a discrete time mathematical model that incorporates body mass, larval density, and food availability and fit the model to our experimental data. We considered three categories of model complexity informed by data, and selected the best model within each category using Akaike’s Information Criterion. We found that the larval environment is an important determinant of the body mass of mosquitoes upon emergence. Furthermore, we found that larval density has greater impact on body mass of adults at emergence than on development time, and that inclusion of density dependence in the survival of female aquatic stages in models is important. We discuss the implications of our results for the control of Aedes mosquitoes and on their potential to spread disease.
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- Award ID(s):
- 1853495
- PAR ID:
- 10331201
- Editor(s):
- Perkins, Alex
- Date Published:
- Journal Name:
- PLOS Computational Biology
- Volume:
- 17
- Issue:
- 11
- ISSN:
- 1553-7358
- Page Range / eLocation ID:
- e1009102
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1371/journal.pcbi.1009102
