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Ciota, A.

Publications and source records attributed to Ciota, A..

5 recordsLinked to original sources
bioRxiv2025

The impact of climate change on transmission season length: West Nile virus as a case study

BackgroundClimate change is accelerating the spread of temperature-sensitive vector-borne diseases such as West Nile virus (WNV), the most widespread mosquito-borne disease in the United States, with 2,400 reported cases in 2024. In New York State (NYS), where WNV first emerged in the U.S., mean temperatures have increased by 1.4{degrees}C since the early 1900s. Although temperature is a well-established driver of WNV transmission, its effect on transmission season length remains poorly quantified. This study examines whether WNV transmission seasons have lengthened in NYS and whether these changes are associated with increased disease risk, shifts in seasonal timing, and anthropogenic climate change. MethodsWe integrated daily county-level observational data from 1999-2024, including temperature, mosquito surveillance, and human case data, with climate model simulations spanning 1850-2024 to assess trends in transmission season length. FindingsBased on observed temperature suitability, the WNV transmission season in NYS has lengthened by an average of 20 days over the past 25 years, beginning 3.8 days earlier and ending 16.3 days later. Longer transmission seasons are positively associated with higher WNV prevalence in both mosquito vectors and humans. While such changes could occur in the absence of global warming, climate model analyses indicate that the observed increase in season length is 6.4 times more likely under historical climate forcing since 1900 than under pre-industrial conditions. InterpretationThese findings demonstrate that climate change is reshaping the phenology and burden of WNV transmission. FundingSupported by NIH, NSF, Stanford University, and the Fogarty International Center. Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSWe searched Google Scholar for publications from 1999 to 2024 using the term "West Nile virus and season length," yielding 18,200 results. Previous studies focused on how climatic factors affect transmission and its seasonality in the United States, but none assessed how climate change influences transmission season duration. We analyzed over two decades of data to link extended WNV transmission seasons with increased vector and human prevalence. Additionally, we evaluated the causal role of climate warming using simulated climate data and counterfactual analyses. Added value of this studyUsing daily temperature and WNV case data from 1999- 2024, we found that the WNV transmission season in NYS has lengthened by an average of 20 days. The season now begins 3.8 days earlier and ends 16.3 days later. Longer seasons were associated with higher prevalence in mosquitoes and humans. Climate model simulations indicate that human-driven greenhouse gas emissions have significantly extended the WNV season, making observed trends in season length, onset, and conclusion 6, 2, and 16 times more likely, with implications for mosquito infection and human disease risk. Implications of all available evidenceOur findings suggest that climate change is lengthening WNV transmission seasons, a phenomenon likely relevant to other temperature-sensitive vector-borne diseases. As warming continues, extended transmission seasons may amplify risks for WNV and other vector-borne diseases, underscoring the need for climate-adaptive public health surveillance and intervention strategies.

ecology↗
bioRxiv2023

Multi-Omics Analysis Of Antiviral Interactions Of Elizabethkingia anophelis And Zika Virus

BackgroundThe microbial communities residing in the mosquito midgut play a key role in determining the outcome of mosquito pathogen infection. Elizabethkingia anophelis, originally isolated from the midgut of Anopheles gambiae, has drawn much attention due to its close association with Aedes and Anopheles mosquitoes, primary vectors of dengue virus and malaria parasites, respectively. E. anophelis possesses a broad-spectrum antiviral phenotype, yet a gap in knowledge regarding the mechanistic basis of its interaction with viruses exists. Methodology/Principal findingsTo further understand the antiviral interactions between E. anophelis and Zika virus (ZIKV), we utilized a non-targeted multi-omics approach, analyzing lipids, proteins, and metabolites of cell monolayers co-infected with ZIKV and E. anophelis. We further assessed the gene expression of ZIKV when cultured in the presence of E. anophelis. ZIKV cultured in the presence of E. anophelis resulted in an attenuated replicative fitness and unproductive virus infection. Further, in this treatment, we observed lower levels of the nonstructural protein 5 (NS5) and RNA-directed RNA polymerase (RdRp) protein. Lastly, a significant decrease in arginine levels, an essential requirement for viral replication and progression of viral infection was observed. Conclusions/SignificanceThis study provides insights into the molecular basis of E. anophelis antiviral phenotype. These findings improve our knowledge of how microbes and viruses interact to impact viral replication. In the future, our findings can be utilized to unravel the mechanism behind the antiviral phenotype of E. anophelis, and this can help develop novel paradigms for viral therapeutics. AUTHOR SUMMARYZika is a re-emerging disease and is endemic in many regions of sub-Saharan Africa, Asia and Latin America. It remains a major public health threat and lacks FDA-approved therapeutics or vaccines, hence the urgent need for the identification of alternative approaches that limit the transmission of the pathogens by its primary vector, Aedes spp. The microbial communities residing in the mosquito midgut play a key role in determining the outcome of mosquito pathogen infection. Flavobacteria dominates the mosquito midgut including Elizabethkingia, which is a gram-negative bacillus prevalent in Aedes and Anopheles species of mosquitoes. E. anophelis, a poorly studied midgut microbe, has a broad-spectrum antiviral phenotype, yet the mechanism of its antiviral action is unknown. In this study, we have identified several pathways as well as Zika virus proteins perturbed when the Zika virus is cultivated in the presence of E. anophelis. Our findings do not only provide insights into microbial, virus interaction but could be harnessed to develop novel antiviral tools.

microbiology↗
bioRxiv2019

Increased temperatures reduce the vectorial capacity of Aedes mosquitoes for Zika virus

Rapid and significant range expansion of both ZIKV and its Aedes host species has resulted in ZIKV being declared a global health threat. Mean temperatures are projected to increase globally, likely resulting in alterations of the transmission potential of mosquito-borne pathogens. The relationship between temperature and ZIKV transmission has not been well characterised for Aedes aegypti and Aedes albopictus.\n\nTo understand the effect of diurnal temperature range on the vectorial capacity of Aedes aegypti and Aedes albopictus for ZIKV, factors contributing to transmission potential were measured at different temperature regimens. Their longevity and blood feeding rates were assessed, and vector competence was determined following feeding on blood meals with 8.3 log10 PFU/ml ZIKV.\n\nHigher temperature resulted in decreased longevity of Ae. aegypti [Log-rank (Mantel-Cox) Test, Chi-square, df 35.66, 5 P (<0.0001)] and a significant decrease in blood feeding rates across groups [Z score (-5.8478) P (0.0444)]. Temperature had a population and species-specific impact on ZIKV infection rates. Overall, Ae. albopictus reared at the lowest temperature regimen demonstrated the highest vectorial capacity (1.63) and the highest transmission efficiency (57%). Temperature increases decreased vectorial capacity across groups, yet the largest decreases were measured for Ae. aegypti.\n\nThe results of this study suggest that future climate change could significantly impact vector competence, blood feeding behavior and longevity, and therefore decrease the overall vectorial capacity of Aedes mosquitoes. It is also clear that this impact is likely to be both species and population-specific.

microbiology↗
bioRxiv2019

Zika virus infection and temperature significantly impact Aedes albopictus gut microbiota

Elizabethkingia anophelis has been the cause of four outbreaks with significant morbidity and mortality. Its transmission routes remain unknown and no point source of infection has been identified. Here we show that E. anophelis can be found in the saliva of Aedes mosquitoes, suggesting the novel possibility of vector-borne transmission of this bacterium. We additionally characterized diverse microbial communities in Aedes midguts, salivary glands and saliva. To the best of our knowledge, this represents the first description of the microbiome of Aedes saliva. Further, we demonstrate that increased abundance of E. anophelis is associated with decreased susceptibility and replication of Zika virus (ZIKV) in the midgut of Aedes mosquitoes, suggesting a novel transmission barrier for arboviruses transmitted by Aedes mosquitoes. Together, these results demonstrate the complex relationships between the mosquito, the midgut microbial community and arboviruses and offer insights into the epidemiology and control of emerging bacterial and viral pathogens. Author SummaryElizabethkingia anophelis has in the recent past caused outbreaks different parts of the world resulting both in morbidity and mortality. Until now, to the best of our knowledge, no study has been able to demonstrate that this bacterium can be transmitted by mosquitoes. We have demonstrated for the first time that Elizabethkingia anophelis is present in the saliva of both infected and non-infected Aedes mosquitoes. Further, we have shown that it confers an inhibitory effect on Zika virus establishment in the midguts of Aedes mosquitoes. Together, these results potentially display the potential for vector borne transmission of E. anophelis as well as a novel transmission barrier of ZIKV. Lastly, we have for the first time characterized salivary microbes of Aedes mosquitoes necessitating the investigation of the impact of salivary microbes in severity of disease in vertebrate hosts.

microbiology↗