Vector Ecology Research Articles

Vectorial dynamics underpinning current and future tick-borne virus emergence in Europe

Tick-borne diseases pose a growing threat to human and animal health in Europe, with tick-borne encephalitis virus (TBEV) and Crimean-Congo haemorrhagic fever virus (CCHFV), vectored by Ixodes ricinus and Hyalomma marginatum, respectively, emerging as primary public health concerns. The ability of ticks to transmit pathogens to multiple hosts and maintain infections across life stages makes them highly efficient vectors. However, many aspects of tick ecology and vectorial capacity remain understudied. This review examines key factors contributing to the vectorial competence of European ticks and their associated viruses. We first explore the influence of climate change on vector and disease ecology, using TBEV and CCHFV as case studies. We then analyse the role of the tick antiviral response in shaping vector competence. By integrating these elements, this review aims to enhance our understanding of tick-borne viral diseases and support the development of public health strategies, particularly through the One Health framework, to mitigate their impact in Europe.

Reemergence of Oropouche Virus in the Americas and Risk for Spread in the United States and Its Territories, 2024.

Oropouche virus has recently caused outbreaks in South America and the Caribbean, expanding into areas to which the virus was previously not endemic. This geographic range expansion, in conjunction with the identification of vertical transmission and reports of deaths, has raised concerns about the broader threat this virus represents to the Americas. We review information on Oropouche virus, factors influencing its spread, transmission risk in the United States, and current status of public health response tools. On the basis of available data, the risk for sustained local transmission in the continental United States is considered low because of differences in vector ecology and in human-vector interactions when compared with Oropouche virus-endemic areas. However, more information is needed about the drivers for the current outbreak to clarify the risk for further expansion of this virus. Timely detection and control of this emerging pathogen should be prioritized to mitigate disease burden and stop its spread.

Global health at local level: characterization of tropical diseases in northern Portugal, 2020-2024

Abstract Background The escalating global prevalence and geographic spread of tropical diseases pose significant global health risks worldwide, with local implications. In Portugal, these diseases require mandatory notification. Concerns were raised following the detection of Aedes albopictus mosquitoes in mainland Portugal in 2017, alongside a Dengue outbreak in Madeira in 2012. Despite Portugal being declared malaria-free, the detection of Anopheles mosquitoes also raises concerns. This study aims at characterizing notified cases of tropical diseases in two cities in Northern Portugal since 2020. Methods A retrospective study of Malaria, Dengue, Zika, and Chikungunya cases in the Maia & Valongo’s Public Health Unit included data from the National Epidemiological Surveillance System covering January 2020 to April 2024. Descriptive analysis was conducted using SPSS IBM for iOS® v29. Results are presented as mean ± standard deviation for continuous variables and proportions for categorical ones. Results Five malaria cases were reported, predominantly affecting males (80%), with an average age of 34±16.96 years. Four were Portuguese and one Angolan. All cases were imported, mostly from Angola (80%). Etiological analysis revealed two cases of Plasmodium malariae and three of Plasmodium falciparum. All were hospitalized, no deaths. Four dengue cases were documented, 50% in males, averaged 33±24.73 years. Three were Portuguese and one Mozambican. One was hospitalized with no deaths. All cases were imported from Brazil, Cuba, Indonesia, and islands of Saint Martin/Saint-Barthélemy. No Zika or Chikungunya confirmed cases were identified during this period. Conclusions The increasing incidence of Dengue and Malaria underscores the critical connection between infectious diseases, vector ecology, and global health security. This study highlights the risk of imported Dengue and Malaria cases, emphasizing the imperative for surveillance and preventive actions to protect public health. Key messages • Dengue and Malaria cases in Portugal underline the importance of international collaboration and robust strategies. • Stepped-up surveillance is key to protecting vulnerable groups from imported infections.

Revisiting the epidemiological role of a native vector in Northern California vineyards

Abstract Effective disease management hinges on an accurate understanding of the ecological and epidemiological underpinnings of the pathosystem. New epidemics may prompt consideration of whether knowledge gaps or changes to the pathosystem warrant revision of management strategies. Pierce’s disease of grapevines is highly episodic in coastal Northern California vineyards, with modest incidence in most years punctuated by occasionally severe epidemics. To better understand what was driving a developing epidemic in the region, we revaluated what is known about the ecology and epidemiological role of the dominant vector, the blue-green sharpshooter Graphocephala atropunctata. We monitored vector spatiotemporal dynamics at 32 vineyards over three years, surveyed plant community composition in the adjacent habitat to understand its link to vector recruitment, and quantified patterns of natural infectivity for the pathogen Xylella fastidiosa. Overall, the results were consistent with past studies of G. atropunctata ecology. For example, the scale of dispersal from source habitat and seasonal patterns in activity were generally similar to those documented in prior studies. The results also confirmed the influence of adjacent plant community composition on G. atropunctata activity in vineyards, and the role of riparian habitat and select plant taxa as vector sources. Nonetheless, further consideration of the epidemiological significance of certain features of the pathosystem may be warranted, especially those related to seasonality in X. fastidiosa infection in vectors. A marked increase in infected G. atropunctata late in the season likely reflects pathogen acquisition from infected grapevines, which may have implications for disease management strategies.

Understanding Viral Haemorrhagic Fevers: Virus Diversity, Vector Ecology, and Public Health Strategies.

Viral haemorrhagic fevers encompass a diverse group of severe, often life-threatening illnesses caused by viruses from multiple families, including Arenaviridae, Filoviridae, Flaviviridae, Hantaviridae, Nairoviridae, Peribunyaviridae, and Phenuiviridae. Characterised by fever and haemorrhagic symptoms, these diseases challenge public health systems by overwhelming healthcare facilities, complicating diagnostic processes, and requiring extensive resources for containment and treatment, especially in resource-limited settings. This discussion explores the intricate relationships between VHFs and their transmission vectors-both animal and arthropod-and examines the impact of ecological and geographic factors on disease spread. The primary transmission of VHFs typically occurs through direct contact with infected animals or via bites from haematophagous arthropods, facilitating zoonotic and, at times, human-to-human transmission. With an emphasis on the role of diverse wildlife, domesticated animals, and vectors such as mosquitoes and ticks in the epidemiology of VHFs, there is a recognised need for robust surveillance and strategic public health responses to manage outbreaks. This review discusses the necessity of interdisciplinary approaches that integrate virology, ecology, and public health to enhance diagnostic capabilities, develop vaccines and antivirals, and improve outbreak interventions. Exploring the ecological and biological dynamics of VHFs will help bolster a deeper understanding of these emerging viruses and underpin preparation for future outbreaks. The importance of enhanced global cooperation, continuous research, and collaboration to mitigate the public health threats posed by these complex infections is a central theme, serving as a foundational strategy to reinforce worldwide preparedness and response efforts. Future directions include addressing gaps in vaccine development and tailoring public health strategies to the unique challenges of managing VHFs, such as the rapid mutation rates of viruses, the need for cold chain logistics for vaccine distribution, and socio-economic barriers to healthcare access, in order to ensure readiness for and effective response to emerging threats worldwide.

The potential of gene drives in malaria vector species to control malaria in African environments

Gene drives are a promising means of malaria control with the potential to cause sustained reductions in transmission. In real environments, however, their impacts will depend on local ecological and epidemiological factors. We develop a data-driven model to investigate the impacts of gene drives that causes vector population suppression. We simulate gene drive releases in sixteen ~ 12,000 km2 areas of west Africa that span variation in vector ecology and malaria prevalence, and estimate reductions in vector abundance, malaria prevalence and clinical cases. Average reductions in vector abundance ranged from 71.6–98.4% across areas, while impacts on malaria depended strongly on which vector species were targeted. When other new interventions including RTS,S vaccination and pyrethroid-PBO bednets were in place, at least 60% more clinical cases were averted when gene drives were added, demonstrating the benefits of integrated interventions. Our results show that different strategies for gene drive implementation may be required across different African settings.

A Five-Year Malaria Prevalence/Frequency in Makenene in a Forest-Savannah Transition Ecozone of Central Cameroon: The Results of a Retrospective Study.

Understanding the epidemiological features of malaria is a key step to monitoring and quantifying the impact of the current control efforts to inform future ones. This study establishes the prevalence and frequency of malaria in a forest-savannah ecozone for 5 consecutive years in Cameroon. A retrospective study was conducted in 3 health centers of Makenene from 2016 to 2020, a period covering the second long-lasting insecticide net mass distribution campaign. Malaria infectious records were reviewed from laboratory registers. The difference in exposure to malaria was estimated using a regression logistic model. A total of 13525 patients underwent malaria diagnostic tests, with a general malaria prevalence of 65.3%. A greater prevalence of malaria was observed in males (68.39%) compared to females (63.14%). The frequency of consultations in health centers was dominated by females, with a gender ratio (M/F) of 0.66. Annual trends in malaria prevalence slightly varied from 2016 to 2020, exceeding 60%: 65.2% in 2016; 66.7% in 2017, 68.1% in 2018, 63.2% in 2019, and 65.3% in 2020, with a significant seasonal variation (p < 0.0001). The highest malaria prevalence was observed during the short rainy season, no matter the year. Among positive cases, the most represented age groups were 6-15 (p < 0.0001), followed by those under 5, while the age group >25 years was the least represented. Close monitoring and additional intervention measures for malaria control are needed, as are more studies on vector bionomics and transmission patterns.

2024 AMCA MEMORIAL LECTURE HONOREE: MIR SUBHAN MULLA 1925-20231.

From 1979 to 2024, 51 individuals have been recognized as AMCA honorees for their lifetime achievements in mosquito and vector control. Mir Subhan Mulla (1925-2023) was the most recent honoree recognized in March 2024. Mulla received a scholarship in 1948 to attend Cornell University, where he obtained his bachelor's degree in entomology and parasitology. Mulla received his Ph.D. in entomology at the University of California, Berkeley in 1956, and then joined the University of California, Riverside (UC Riverside) faculty the same year. He retired in 2006 after 50 years of service. As one of the founding faculty in entomology at UC Riverside, Mulla created undergraduate and graduate courses and seminars in medical and veterinary entomology. As a leader in UC Riverside's world-renowned medical entomology graduate program, he advised 27 Ph.D. students, three master's students, 20 postdoctoral fellows, and 30 visiting scholars from many countries. Mulla contributed significantly to research and developments in biology, ecology, and control of arthropods of public health and economic importance, including but not limited to mosquitoes, flies, eye gnats, midges, blackflies, and stored product beetles. His work on biorational pesticides was remarkable. He published more than 550 scientific papers in peer-reviewed journals. Mulla served the scientific community as a consultant, advisor, member, or chairman with numerous national and international organizations. He guided many universities in the development of their medical entomology programs. Mulla also served as one of the founding scientists of the Society for Vector Ecology (SOVE). He also provided financial support for facilities, faculty, and students at UC Riverside. Additionally, Mulla served as a leader in the Riverside Muslim community. He and his wife Lelia founded the Islamic Society of Riverside and Orange Counties in California. In recognition of Mulla's excellence in teaching, mentorship, and research, he received numerous prestigious recognitions from universities, communities, and professional organizations. He will be greatly missed by his loving and devoted family, friends, former students, and colleagues here in the USA and abroad.

Climate Change and Vector-Borne Diseases: A Scoping Review on the Ecological and Public Health Impacts

Climate change is increasingly recognized as a significant driver of ecological and public health changes, particularly concerning vectorborne diseases. This scoping review aims to systematically map the current research on the impact of climate change on vector ecology and the subsequent effects on disease transmission dynamics. We conducted a comprehensive literature review across multiple databases to identify critical vectors, such as mosquitoes, ticks, and fleas. We examined how climate variables like temperature, precipitation, and humidity affect their populations, behaviors, and life cycles. Additionally, we explored the shifting geographic distributions of these vectors, investigating how climate change influences their spread and the emergence of diseases such as malaria, dengue, and Lyme disease in new regions. The review highlights the complex and multifaceted interactions between climate change and vector-borne diseases, emphasizing the necessity of understanding these relationships to inform effective public health strategies. Our findings indicate considerable variability in the impacts of climate change across different regions and vector species, underscoring the need for localized studies and tailored interventions. Moreover, significant research gaps were identified, particularly in predictive modeling, long-term surveillance, and the socio-economic impacts of vector-borne diseases exacerbated by climate change. We suggest directions for future research, including the development of integrated climate-health models and enhanced disease surveillance systems, to better anticipate and mitigate the effects of climate change on vector-borne disease transmission. This review underscores the urgency of addressing climate change as a critical component of global health initiatives and the importance of interdisciplinary approaches in tackling this complex issue. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 915-933

Landscape and climatic factors shaping mosquito abundance and species composition in southern Spain: A machine learning approach to the study of vector ecology

Vector-borne diseases pose significant challenges to public health, with mosquitoes acting as crucial vectors for pathogens globally. This study explores the interaction between environmental and climate factors, investigating their influence on the abundance and species composition of mosquitoes in southwestern Spain, a region endemic to several mosquito-borne diseases.Using comprehensive field data from 2020, we analysed mosquito abundance and species richness alongside remote sensing variables and modeling techniques, including the machine learning Random Forest. We collected 5859 female mosquitoes representing 13 species. Non-linear correlations were observed between mosquito abundance and climatic variables, notably temperature and rainfall. Extremely high temperatures correlated with a decrease in mosquito abundance, while accumulated rainfall in the three weeks preceding sampling positively impacted mosquito abundance by providing breeding habitats. A positive correlation between Normalized Difference Vegetation Index (NDVI) and mosquito metrics was also found, aligning with prior studies highlighting vegetation's role shaping mosquito habitats. Interestingly, a negative relationship was observed between mosquito species richness and autumn NDVI. Additionally, wind speed negatively affected mosquito species richness.This research provides valuable insights into the ecological determinants of mosquito abundance and species composition in a Mediterranean climate. These findings are crucial for understanding disease transmission dynamics and improving vector control strategies. By integrating climatic characteristics into public health interventions, management measures can become more targeted and efficient, especially during periods of heightened temperature.

Bionomics and distribution of malaria vectors in Kisumu city, Western Kenya: Implications for urban malaria transmission.

Increasing urbanization in tropical Africa may create new niches for malaria vectors, potentially leading to higher disease transmission rates. Vector control efforts remain largely targeted at ecologically rural bio-complexities with multiple hosts. Understanding mosquito species composition, ecology, host diversity and biting behavior in urban areas is crucial for planning effective control. This study assessed mosquito species diversity, abundance, behavioral patterns, and Plasmodium sporozoite infection rates of Anopheles vectors along an urban-rural transect in Kisumu city, western Kenya. Indoor and outdoor host-seeking and resting adult mosquitoes were collected using Centers for Disease Control and Prevention miniature light traps (CDC-LT) and mechanical aspirators (Prokopack) along an urban-rural transect. Females Anopheles mosquitoes collected were identified using morphological taxonomic keys to species level. Specimens belonging to the Anopheles gambiae complex and Anopheles funestus group were further processed using polymerase chain reaction (PCR) to identify members of each complex/group. Subsequently, sporozoite infection rates of the anopheline mosquitoes were determined using a multiplexed real-time quantitative PCR (qPCR) assay. A total of 3,394 female Anopheles mosquitoes were collected and identified. These comprised of An. gambiae s.l. (68%), An. funestus group (19.8%), An. coustani (7.8%), An. pharoensis (2.6%), An. maculipalipis (1.6%), and An. leesoni(0.2%). All six species were found in urban zone, but only three were found in peri-urban and rural sites. Overall, urban collections accounted for the majority of these collections (55.5%) of mosquitoes collected, followed by those from peri-urban (30%) and rural sites (14.5%). Species distribution across the three ecotypes showed Anopheles arabiensis was the dominant species in urban (84.3%) and peri-urban (89%) sites, while An. gambiae s.s. was predominantly found in the rural zone (60.2%) alongside An. arabiensis (39.7%). Anopheles funestus was the predominant species in peri-urban (98.4%) and rural (85.7%) areas, with An. leesoni accounted for 1.6% and 14.3%, respectively. In urban areas, all samples from the An. funestus group were identified as An. funestus s.s.. Majority (55.5%) of Anopheles mosquitoes were collected indoors, while secondary vectors were primarily caught outdoors. Overall, sporozoite rates were higher outdoors 3.5% compared to indoors 1.45% in rural areas. Specifically, sporozoite infectivity rates for An. funestus, An. gambiae s.s and An. arabiensis collected indoors in the rural zone was 2.5%, 1.4% and 1% respectively. Outdoors in rural areas, An. gambiae had a sporozoite rate of 5.3%, while An. arabiensis had a rate of 2.1%. In peri-urban areas An. gambiae had a sporozoite rate of 2.3%. No sporozoites were detected in samples from urban sites. The study highlights a shift of diversity of Anopheles species towards urban areas with increased outdoor activity, and significant outdoor malaria transmission in rural and peri-urban areas, emphasizing the need for tools targeting outdoor-biting mosquitoes. The presence of An. funestus in urban settings is of interest and highlights the critical importance of sustained entomological surveillance to inform integrated vector control and prevent future transmission risks.

Vector Borne Disease Ecology and Environment: Remote Sensing and GIS for Control and Management: A Systematic Review

The prevalence of vector borne disease epidemics are influenced by the thickness of the vectors persistent to climate, landscape, and environment. Historically evidenced of triggering epidemics in both vertical magnitude and horizontal spread (spatial diffusion) of increasing vector borne diseases, such as; malaria, dengue, chikungunya, Japanese encephalitis, filariasis, leishmaniases, scrub typhus, Kyasanur forest disease (KFD), West Nile virus, Lyme disease, Zika virus, and Rift valley fever in the tropical and subtropical regions, particularly, in the third world countries for the past several decades. The geographical analysis of each one VBD epidemics has a unique vector ecology and environment. The prevalence of epidemic distribution patterns and seasonal variations, and associated vector ecology were analyzed throughout the world for the past periods, in order to assess the probability of potential risk and delineate the hotspot regions susceptible to the VBD outbreaks in the country, using Remote Sensing and GIS mapping analysis. It offers a quick and efficient approach to mapping of land uses/land cover patterns and its changes over space and time, and the information on these changes linking with vector profusion and disease ecology. Vector-borne disease epidemics across the country have been evidently associated with climate factors, landscape changes, potential breeding sources; such as, water bodies, rivers, streams, and mega water resource irrigation projects, dams / reservoirs, water pools, lakes, urban agglomerations, Urban sprawl, urban dynamics, industrial developments and growths, floating population, urban migration, land use / land cover changes, wet irrigation agriculture practices, seasonal migrations on occupation, cargo shipping movements, trade and commerce, etc., and have been acted upon changing the aboriginal territories by extent of epidemic scenarios into the non-endemic regions. The integrated Earth Observation Resource Satellite data integrated with GIS has effectiveness upon proved to disease mapping, ecological niche modeling, risk assessment, spatial prediction, and offering answers to both the public health programmers and research scientists concerned on vector fecundity, and vector borne disease ecology, and thus, the geographical, ecological and environmental determinants of its range is considered to be essential for sustainable public health planning. Accordingly, prevention measures and appropriate control strategy may possibly be applied during the sporadic outbreaks situations in the new epidemic regions as well in the hot spot endemic regions regularly, so as to control the erratic transmission and prevent acceleration of epidemics early in advance successfully.

Trends and insights in dengue virus research globally: a bibliometric analysis (1995–2023)

BackgroundDengue virus (DENV) is the most widespread arbovirus. The World Health Organization (WHO) declared dengue one of the top 10 global health threats in 2019. However, it has been underrepresented in bibliometric analyses. This study employs bibliometric analysis to identify research hotspots and trends, offering a comprehensive overview of the current research dynamics in this field.ResultsWe present a report spanning from 1995 to 2023 that provides a unique longitudinal analysis of Dengue virus (DENV) research, revealing significant trends and shifts not extensively covered in previous literature. A total of 10,767 DENV-related documents were considered, with a notable increase in publications, peaking at 747 articles in 2021. Plos Neglected Tropical Diseases has become the leading journal in Dengue virus research, publishing 791 articles in this field—the highest number recorded. Our bibliometric analysis provides a comprehensive mapping of DENV research across multiple dimensions, including vector ecology, virology, and emerging therapies. The study delineates a complex network of immune response genes, including IFNA1, DDX58, IFNB1, STAT1, IRF3, and NFKB1, highlighting significant trends and emerging themes, particularly the impacts of climate change and new outbreaks on disease transmission. Our findings detail the progress and current status of key vaccine candidates, including the licensed Dengvaxia, newer vaccines such as Qdenga and TV003, and updated clinical trials. The study underscores significant advancements in antiviral therapies and vector control strategies for dengue, highlighting innovative drug candidates such as AT-752 and JNJ-1802, and the potential of drug repurposing with agents like Ribavirin, Remdesivir, and Lopinavir. Additionally, it discusses biological control methods, including the introduction of Wolbachia-infected mosquitoes and gene-editing technologies.ConclusionThis bibliometric study underscores the critical role of interdisciplinary collaboration in advancing DENV research, identifying key trends and areas needing further exploration, including host-virus dynamics, the development and application of antiviral drugs and vaccines, and the use of artificial intelligence. It advocates for strengthened partnerships across various disciplines to effectively tackle the challenges posed by DENV.

Risk of arboviral transmission and insecticide resistance status of Aedes mosquitoes during a yellow fever outbreak in Ghana

BackgroundIn late 2021, Ghana was hit by a Yellow Fever outbreak that started in two districts in the Savannah region and spread to several other Districts in three regions. Yellow fever is endemic in Ghana. However, there is currently no structured vector control programme for Aedes the arboviral vector in Ghana. Knowledge of Aedes bionomics and insecticide susceptibility status is important to control the vectors. This study therefore sought to determine Aedes vector bionomics and their insecticide resistance status during a yellow fever outbreak.MethodsThe study was performed in two yellow fever outbreak sites (Wenchi, Larabanga) and two non-outbreak sites (Kpalsogu, Pagaza) in Ghana. Immature Aedes mosquitoes were sampled from water-holding containers in and around human habitations. The risk of disease transmission was determined in each site using stegomyia indices. Adult Aedes mosquitoes were sampled using Biogents Sentinel (BG) traps, Human Landing Catch (HLC), and Prokopack (PPK) aspirators. Phenotypic resistance to permethrin, deltamethrin and pirimiphos-methyl was determined with WHO susceptibility tests using Aedes mosquitoes collected as larvae and reared into adults. Knockdown resistance (kdr) mutations were detected using allele-specific multiplex PCR.ResultsAmong the 2,664 immature Aedes sampled, more than 60% were found in car tyres. Larabanga, an outbreak site, was classified as a high-risk zone for the Yellow Fever outbreak (BI: 84%, CI: 26.4%). Out of 1,507 adult Aedes mosquitoes collected, Aedes aegypti was the predominant vector species (92%). A significantly high abundance of Aedes mosquitoes was observed during the dry season (61.2%) and outdoors (60.6%) (P < 0.001). Moderate to high resistance to deltamethrin was observed in all sites (33.75% to 70%). Moderate resistance to pirimiphos-methyl (65%) was observed in Kpalsogu. Aedes mosquitoes from Larabanga were susceptible (98%) to permethrin. The F1534C kdr, V1016I kdr and V410 kdr alleles were present in all the sites with frequencies between (0.05–0.92). The outbreak sites had significantly higher allele frequencies of F1534C and V1016I respectively compared to non-outbreak sites (P < 0.001).ConclusionThis study indicates that Aedes mosquitoes in Ghana pose a significant risk to public health. Hence there is a need to continue monitoring these vectors to develop an effective control strategy.

Adapting to the shifting landscape: Implications of climate change for malaria control: A review.

Malaria, a global public health challenge, continues to affect millions of lives, particularly in regions where its transmission is endemic. The interplay between climate change and malaria dynamics has emerged as a critical concern, reshaping the landscape of this vector-borne disease. This review publication, titled "Adapting to the shifting landscape: Implications of climate change for malaria control," explores the multifaceted relationship between climate change and the control of malaria. The paper begins by dissecting the influence of climate change on malaria dynamics, including alterations in temperature, precipitation, and other climatic factors that impact the habitat and life cycle of malaria vectors. It delves into the evolving ecology and behavior of malaria vectors in response to changing climatic conditions, emphasizing the importance of understanding these adaptations. As a response to this shifting landscape, the review discusses adaptive strategies for malaria control, ranging from vector control measures to the utilization of climate data in early warning systems. Community engagement and education are highlighted as essential components of these strategies, recognizing the vital role of local communities in effective malaria control efforts. The paper also identifies future directions and research needs, underscoring the importance of staying ahead of the evolving climate-malaria relationship. This review underscores the urgency of adapting to the changing landscape of malaria transmission driven by climate change. It emphasizes the significance of proactively addressing climate-related challenges to enhance malaria control and protect the health and well-being of vulnerable populations.

Human-Environment Interactions Shape Mosquito Seasonal Population Dynamics.

Mosquito species, including the Asian tiger mosquito, can transmit disease-causing pathogens such as dengue, Zika, and chikungunya, with their population dynamics influenced by a variety of factors including climate shifts, human activity, and local environmental conditions. Understanding these dynamics is vital for effective control measures. Our study, conducted in Jardí Botanic Marimurtra from May to November 2021, monitored Ae. albopictus activity using BG-Traps and investigated larval control effects. We employed Generalized Linear Mixed Models to analyze variables like weather, human presence, and larvicidal control on adult mosquito abundance. Adults of Ae. albopictus exhibited a seasonal pattern influenced by temperature but with bimodal peaks linked to cumulative rainfall. Proximity to stagnant water and visitor influx directly affected mosquito captures. Additionally, the effectiveness of larvicide treatments depended on interactions between preceding rainfall levels and treatment timing. Our research emphasizes the significance of studying vector ecology at local scales to enhance the efficacy of control programs and address the escalating burden of vector-borne diseases. Considering the impacts of extreme weather events and climate shifts is essential for the development of robust vector control strategies. Furthermore, our distinct findings serve as a prime illustration of utilizing statistical modeling to gain mechanistic insights into ecological patterns and processes.

Mosquito (Diptera: Culicidae) diversity and arbovirus detection across an urban and agricultural landscape

Fragmented landscapes in Mexico, characterized by a mix of agricultural, urban, and native vegetation cover, presents unique ecological characteristics that shape the mosquito community composition and mosquito-borne diseases. The extent to which landscape influences mosquito populations and mosquito-borne diseases is still poorly understood. This work assessed the effect of landscape metrics -agriculture, urban, and native vegetation cover- on mosquito diversity and arbovirus presence in fragmented tropical deciduous forests in Central Mexico during 2021. Among the 21 mosquito species across six genera we identified, Culex quinquefasciatus was the most prevalent species, followed by Aedes aegypti, Ae. albopictus, and Ae. epactius. Notably, areas with denser native vegetation cover displayed higher mosquito species richness, which could have an impact on phenomena such as the dilution effect. Zika and dengue virus were detected in 85% of captured species, with first reports of DENV in several Aedes species and ZIKV in multiple Aedes and Culex species. These findings underscore the necessity of expanding arbovirus surveillance beyond Ae. aegypti and advocate for a deeper understanding of vector ecology in fragmented landscapes to adequately address public health strategies.

Identification of Lutzomyia longipalpis' using MALDI-TOF peptide/protein profiles

Sand flies are vectors of great public health importance, since they constitute a group of hematophagous insects responsible for etiological agents transmission of zoonotic diseases such a visceral leishmaniasis. In face of the expansion of these diseases, efficient control strategies are needed which depend on comprehending the sand fly eco-epidemiology. In this regard, MALDI-TOF mass spectrometry has been used for bacteria, fungi and yeast detection studies through peptide/protein profiles. However, little is known about interference of biological factors associated with vector ecology, such as blood meal preferences and even sand fly age on the peptide/protein profiles. Thus, the present study aimed to evaluate the differences in peptide/protein profiles of the sand fly Lutzomyia longipalpis, by means of MALDI-TOF, due to the sand fly's age, sex, blood meal source and Leishmania infantum infection. Sample preparation was made removing both head and last abdomen segments keeping the thorax, its appendices and the rest of the abdomen. Five specimens per pool were used to obtain peptide/protein extract of which 1 μL solution was deposited over 1 μL MALDI matrix dried. Characteristic spectra were analyzed using principal coordinate analysis as well as indicator species analysis to discriminate differences in sand flies's peptide/protein profile by sex, age, blood meal source and L. infantum infection. The results show that the evaluated variables produced distinct peptide/protein profiles, demonstrated by the identification of specific diagnostic ions. It was found that the interference of biological factors should be taken into account when using the MALDI-TOF analysis of sand fly species identification and eco-epidemiological applications in field studies. Based on our results, we believe that it is possible to identify infected specimens and the source of blood meal in a collection of wild sand flies, serving to measure infectivity and understand the dynamics of the vector's transmission chain. Our results may be useful for epidemiological studies that look at the ecology of sand flies and leishmaniasis, as well as for raising awareness of biological characteristics’ impact on peptide/protein profiles in sand fly species identification.

Mosquito Vector Ecology in Swamp Ecosystems

This study investigates the ecological dynamics of mosquito vectors in the swamp ecosystems of Desa Kebun Raya, Kecamatan Kintap, Kabupaten Tanah Laut, Kalimantan Selatan. An entomological survey was conducted to assess species composition, abundance, and larval indices in relation to the unique swamp habitat. Four mosquito species were identified: Culex quinquefasciatus, Culex tritaeniorhynchus, Aedes aegypti, and Aedes albopictus. The dominance of Culex species, particularly C. quinquefasciatus, suggests a strong adaptation to the swamp environment. Larval indices indicated a high risk of vector-borne disease transmission, with a House Index (HI) of 35%, Container Index (CI) of 0.14%, and Breteau Index (BI) of 64%. The study highlights the complex interactions between swamp ecology, mosquito population dynamics, and potential disease transmission risks in this understudied region of Indonesia.

Malaria Vector Bionomics: Countrywide Surveillance Study on Implications for Malaria Elimination in India.

The biological characteristics of mosquito vectors vary, impacting their response to control measures. Thus, having up-to-date information on vector bionomics is essential to maintain the effectiveness of existing control strategies and tools, particularly as India aims for malaria elimination by 2030. This study aims to assess the proportions of vector species resting indoors and outdoors, determine their preference for host biting/feeding, identify transmission sites, and evaluate the susceptibility of vectors to insecticides used in public health programs. Mosquito collections were conducted in 13 districts across 8 Indian states from 2017 to 2020 using various methods to estimate their densities. Following morphological identification in the field, sibling species of Anopheles mosquitoes were identified molecularly using polymerase chain reaction (PCR)-specific alleles. Plasmodium falciparum and Plasmodium vivax infections in the vectors were detected using enzyme-linked immunosorbent assay (ELISA) and PCR assays. In addition, we assessed the insecticide susceptibility status of primary malaria vectors following the World Health Organization (WHO) protocol. Anopheles culicifacies, a primary malaria vector, was collected (with a man-hour density ranging from 3.1 to 15.9) from all states of India except those in the northeastern region. Anopheles fluviatilis, another primary vector, was collected from the states of Madhya Pradesh, Maharashtra, Karnataka, and Odisha. In Haryana and Karnataka, An. culicifacies sibling species A predominated, whereas species C and E were predominant in Madhya Pradesh and Maharashtra. An. culicifacies displayed mainly endophilic behavior across all states, except in Madhya Pradesh, where the proportion of semigravid and gravid mosquitoes was nearly half of that of unfed mosquitoes. The human blood index of An. culicifacies ranged from 0.001 to 0.220 across all study sites. The sporozoite rate of An. culicifacies ranged from 0.06 to 4.24, except in Madhya Pradesh, where none of the vector mosquitoes were found to be infected with the Plasmodium parasite. In the study area, An. culicifacies exhibited resistance to DDT (dichlorodiphenyltrichloroethane; with <39% mortality). Moreover, it showed resistance to malathion (with mortality rates ranging from 49% to 78%) in all districts except Angul in Odisha and Palwal in Haryana. In addition, resistance to deltamethrin was observed in districts of Maharashtra, Gujarat, Haryana, and Karnataka. Our study offers vital insights into the prevalence, resting behavior, and sibling species composition of malaria vectors in India. It is evident from our findings that resistance development in An. culicifacies, the primary vector, to synthetic pyrethroids is on the rise in the country. Furthermore, the results of our study suggest a potential change in the resting behavior of An. culicifacies in Madhya Pradesh, although further studies are required to confirm this shift definitively. These findings are essential for the development of effective vector control strategies in India, aligning with the goal of malaria elimination by 2030.