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Investigating Morphological And Molecular Identifiers For Culex Restuans And Culex Pipiens From Central Illinois, Savannah L. Ettien

Masters Theses

Some of the most prominent vectors for West Nile Virus are mosquitoes of the genus Culex. As a result, efforts have been made to monitor the spread of Culex species as climate change has allowed them to travel to places that they never inhabited before. Since Cx. restuans is a less prevalent vector, most studies for prevention focus on Cx. pipiens, which is the primary vector for the spread of West Nile Virus in the Midwestern United States, especially in the late summer and early fall seasons. As both species share many morphological characteristics and are present at …

How Sewage Pollution Affects Distribution And Life History Traits Of The Southern House Mosquito, Culex Quinquefasciatus, Catherine Dean Bermond

Master's Theses

Eutrophication from wastewater can cause fluxes of nutrients like and carbon and nitrogen in urban waters. One source of nitrogen in freshwater is from untreated sewage discharging from septic tanks. This causes a variety of environmental issues including harmful algal blooms, harming natural predators, and increased production of mosquitoes. Culex quinquefasciatus is the vector of West Nile Virus in St. Tammany Parish, Louisiana. St. Tammany Parish has over 600 miles of septic ditches, which receive effluent directly from aerated treatment units. Culex quinquefasciatus oviposit in polluted waters, and larvae perform well in water with high levels of decomposing organic matter. …

Hide And Seek: An Exploration Of Antipredator And Predator Avoidance Mechanisms In Orthopodomyia Signifera In Response To Predation From Toxorhynchites Rutilus, Nathaniel Dahlberg

Master's Theses

There have been many observations of larval Orthopodomyia signifera coexisting with the predator Toxorhynchites rutilus. There are three hypotheses that could explain how Or. signifera resists predation from Tx. rutilus. The first hypothesis states that larvae adapt behavioral changes that limit predation. The second hypothesis states thoracic setae serve as a physical defense that prevents Tx. rutilus from grasping Or. signifera. The third hypothesis states Or. signifera possess a chemical defense indicated by aposematic coloration. To test the first hypothesis larval Or. signifera were exposed to conspecific and heterospecific predation cues and their behavior was observed. Both cues …

Esterase Mediated Insecticide Resistance In The Southern House Mosquito, Culex Quinquefasciatus, Vivek Pokhrel

LSU Doctoral Dissertations

Much is known about the development of insecticide resistance associated with targeted application against insect populations. However, off-target selection by applications of insecticides in agricultural and residential sites also impacts development of insecticide resistance and is understudied. Similarly, the impact of selecting one life stage of mosquitoes on the insecticide susceptibility of different life stages is largely unknown. The first part of this study shows that susceptibility to chlorantraniliprole, which is applied in rice and sugarcane fields in LA, decreased (5.7 to12-fold) in populations of Culex quinquefasciatus collected from near these fields compared to a reference field strain. In addition, …

The Risks Posed By Mosquito Ultra-Low Volume Applications To Procambarus Clarkii Production, Timothy Mcnamara

LSU Doctoral Dissertations

Mosquito abatement has received much scrutiny due to concerns about the impacts of control applications on non-target organisms. In Louisiana, a great deal of this concern has come from crawfish farmers claiming mosquito abatement applications have damaged crawfish production. To determine which mosquito abatement practices and products pose a risk to crawfish production, we conducted a series of studies examining mosquito abatement practices in the vicinity of crawfish production fields and the impacts of common mosquito abatement product exposure on crawfish health and production. We found that mosquito ULV applications are the most likely to result in exposure to crawfish …

Elevated Substitution Rates Among Wolbachia-Infected Mosquito Species Results In Apparent Phylogenetic Discordance., James E. Russell, Michael Saum, Rebekah Williams

Georgia Journal of Science

As one of the most widely distributed bacterial cytoplasmic symbionts on earth, Wolbachia pipientis Hertig serves as a model organism for the understanding of host-symbiont interactions. Many mosquito species are infected with Wolbachia strains that induce a form of reproductive manipulation called cytoplasmic incompatibility, in which infected females gain a reproductive advantage over uninfected females in mixed infection populations. The selective advantage of cytoplasmic incompatibility often results in a population sweep of Wolbachia and co-transmitted mitochondrial genomes. Mitochondrial evolution and phylogenetic inferences drawn from mitochondrial gene sequences are thus potentially compromised by reproductive manipulating symbionts, like Wolbachia. Our initial …

Spatial And Temporal Variation In Aedes Albopictus Prevalence Across Arkansas, Alyssa N. Jones, Eric C. Lovely, Douglas G. Barron

Journal of the Arkansas Academy of Science

Aedes albopictus is a well-known vector species of mosquito that is responsible for the transmission of many arboviruses such as Zika, chikungunya, and dengue. The objective of this study was to quantify spatial and temporal variation of Ae. albopictus prevalence in Arkansas. We used egg abundance as a proxy for mosquito prevalence. Across 2 years, we worked with the Arkansas Department of Health to collect mosquito eggs using oviposition traps. Eggs were desiccated, counted, and later rehydrated in rearing chambers and raised through adulthood for species determination (>99% Ae. albopictus). We determined mean egg abundance by month, year, …

Mosquito Microbiomes: Understanding The Interface Between Microbiome, Environment, And Human Pathogens, Amanda G. Tokash-Peters

Graduate Doctoral Dissertations

The study of mosquito microbiomes promises a deeper understanding of factors influencing interactions between mosquito hosts, human pathogens, and the environment. While several studies have focused on tripartite interactions between host, pathogen, and microbiome, far fewer have analyzed the environmental factors that shape these interactions and provide the basis for the formation of microbial communities in the mosquito host. Additionally, the use of Wolbachia and similar anti-arboviral symbionts in mosquitoes to control pathogen transmission has emerged as a popular idea for mosquito control and requires further investigation. The works presented here address changes in mosquito microbiomes, including the abundance of …

Do Mosquito Pesticides Harm Their Natural Enemies? Ecological Impacts And Non-Target Effects Of Larvicides On Mosquito Predators, Joseph Nelsen

Master's Theses

Larvicides are chemicals used to kill juvenile mosquitoes. When applied to an area, other aquatic organisms are exposed to these chemicals. The removal or impairment of top insect predators could be beneficial to mosquito populations once harmful pesticide levels dissipate. Two common larvicides were examined: growth regulators (IGRs) and surface films (SFs). The goal of this project was to determine if larvicides harm mosquito predators common to southern Mississippi. I surveyed aquatic sites before and after IGR and SF treatments, and then compared changes in insect community structure. Community evenness was lower in SF treated habitats. When analyzing prey taxa …

From Field To Film: Mosquito Surveillance And Survey Of Us Adults' Knowledge And Attitudes Towards Arthropod-Borne Disease Vectors, Justine Laviolette

Department of Entomology: Dissertations, Theses, and Student Research

Mosquito-borne disease is a public health challenge that warrants an active surveillance program for the identification of mosquito populations and the education of the public for prevention and protection against disease-transmitting arthropods. The communication of science to the public is necessary to prevent disease, change behavior, and promote a dialog between scientists and the public.

People are accustomed to high quality entertainment, which begs the question, “If we made science more entertaining, would the public be more interested?”

To address these issues, the objectives of this study are: 1) identify mosquito species and abundance at the US Meat Animal Research …

Mosquito Diversity And Positive Pools For The West Nile Virus In Forested Versus Non-Forested Areas, Elizabeth C. Paul

Honors Projects

The West Nile virus (WNV) is one of the leading causes of mosquito borne illness in the United States (CDC, 2018). This virus is a neurotropic pathogen that can cause fever and encephalitis. It is known that the Culex species is the primary vector for WNV. Humans infected with the WNV are typically asymptomatic. There is a small portion of individuals that experience West Nile fever which could include symptoms like high fever, vision loss, and coma (CDC, 2018). Previous studies have shown that mosquitoes tend to favor forests and wetlands (Hay et al., 1998), however, it is unknown if …

Bacteria-Mediated Modification Of Insecticide Toxicity In The Yellow Fever Mosquito, Aedes Aegypti, Sara S. Scates, Scott T. O'Neal, Troy D. Anderson

Department of Entomology: Faculty Publications

The incidence of mosquito-borne disease poses a significant threat to human and animal health throughout the world, with effective chemical control interventions limited by widespread insecticide resistance. Recent evidence suggests that gut bacteria of mosquitoes, known to be essential in nutritional homeostasis and pathogen defense, may also play a significant role in facilitating insecticide resistance. This study investigated the extent to which bacteria contribute to the general esterase and cytochrome P450 monooxygenase (P450)-mediated detoxification of the insecticides propoxur and naled, as well as the insecticidal activity of these chemistries to the yellow fever mosquito, Aedes aegypti. Experiments conducted using …

Mosquito Image Classification Using Convolutional Neural Networks, Sumanth Vissamsetty

LSU Master's Theses

Human life has always been affected by insects, especially mosquitoes, since it's early beginnings. This pesky insect acts as a vector that transmit pathogens through feeding on our blood, spreading life-threatening diseases like Zika Virus, Malaria, Dengue fever, Chikungunya and more. It is important to prevent these mosquitoes from harming humans and one way to do so is to control the mosquito population, or mosquito abatement as it is commonly known. It is important to note that not all mosquitoes are the same and each of them live, reproduce and attack in their own unique way. Hence it is crucial …

Effects Of Dietary Sugars And Sugar Alcohols On Mortality And Thermal Tolerance In Culex Quinquefasciatus And Aedes Aegypti, Madeleine Chura

LSU Master's Theses

Aedes aegypti (L. 1762), the yellow fever mosquito, and Culex quinquefasciatus Say 1823, the southern house mosquito, are prevalent in tropical and subtropical areas worldwide and are responsible for the spread of a number of devastating diseases to humans and livestock. The development of new control methods, as well as continued study of mosquito biology, is vital for improving human health. This study aimed to examine the efficacy of sugar alcohols as a novel means for mosquito control, as well as how sugar alcohols and other factors are involved in thermal tolerance in mosquitoes.

No-choice tests with the sugar alcohols …

Vapor Delivery Of Plant Essential Oils Alters Pyrethroid Efficacy And Detoxification Enzyme Activity In Mosquitoes, Scott T. O'Neal, Ellis J. Johnson, Leslie Catherine Rault, Troy D. Anderson

Department of Entomology: Faculty Publications

The use of synthetic insecticides to limit the spread of mosquito-borne disease faces a number of significant challenges, including insecticide resistance, concerns related to the environmental impact of widespread insecticide use, as well as slowed development of new insecticide chemistries. One important alternative to broadcast insecticides is the use of personal protection strategies to limit contact with vector species, including the use of spatial repellents that can employ synthetic pyrethroids or botanical products to effect control. A currently underexplored area of research involves the investigation of botanical products for their potential to serve as insecticide synergists when delivered as a …

Investigating The Role Of Coyotes, Canis Latrans, In The Spread Of Parasites And Arthropod-Borne Diseases In Georgia, Usa., Ansleigh Banks

Electronic Theses and Dissertations

In order to analyze the role of coyotes, Canis latrans, as hosts of parasites and arthropod-borne diseases in the state of Georgia, USA, 38 coyotes representing 18 counties and multiple geographic regions of the state were dissected and analyzed for the presence of Dirofilaria immitis, intestinal parasites, ectoparasites, and tick-borne illnesses. Mosquitoes from the locations which the coyotes originated were trapped and analyzed for the presence of D. immitis larvae. In compliance with IACUC guidelines, coyotes were obtained from individuals who had previously hunted or trapped the coyotes for leisure. Parasites were identified based on morphological features with the use …

Ecological Stoichiometry: What Role Does It Play In The Competition And Spatial Distribution Patterns Of Aedes Albopictus And Aedes Aegypti?, James Deerman

Master's Theses

Ecological stoichiometry is the balance of chemical substances within animal bodies through interactions and processes within their ecosystem. Though relatively underexplored, it provides a wealth of information linking interactions across different levels of organization. Detritus is the base of the food web within the small aquatic ecosystems occupied by the mosquitoes Aedes albopictus and Aedes aegypti. Nutrient content of detritus varies, but it can have a negative effect on mosquito growth and survival if nutrient thresholds are not met. I investigated nutrient environments and species abundance in cemetery vases in New Orleans, LA to assess detrital heterogeneity and its …

The Effects Of Juvenile Exposure To Sub-Lethal Concentrations Of Pesticides On The Adult Reproductive Biology Of The Male Southern House Mosquitoe, Culex Quinquefasciatus, Shiloh Dean Judd

LSU Master's Theses

Mosquitoes transmit pathogens capable of causing significant diseases, the worst of which can permanently disfigure or kill. Mosquito control efforts can be strengthened by better understanding all aspects of mosquito biology, but there is deficient information regarding sperm production in male mosquitoes. Understanding the sperm production and capacity of vector species may reveal new control strategies.

The goal of this research was to determine if larval exposure to sub-lethal concentrations, defined as killing less than half of the sample population, of pesticides negatively impacts the adult male reproductive health of the southern house mosquito, Culex quinquefasciatus Say. This study quantified …

Molecular Candidates For Blocking The Transmission Of Vector-Borne Diseases, Ashish Naresh Vora

Biological Sciences Theses & Dissertations

Vector-borne diseases (VBDs) require urgent attention as they have a high mortality rate, with 700,000 people dying in a year as of 2017. So far, extremely few reliable vaccination strategies and solutions have emerged. Transmission blocking vaccines are one among many solutions available to manage the control of VBDs. These require identification of both vector and pathogen molecules that play important roles in the transmission, dissemination and establishment of VBDs. Our strategy is to characterize these candidates that play important roles in vector-host-pathogen interactions. This manuscript presents two such studies identifying the participation of two arthropod molecules in vector-host-pathogen interactions. …

A Highly Stable Blood Meal Alternative For Rearing Aedes And Anopheles Mosquitoes, Ted Baughman, Chelsea Peterson, Corrie Ortega, Sarah R. Preston, Christopher Paton, Jessica Williams, Amy Guy, Gavin Omodei, Brian Johnson, Helen Williams, Scott L. O'Neill, Scott A. Ritchie, Stephen L. Dobson, Damian Madan

Entomology Faculty Publications

We investigated alternatives to whole blood for blood feeding of mosquitoes with a focus on improved stability and compatibility with mass rearing programs. In contrast to whole blood, an artificial blood diet of ATP-supplemented plasma was effective in maintaining mosquito populations and was compatible with storage for extended periods refrigerated, frozen, and as a lyophilized powder. The plasma ATP diet supported rearing of both Anopheles and Aedes mosquitoes. It was also effective in rearing Wolbachia-infected Aedes mosquitoes, suggesting compatibility with vector control efforts.

Improving Aedes Mosquito Surveillance And La Crosse Virus Screening In Eastern Tennessee, Cassandra Urquhart

Masters Theses

La Crosse virus (LACV), transmitted by infected Aedes triseriatus, Ae. albopictus, and Ae. japonicus mosquitoes is the leading cause of pediatric arboviral encephalitis. Severe cases of LAC encephalitis occur in individuals 16-years-old or younger and may cause permanent neurological damage or fatality. No vaccines exist making mosquito control and disease prevention crucial to public health. Effective screening and surveillance practices are key components to these goals. While a number of standard mosquito surveillance methods exist, continuous testing and improved understanding of vector biology to determine the best ways to implement these methods is important. Additionally, the current standard …

Hemocyte Differentiation Mediates The Mosquito Late-Phase Immune Response Against Plasmodium In Anopheles Gambiae, Ryan C. Smith, Carolina Barillas-Mury, Marcelo Jacobs-Lorena

Ryan C. Smith

Plasmodium parasites must complete development in the mosquito vector for transmission to occur. The mosquito innate immune response is remarkably efficient in limiting parasite numbers. Previous work has identified a LPS-induced TNFα transcription factor (LITAF)-like transcription factor, LITAF-like 3 (LL3), which significantly influences parasite numbers. Here, we demonstrate that LL3 does not influence invasion of the mosquito midgut epithelium or ookinete-to-oocyst differentiation but mediates a late-phase immune response that decreases oocyst survival. LL3 expression in the midgut and hemocytes is activated by ookinete midgut invasion and is independent of the mosquito microbiota, suggesting that LL3 may be a component of …

Carbon Dioxide Sensitivity In Two Disjunct Populations Of The Pitcher-Plant Mosquito, Wyeomyia Smithii, Daniel L. Allen Jr.

Honors College Theses

The pitcher-plant mosquito, Wyeomyia smithii, utilizes carbon dioxide receptors primarily on their maxillary palps to seek potential hosts for blood meals. Two disjunct populations of W. smithii were analyzed to test for differences in carbon dioxide sensitivity that would correlate to varying levels of autogeny, ranging from the autogenous Northern populations (from North Carolina through Canada) to the anautonenous Southern populations (Florida – Louisiana), with the Georgia population exhibiting a shift from autogeny to anautogeny over the past two decades. I compared Georgia (Tattnall Co.) and Florida populations using blood feeding assays and olfactometry assays. Willingness to blood feed …

Sewer Overflows And The Vector Mosquito Proximity To Human West Nile Virus Infections, Andrea Simone Bowers

Walden Dissertations and Doctoral Studies

DeKalb and Fulton Counties, which share the metropolitan Atlanta area, have seen an increase in West Nile infected vector mosquitoes; the increase is associated with close proximity to combined sewer overflow facilities. Despite completion of the remediation system in 2008, the mosquito population testing positive for West Nile virus has increased each year from 2010 through 2012. Guided by the Geographical Information System framework and using spatial analysis and regression analyses, this study described and quantified the relationship between sewer system overflows and amplification of vector mosquitoes; an additional goal was to investigate their proximity to human cases of West …

Characterization Of Juvenile Hormone Biosynthetic Enzymes In The Mosquito, Aedes Aegypti, Pratik Nyati

FIU Electronic Theses and Dissertations

The juvenile hormones (JHs) are sesquiterpenoid compounds that play a central role in insect reproduction, development and behavior. They are synthesized and secreted by a pair of small endocrine glands, the corpora allata (CA), which are intimately connected to the brain. The enzymes involved in the biosynthesis of JH are attractive targets for the control of mosquito populations. This dissertation is a comprehensive functional study of five Aedes aegypti CA enzymes, HMG-CoA synthase (AaHMGS), mevalonate kinase (AaMK), phosphomevalonate kinase (AaPMK), farnesyl diphosphate synthase (AaFPPS) and farnesyl pyrophosphate phosphatase (AaFPPase).

The …

The Plasmodium Bottleneck: Malaria Parasite Losses In The Mosquito Vector, Ryan C. Smith, Joel Vega-Rodríguez, Marcelo Jacobs-Lorena

Ryan C. Smith

Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission.

Regulation Of Anti-Plasmodium Immunity By A Litaf-Like Transcription Factor In The Malaria Vector Anopheles Gambiae, Ryan C. Smith, Abraham G. Eappen, Andrea J. Radtke, Marcelo Jacobs-Lorena

Ryan C. Smith

The mosquito is the obligate vector for malaria transmission. To complete its development within the mosquito, the malaria parasite Plasmodium must overcome the protective action of the mosquito innate immune system. Here we report on the involvement of the Anopheles gambiae orthologue of a conserved component of the vertebrate immune system, LPS-induced TNFα transcription factor (LITAF), and its role in mosquito anti-Plasmodium immunity. An. gambiae LITAF-like 3 (LL3) expression is up-regulated in response to midgut invasion by both rodent and human malaria parasites. Silencing of LL3 expression greatly increases parasite survival, indicating that LL3 is part of an anti-Plasmodium defense …

West Nile Virus In Utah, Erin Hodgson

All Current Publications

West Nile Virus (WNV) was first detected in Uganda in 1937. For several years, WNV remained relatively contained in Africa, Europe and the Middle East.

The Effects Of Spinosad On Culex Quinquefasciatus (Diptera: Culicidae) And Non-Target Insect Species, Owen Mcbride Jones

LSU Master's Theses

Spinosad is a relatively new insecticide with a unique mode of action that is being evaluated for control of larval mosquitoes. Whereas a number of toxicological studies have measured effects of spinosad on various mammals, fish, birds, and terrestrial arthropods, fewer studies have been conducted on the effects of spinosad on non-target aquatic insect species. Such studies are important as these species might be found in the same environments as mosquito larvae targeted for control. A neighborhood pond was surveyed to find a representative species of mosquito as well as other common aquatic insects with which to examine susceptibility to …

Transfected Mosquito Vectors, Stephen L. Dobson

Entomology Faculty Patents

A method is provided for producing an artificial infection in a Culicidae (mosquito) species. The mosquitoes include species within the subfamilies Culicinae and Anophelinae, and the species include Aedes albopictus, Aedes aegypti and Aedes polynesiensis infected with a Wolbachia infection. The infection may be a strain of Wolbachia which does not normally or naturally infect the selected mosquito species. The artificially infected Aedes mosquito can be introduced into a mosquito population to control the reproduction capability of the population by introducing an incompatible Wolbachia infection. The present method can be used as a novel means to limit mosquito-borne pathogens and …