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- Kenya (7)
- Glossina (6)
- Trypanosoma brucei (6)
- Trypanosomiasis (6)
- Trypanosomosis (6)
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- Tsetse (6)
- Rift Valley fever (5)
- Trypanosoma congolense (5)
- Cattle (4)
- Infectivity (4)
- Prevalence (4)
- Trypanosomes (4)
- Tsetse flies (4)
- Epidemiology (3)
- Sleeping sickness (3)
- Trypanosoma vivax (3)
- Trypsin (3)
- Tsetse fly (3)
- Africa (2)
- Basic reproduction number (2)
- Entomology (2)
- Glossina morsitans morsitans (2)
- Glossina pallidipes (2)
- Lectin (2)
- Midgut lectin (2)
- Mosquito vectors (2)
- Nagana (2)
- Rickettsia (2)
- Trypanosoma simiae (2)
- Trypanotolerance (2)
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Articles 31 - 60 of 83
Full-Text Articles in Animal Diseases
Comparative Genomic Analysis Of Six Glossina Genomes, Vectors Of African Trypanosomes, Geoffrey M. Attardo, Adly M.M. Abd-Alla, Alvaro Acosta-Serrano, James E. Allen, Rosemary Bateta, Joshua B. Benoit, Kostas Bourtzis, Jelle Caers, Guy Caljon, Mikkel B. Christensen, David W. Farrow, Markus Friedrich, Aurélie Hua-Van, Emily C. Jennings, Denis M. Larkin, Daniel Lawson, Michael J. Lehane, Vasileios P. Lenis, Ernesto Lowy-Gallego, Rosaline W. Macharia, Anna R. Malacrida, Heather G. Marco, Daniel Masiga, Gareth L. Maslen, Irina Matetovici, Richard P. Meisel, Irene Meki, Veronika Michalkova
Comparative Genomic Analysis Of Six Glossina Genomes, Vectors Of African Trypanosomes, Geoffrey M. Attardo, Adly M.M. Abd-Alla, Alvaro Acosta-Serrano, James E. Allen, Rosemary Bateta, Joshua B. Benoit, Kostas Bourtzis, Jelle Caers, Guy Caljon, Mikkel B. Christensen, David W. Farrow, Markus Friedrich, Aurélie Hua-Van, Emily C. Jennings, Denis M. Larkin, Daniel Lawson, Michael J. Lehane, Vasileios P. Lenis, Ernesto Lowy-Gallego, Rosaline W. Macharia, Anna R. Malacrida, Heather G. Marco, Daniel Masiga, Gareth L. Maslen, Irina Matetovici, Richard P. Meisel, Irene Meki, Veronika Michalkova
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Background: Tsetse flies (Glossina sp.) are the vectors of human and animal trypanosomiasis throughout sub-Saharan Africa. Tsetse flies are distinguished from other Diptera by unique adaptations, including lactation and the birthing of live young (obligate viviparity), a vertebrate blood-specific diet by both sexes, and obligate bacterial symbiosis. This work describes the comparative analysis of six Glossina genomes representing three sub-genera: Morsitans (G. morsitans morsitans, G. pallidipes, G. austeni), Palpalis (G. palpalis, G. fuscipes), and Fusca (G. brevipalpis) which represent different habitats, host preferences, and vectorial capacity. Results: Genomic analyses validate established evolutionary relationships and sub-genera. Syntenic analysis of Glossina relative …
Host Species And Site Of Collection Shape The Microbiota Of Rift Valley Fever Vectors In Kenya, David P. Tchouassi, Ephantus J. Muturi, Samwel O. Arum, Chang Hyun Kim, Christopher J. Fields, Baldwyn Torto
Host Species And Site Of Collection Shape The Microbiota Of Rift Valley Fever Vectors In Kenya, David P. Tchouassi, Ephantus J. Muturi, Samwel O. Arum, Chang Hyun Kim, Christopher J. Fields, Baldwyn Torto
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The composition and structure of microbial communities associated with mosquitoes remain poorly understood despite their important role in host biology and potential to be harnessed as novel strategies for mosquito-borne disease control. We employed MiSeq sequencing of the 16S rRNA gene amplicons to characterize the bacterial flora of field-collected populations of Aedes mcintoshi and Aedes ochraceus, the primary vectors of Rift Valley fever (RVF) virus in Kenya. Proteobacteria (53.5%), Firmicutes (22.0%) and Actinobacteria (10.0%) were the most abundant bacterial phyla accounting for 85.5% of the total sequences. Non-metric multi-dimensional scaling plots based on Bray-Curtis dissimilarities revealed a clear grouping of …
Geospatial Analysis Of Rickettsial Species, Amy Frank
Geospatial Analysis Of Rickettsial Species, Amy Frank
Animal Science Undergraduate Honors Theses
Rickettsia species are obligate intracellular, arthropod-borne bacteria with a potential to cause multiple diseases including Rocky Mountain spotted fever (RMSF). Fleas, mites, and ticks serve as vectors for Rickettsia, but ticks are the primary vector of interest. RMSF and other rickettsial diseases have continued to gain importance in both human and veterinary medicine as RMSF is the most common tick-borne disease within the United States according to the Lyme and Tick-Borne Disease Research Center. A statewide citizen science project was utilized to determine the prevalence of Spotted Fever Group (SFG) Rickettsia in Arkansas. This project yielded results in 64 …
Sodalis Glossinidius Presence In Wild Tsetse Is Only Associated With Presence Of Trypanosomes In Complex Interactions With Other Tsetse-Specific Factors 06 Biological Sciences 0604 Genetics, Manun Channumsin, Marc Ciosi, Dan Masiga, C. Michael R. Turner, Barbara K. Mable
Sodalis Glossinidius Presence In Wild Tsetse Is Only Associated With Presence Of Trypanosomes In Complex Interactions With Other Tsetse-Specific Factors 06 Biological Sciences 0604 Genetics, Manun Channumsin, Marc Ciosi, Dan Masiga, C. Michael R. Turner, Barbara K. Mable
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Background: Susceptibility of tsetse flies (Glossina spp.) to trypanosomes of both humans and animals has been associated with the presence of the endosymbiont Sodalis glossinidius. However, intrinsic biological characteristics of the flies and environmental factors can influence the presence of both S. glossinidius and the parasites. It thus remains unclear whether it is the S. glossinidius or other attributes of the flies that explains the apparent association. The objective of this study was to test whether the presence of Trypanosoma vivax, T. congolense and T. brucei are related to the presence of S. glossinidius in tsetse flies when other factors …
Enhancing Vector Refractoriness To Trypanosome Infection: Achievements, Challenges And Perspectives, Henry M. Kariithi, Irene K. Meki, Daniela I. Schneider, Linda De Vooght, Fathiya M. Khamis, Anne Geiger, Guler Demirbaş-Uzel, Just M. Vlak, Ikbal Agah Ince, Sorge Kelm, Flobert Njiokou, Florence N. Wamwiri, Imna I. Malele, Brian L. Weiss, Adly M.M. Abd-Alla
Enhancing Vector Refractoriness To Trypanosome Infection: Achievements, Challenges And Perspectives, Henry M. Kariithi, Irene K. Meki, Daniela I. Schneider, Linda De Vooght, Fathiya M. Khamis, Anne Geiger, Guler Demirbaş-Uzel, Just M. Vlak, Ikbal Agah Ince, Sorge Kelm, Flobert Njiokou, Florence N. Wamwiri, Imna I. Malele, Brian L. Weiss, Adly M.M. Abd-Alla
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With the absence of effective prophylactic vaccines and drugs against African trypanosomosis, control of this group of zoonotic neglected tropical diseases depends the control of the tsetse fly vector. When applied in an area-wide insect pest management approach, the sterile insect technique (SIT) is effective in eliminating single tsetse species from isolated populations. The need to enhance the effectiveness of SIT led to the concept of investigating tsetse-trypanosome interactions by a consortium of researchers in a five-year (2013-2018) Coordinated Research Project (CRP) organized by the Joint Division of FAO/IAEA. The goal of this CRP was to elucidate tsetse-symbiome-pathogen molecular interactions …
Molecular Survey For The Honey Bee Trypanosome Parasites Crithidia Mellificae And Lotmaria Passim, Mary-Kate Williams
Molecular Survey For The Honey Bee Trypanosome Parasites Crithidia Mellificae And Lotmaria Passim, Mary-Kate Williams
Graduate Theses and Dissertations
Honey bee populations have been fluctuating within recent years. No one cause has been attributed to colony fluctuations due to the theory that multiple stressors interact with one another to impact colony health. Consequently, microorganisms such as internal parasites of honey bees have been understudied as a contributor to colony health decline.
Molecular diagnostics were utilized to detect the presence of two honey bee trypanosome parasites, Crithidia mellificae and Lotmaria passim, in managed and feral honey bee populations from eight states in the United States (USA). Because studies on trypanosome infections are lacking in the USA, it is important to …
Datasets For Mapping Pastoralist Movement Patterns And Risk Zones Of Rift Valley Fever Occurrence, Gladys Mosomtai, Magnus Evander, Charles Mundia, Per Sandström, Clas Ahlm, Osama Ahmed Hassan, Olivia Wesula Lwande, Moses K. Gachari, Tobias Landmann, Rosemary Sang
Datasets For Mapping Pastoralist Movement Patterns And Risk Zones Of Rift Valley Fever Occurrence, Gladys Mosomtai, Magnus Evander, Charles Mundia, Per Sandström, Clas Ahlm, Osama Ahmed Hassan, Olivia Wesula Lwande, Moses K. Gachari, Tobias Landmann, Rosemary Sang
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Rift Valley fever (RVF) is a zoonotic disease affecting humans and animals. It is caused by RVF virus transmitted primarily by Aedes mosquitoes. The data presented in this article propose environmental layers suitable for mapping RVF vector habitat zones and livestock migratory routes. Using species distribution modelling, we used RVF vector occurrence data sampled along livestock migratory routes to identify suitable vector habitats within the study region which is located in the central and the north-eastern part of Kenya. Eleven herds monitored with GPS collars were used to estimate cattle utilization distribution patterns. We used kernel density estimator to produce …
Haematology Of N’Dama And West African Shorthorn Cattle Herds Under Natural Trypanosoma Vivax Challenge In Ghana, Ebenezer Yaw Ganyo, Johnson N. Boampong, Daniel K. Masiga, Jandouwe Villinger, Paa Kobina Turkson
Haematology Of N’Dama And West African Shorthorn Cattle Herds Under Natural Trypanosoma Vivax Challenge In Ghana, Ebenezer Yaw Ganyo, Johnson N. Boampong, Daniel K. Masiga, Jandouwe Villinger, Paa Kobina Turkson
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Background: Animal trypanosomosis is a major cause of economic loss in livestock production in Africa. A suggested control measure is to use breeds with traits of trypanotolerance. The study examines the effect of natural Trypanosoma vivax challenge on haematological parameters in two trypanotolerant cattle [N’Dama and West African Shorthorn (WASH)] herds. Methods: Trypanosoma vivax-specific primers were used to diagnose T. vivax infection in an N’Dama herd at Cape Coast in southern Ghana and a WASH herd at Chegbani in northern Ghana from May to July 2011 in a cross-sectional study. Levels of haematological parameters comprising packed cell volume (PCV), haemoglobin …
The Role Of Hyalomma Truncatum On The Dynamics Of Rift Valley Fever: Insights From A Mathematical Epidemic Model, Sansao A. Pedro, Shirley Abelman, Henri E.Z. Tonnang
The Role Of Hyalomma Truncatum On The Dynamics Of Rift Valley Fever: Insights From A Mathematical Epidemic Model, Sansao A. Pedro, Shirley Abelman, Henri E.Z. Tonnang
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To date, our knowledge of Rift Valley fever (RVF) disease spread and maintenance is still limited, as flooding, humid weather and presence of biting insects such as mosquitoes, have not completely explained RVF outbreaks. We propose a model that includes livestock, mosquitoes and ticks compartments structured according to their questing and feeding behaviour in order to study the possible role of ticks on the dynamics of RVF. To quantify disease transmission at the initial stage of the epidemic, we derive an explicit formula of the basic reproductive number, R0. Using the concept of Metzler matrix, we state necessary conditions for …
Distribution And Abundance Of Key Vectors Of Rift Valley Fever And Other Arboviruses In Two Ecologically Distinct Counties In Kenya, Rosemary Sang, Samwel Arum, Edith Chepkorir, Gladys Mosomtai, Caroline Tigoi, Faith Sigei, Olivia Wesula Lwande, Tobias Landmann, Hippolyte Affognon, Clas Ahlm, Magnus Evander
Distribution And Abundance Of Key Vectors Of Rift Valley Fever And Other Arboviruses In Two Ecologically Distinct Counties In Kenya, Rosemary Sang, Samwel Arum, Edith Chepkorir, Gladys Mosomtai, Caroline Tigoi, Faith Sigei, Olivia Wesula Lwande, Tobias Landmann, Hippolyte Affognon, Clas Ahlm, Magnus Evander
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Background: Rift Valley fever (RVF) is a mosquito-borne viral zoonosis of ruminants and humans that causes outbreaks in Africa and the Arabian Peninsula with significant public health and economic consequences. Humans become infected through mosquito bites and contact with infected livestock. The virus is maintained between outbreaks through vertically infected eggs of the primary vectors of Aedes species which emerge following rains with extensive flooding. Infected female mosquitoes initiate transmission among nearby animals, which amplifies virus, thereby infecting more mosquitoes and moving the virus beyond the initial point of emergence. With each successive outbreak, RVF has been found to expand …
The One Health Approach To Identify Knowledge, Attitudes And Practices That Affect Community Involvement In The Control Of Rift Valley Fever Outbreaks, Osama Ahmed Hassan, Hippolyte Affognon, Joacim Rocklöv, Peter Mburu, Rosemary Sang, Clas Ahlm, Magnus Evander
The One Health Approach To Identify Knowledge, Attitudes And Practices That Affect Community Involvement In The Control Of Rift Valley Fever Outbreaks, Osama Ahmed Hassan, Hippolyte Affognon, Joacim Rocklöv, Peter Mburu, Rosemary Sang, Clas Ahlm, Magnus Evander
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Rift Valley fever (RVF) is a viral mosquito-borne disease with the potential for global expansion, causes hemorrhagic fever, and has a high case fatality rate in young animals and in humans. Using a cross-sectional community-based study design, we investigated the knowledge, attitudes and practices of people living in small village in Sudan with respect to RVF outbreaks. A special One Health questionnaire was developed to compile data from 235 heads of household concerning their knowledge, attitudes, and practices with regard to controlling RVF. Although the 2007 RVF outbreak in Sudan had negatively affected the participants’ food availability and livestock income, …
Predicting Rift Valley Fever Inter-Epidemic Activities And Outbreak Patterns: Insights From A Stochastic Host-Vector Model, Sansao A. Pedro, Shirley Abelman, Henri E.Z. Tonnang
Predicting Rift Valley Fever Inter-Epidemic Activities And Outbreak Patterns: Insights From A Stochastic Host-Vector Model, Sansao A. Pedro, Shirley Abelman, Henri E.Z. Tonnang
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Rift Valley fever (RVF) outbreaks are recurrent, occurring at irregular intervals of up to 15 years at least in East Africa. Between outbreaks disease inter-epidemic activities exist and occur at low levels and are maintained by female Aedes mcintoshi mosquitoes which transmit the virus to their eggs leading to disease persistence during unfavourable seasons. Here we formulate and analyse a full stochastic host-vector model with two routes of transmission: vertical and horizontal. By applying branching process theory we establish novel relationships between the basic reproduction number, R0, vertical transmission and the invasion and extinction probabilities. Optimum climatic conditions and presence …
Molecular Identification Of Different Trypanosome Species And Subspecies In Tsetse Flies Of Northern Nigeria, Clement Isaac, Marc Ciosi, Alana Hamilton, Kathleen Maria Scullion, Peter Dede, Igho Benjamin Igbinosa, Oyebiguwa Patrick Goddey Nmorsi, Dan Masiga, C. Michael R. Turner
Molecular Identification Of Different Trypanosome Species And Subspecies In Tsetse Flies Of Northern Nigeria, Clement Isaac, Marc Ciosi, Alana Hamilton, Kathleen Maria Scullion, Peter Dede, Igho Benjamin Igbinosa, Oyebiguwa Patrick Goddey Nmorsi, Dan Masiga, C. Michael R. Turner
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Background: Animal African Trypanosomiasis (AAT) is caused by several species of trypanosomes including Trypanosoma congolense, T. vivax, T. godfreyi, T. simiae and T. brucei. Two of the subspecies of T. brucei also cause Human African Trypanosomiasis. Although some of them can be mechanically transmitted by biting flies; these trypanosomes are all transmitted by tsetse flies which are the cyclical vectors of Trypanosoma congolense, T. godfreyi, T. simiae and T. brucei. We present here the first report assessing the prevalence of trypanosomes in tsetse flies in Nigeria using molecular tools. Methods: 488 tsetse flies of three species, Glossina palpalis palpalis, G. …
Uncertainty And Sensitivity Analysis Of A Rift Valley Fever Model, S. A. Pedro, H. E.Z. Tonnang, S. Abelman
Uncertainty And Sensitivity Analysis Of A Rift Valley Fever Model, S. A. Pedro, H. E.Z. Tonnang, S. Abelman
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Rift Valley fever (RVF) is a vector-borne viral disease with pronounced health and economic impacts on domestic animals and humans in much of sub-Saharan Africa. Using techniques of uncertainty and sensitivity analysis (both local derivatives and sampling-based methods) of a mathematical model for RVF transmission in livestock by two population of mosquitoes (Aedes and Culex). We systematically investigate the relative importance of each model parameter for both disease epidemic and endemic activities. The relationship between vertical transmission and basic reproduction number reveals that during epidemic activities vertical transmission accelerates the course of the outbreak as it increases the size of …
Plant Resting Site Preferences And Parity Rates Among The Vectors Of Rift Valley Fever In Northeastern Kenya, Samwel O. Arum, Christopher W. Weldon, Benedict Orindi, Caroline Tigoi, Francis Musili, Tobias Landmann, David P. Tchouassi, Hippolyte D. Affognon, Rosemary Sang
Plant Resting Site Preferences And Parity Rates Among The Vectors Of Rift Valley Fever In Northeastern Kenya, Samwel O. Arum, Christopher W. Weldon, Benedict Orindi, Caroline Tigoi, Francis Musili, Tobias Landmann, David P. Tchouassi, Hippolyte D. Affognon, Rosemary Sang
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Background: Mosquito lifespan can influence the circulation of disease causing pathogens because it affects the time available for infection and transmission. The life-cycle of mosquitoes is determined by intrinsic and environmental factors, which can include the availability of hosts and suitable resting environments that shelter mosquitoes from extreme temperature and desiccating conditions. This study determined the parity rates (an indirect measure of survival) and plant resting preference of vectors of Rift Valley fever (RVF) in northeastern Kenya. Methods: Resting mosquitoes were trapped during the rainy and the dry season using a Prokopack aspirator from vegetation, whereas general adult populations were …
Mosquito Host Choices On Livestock Amplifiers Of Rift Valley Fever Virus In Kenya, David P. Tchouassi, Robinson O.K. Okiro, Rosemary Sang, Lee W. Cohnstaedt, David Scott Mcvey, Baldwyn Torto
Mosquito Host Choices On Livestock Amplifiers Of Rift Valley Fever Virus In Kenya, David P. Tchouassi, Robinson O.K. Okiro, Rosemary Sang, Lee W. Cohnstaedt, David Scott Mcvey, Baldwyn Torto
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Background: Animal hosts may vary in their attraction and acceptability as components of the host location process for assessing preference, and biting rates of vectors and risk of exposure to pathogens. However, these parameters remain poorly understood for mosquito vectors of the Rift Valley fever (RVF), an arboviral disease, and for a community of mosquitoes. Methods: Using three known livestock amplifiers of RVF virus including sheep, goat and cattle as bait in enclosure traps, we investigated the host-feeding patterns for a community of mosquitoes in Naivasha, an endemic area of Rift Valley fever (RVF), in a longitudinal study for six …
Linalool Oxide: Generalist Plant Based Lure For Mosquito Disease Vectors, Vincent O. Nyasembe, David P. Tchouassi, Charles M. Mbogo, Catherine L. Sole, Christian Pirk, Baldwyn Torto
Linalool Oxide: Generalist Plant Based Lure For Mosquito Disease Vectors, Vincent O. Nyasembe, David P. Tchouassi, Charles M. Mbogo, Catherine L. Sole, Christian Pirk, Baldwyn Torto
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Background: Lack of effective vaccines and therapeutics for important arboviral diseases such as Rift Valley fever (RVF) and dengue, necessitates continuous monitoring of vector populations for infections in them. Plant-based lures as surveillance tools has the potential of targeting mosquitoes of both sexes and females of varied physiological states; yet such lures are lacking for vectors of these diseases. Here, we present evidence of the effectiveness of linalool oxide (LO), a single plant-based lure previously developed for malaria vectors in trapping RVF vectors, Aedes mcintoshi and Aedes ochraceus, and dengue vector, Aedes aegypti. Methods: For RVF vectors, we used CDC …
Distribution And Diversity Of The Vectors Of Rift Valley Fever Along The Livestock Movement Routes In The Northeastern And Coastal Regions Of Kenya, Samwel O. Arum, Christopher W. Weldon, Benedict Orindi, Tobias Landmann, David P. Tchouassi, Hippolyte D. Affognon, Rosemary Sang
Distribution And Diversity Of The Vectors Of Rift Valley Fever Along The Livestock Movement Routes In The Northeastern And Coastal Regions Of Kenya, Samwel O. Arum, Christopher W. Weldon, Benedict Orindi, Tobias Landmann, David P. Tchouassi, Hippolyte D. Affognon, Rosemary Sang
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Background: Knowledge of vector ecology is important in understanding the transmission dynamics of vector borne disease. In this study, we determined the distribution and diversity of mosquitoes along the major nomadic livestock movement routes (LMR) in the traditional pastoral ecozone of northeastern Kenya. We focused on the vectors of Rift Valley fever virus (RVFv) with the aim of understanding their ecology and how they can potentially influence the circulation of RVFv. Methods: Mosquito surveys were conducted during the short and long rainy seasons from November 2012 to August 2014 using CO2-baited CDC light traps at seven sites selected for their …
Population Genetics Of Two Key Mosquito Vectors Of Rift Valley Fever Virus Reveals New Insights Into The Changing Disease Outbreak Patterns In Kenya, David P. Tchouassi, Armanda D.S. Bastos, Catherine L. Sole, Mawlouth Diallo, Joel Lutomiah, James Mutisya, Francis Mulwa, Christian Borgemeister, Rosemary Sang, Baldwyn Torto
Population Genetics Of Two Key Mosquito Vectors Of Rift Valley Fever Virus Reveals New Insights Into The Changing Disease Outbreak Patterns In Kenya, David P. Tchouassi, Armanda D.S. Bastos, Catherine L. Sole, Mawlouth Diallo, Joel Lutomiah, James Mutisya, Francis Mulwa, Christian Borgemeister, Rosemary Sang, Baldwyn Torto
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Rift Valley fever (RVF) outbreaks in Kenya have increased in frequency and range to include northeastern Kenya where viruses are increasingly being isolated from known (Aedes mcintoshi) and newly-associated (Ae. ochraceus) vectors. The factors contributing to these changing outbreak patterns are unclear and the population genetic structure of key vectors and/or specific virus-vector associations, in particular, are under-studied. By conducting mitochondrial and nuclear DNA analyses on >220 Kenyan specimens of Ae. mcintoshi and Ae. ochraceus, we uncovered high levels of vector complexity which may partly explain the disease outbreak pattern. Results indicate that Ae. mcintoshi consists of a species complex …
Stability, Bifurcation And Chaos Analysis Of Vector-Borne Disease Model With Application To Rift Valley Fever, Sansao A. Pedro, Shirley Abelman, Frank T. Ndjomatchoua, Rosemary Sang, Henri E.Z. Tonnang
Stability, Bifurcation And Chaos Analysis Of Vector-Borne Disease Model With Application To Rift Valley Fever, Sansao A. Pedro, Shirley Abelman, Frank T. Ndjomatchoua, Rosemary Sang, Henri E.Z. Tonnang
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This paper investigates a RVF epidemic model by qualitative analysis and numerical simulations. Qualitative analysis have been used to explore the stability dynamics of the equilibrium points while visualization techniques such as bifurcation diagrams, Poincaré maps, maxima return maps and largest Lyapunov exponents are numerically computed to confirm further complexity of these dynamics induced by the seasonal forcing on the mosquitoes oviposition rates. The obtained results show that ordinary differential equation models with external forcing can have rich dynamic behaviour, ranging from bifurcation to strange attractors which may explain the observed fluctuations found in RVF empiric outbreak data, as well …
Human African Trypanosomiasis Research Gets A Boost: Unraveling The Tsetse Genome, Serap Aksoy, Geoffrey Attardo, Matt Berriman, Alan Christoffels, Mike Lehane, Dan Masiga, Yeya Toure
Human African Trypanosomiasis Research Gets A Boost: Unraveling The Tsetse Genome, Serap Aksoy, Geoffrey Attardo, Matt Berriman, Alan Christoffels, Mike Lehane, Dan Masiga, Yeya Toure
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Human African trypanosomiasis (HAT), also known as sleeping sickness, is a neglected disease that impacts 70 million people distributed over 1.55 million km2 in sub-Saharan Africa [1]. Trypanosoma brucei gambiense accounts for almost 90% of the infections in central and western Africa, the remaining infections being from T. b. rhodesiense in eastern Africa [1]. Furthermore, the animal diseases caused by related parasites inflict major economic losses to countries already strained [2]. The parasites are transmitted to the mammalian hosts through the bite of an infected tsetse fly.
Comparative Diagnostic And Analytical Performance Of Pcr And Lamp-Based Trypanosome Detection Methods Estimated Using Pooled Whole Tsetse Flies And Midguts, Imna I. Malele, Johnson O. Ouma, John C.K. Enyaru, Enock Matovu, Vincent Alibu, Joanna E. Auma, Samuel G. Onyoyo, Rosemary Bateta, Robert E. Changasi, Phoebe W. Mukiria, Kariuki Ndung'u, Purity K. Gitonga, Lilian M. Mwaniki, Hamisi S. Nyingilili, Eugene A. Lyaruu, Lupakisyo A. Kapange, Peter Kuria Kamau, Daniel K. Masiga
Comparative Diagnostic And Analytical Performance Of Pcr And Lamp-Based Trypanosome Detection Methods Estimated Using Pooled Whole Tsetse Flies And Midguts, Imna I. Malele, Johnson O. Ouma, John C.K. Enyaru, Enock Matovu, Vincent Alibu, Joanna E. Auma, Samuel G. Onyoyo, Rosemary Bateta, Robert E. Changasi, Phoebe W. Mukiria, Kariuki Ndung'u, Purity K. Gitonga, Lilian M. Mwaniki, Hamisi S. Nyingilili, Eugene A. Lyaruu, Lupakisyo A. Kapange, Peter Kuria Kamau, Daniel K. Masiga
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Detection of trypanosomes that cause disease in human beings and livestock within their tsetse fly hosts is an essential component of vector and disease control programmes. Several molecular-based diagnostic tests have been developed for this purpose. Many of these tests, while sensitive, require analysis of trypanosome DNA extracted from single flies, or from pooled tsetse fly heads and amplified trypanosome DNA. In this study, we evaluated the relative analytical and diagnostic sensitivities of two PCR-based tests (ITS and TBR) and a Trypanozoon specific LAMP assay using pooled whole tsetse flies and midguts spiked with serially diluted procyclics of a laboratory …
Parasitological Prevalence Of Bovine Trypanosomosis In Kubo Division Of Kwale County Of Coastal: Baseline Survey, N. Mbahin, H. Affognon, J. Andoke, M. Tiberius, D. Mbuvi, J. Otieno, P. Muasa, R. K. Saini
Parasitological Prevalence Of Bovine Trypanosomosis In Kubo Division Of Kwale County Of Coastal: Baseline Survey, N. Mbahin, H. Affognon, J. Andoke, M. Tiberius, D. Mbuvi, J. Otieno, P. Muasa, R. K. Saini
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Prior to field trials of large scale tsetse repellent technology validation in July 2011, a cross-sectional survey of bovine trypanosomosis and its vectors was carried out to know the disease level in Kwale County of Coastal Kenya. A total of 584 adult cattle were examined at ten different Locations. The trypanosome prevalence in cattle with regard to age, sex, location and apparent tsetse density was investigated. The overall trypanosome prevalence in cattle in Kubo Division of Kwale County was 33.9%. Two types of infections were recorded in various parts of the Division in the following proportions: T. congolense 61.1%, T. …
Common Host-Derived Chemicals Increase Catches Of Disease-Transmitting Mosquitoes And Can Improve Early Warning Systems For Rift Valley Fever Virus, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto
Common Host-Derived Chemicals Increase Catches Of Disease-Transmitting Mosquitoes And Can Improve Early Warning Systems For Rift Valley Fever Virus, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto
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Rift Valley fever (RVF), a mosquito-borne zoonosis, is a major public health and veterinary problem in sub-Saharan Africa. Surveillance to monitor mosquito populations during the inter-epidemic period (IEP) and viral activity in these vectors is critical to informing public health decisions for early warning and control of the disease. Using a combination of field bioassays, electrophysiological and chemical analyses we demonstrated that skin-derived aldehydes (heptanal, octanal, nonanal, decanal) common to RVF virus (RVFV) hosts including sheep, cow, donkey, goat and human serve as potent attractants for RVFV mosquito vectors. Furthermore, a blend formulated from the four aldehydes and combined with …
Sheep Skin Odor Improves Trap Captures Of Mosquito Vectors Of Rift Valley Fever, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Klaus Mithoefer, Baldwyn Torto
Sheep Skin Odor Improves Trap Captures Of Mosquito Vectors Of Rift Valley Fever, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Klaus Mithoefer, Baldwyn Torto
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In recent years, the East African region has seen an increase in arboviral diseases transmitted by blood-feeding arthropods. Effective surveillance to monitor and reduce incidence of these infections requires the use of appropriate vector sampling tools. Here, trapped skin volatiles on fur from sheep, a known preferred host of mosquito vectors of Rift Valley fever virus (RVFV), were used with a standard CDC light trap to improve catches of mosquito vectors. We tested the standard CDC light trap alone (L), and baited with (a) CO2 (LC), (b) animal volatiles (LF), and (c) CO2 plus animal volatiles (LCF) in two highly …
Viral Metagenomics Demonstrates That Domestic Pigs Are A Potential Reservoir For Ndumu Virus, Charles Masembe, George Michuki, Maria Onyango, Cecilia Rumberia, Martin Norling, Richard P. Bishop, Appolinaire Djikeng, Stephen J. Kemp, Alan Orth, Robert A. Skilton, Karl Ståhl, Anne Fischer
Viral Metagenomics Demonstrates That Domestic Pigs Are A Potential Reservoir For Ndumu Virus, Charles Masembe, George Michuki, Maria Onyango, Cecilia Rumberia, Martin Norling, Richard P. Bishop, Appolinaire Djikeng, Stephen J. Kemp, Alan Orth, Robert A. Skilton, Karl Ståhl, Anne Fischer
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Background: The rising demand for pork has resulted in a massive expansion of pig production in Uganda. This has resulted in increased contact between humans and pigs. Pigs can act as reservoirs for emerging infectious diseases. Therefore identification of potential zoonotic pathogens is important for public health surveillance. In this study, during a routine general surveillance for African swine fever, domestic pigs from Uganda were screened for the presence of RNA and DNA viruses using a high-throughput pyrosequencing method. Findings. Serum samples from 16 domestic pigs were collected from five regions in Uganda and pooled accordingly. Genomic DNA and RNA …
Trapping Of Rift Valley Fever (Rvf) Vectors Using Light Emitting Diode (Led) Cdc Traps In Two Arboviral Disease Hot Spots In Kenya, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Lee W. Cohnstaedt, Baldwyn Torto
Trapping Of Rift Valley Fever (Rvf) Vectors Using Light Emitting Diode (Led) Cdc Traps In Two Arboviral Disease Hot Spots In Kenya, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Lee W. Cohnstaedt, Baldwyn Torto
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Background: Mosquitoes response to artificial lights including color has been exploited in trap designs for improved sampling of mosquito vectors. Earlier studies suggest that mosquitoes are attracted to specific wavelengths of light and thus the need to refine techniques to increase mosquito captures following the development of super-bright light-emitting diodes (LEDs) which emit narrow wavelengths of light or very specific colors. Therefore, we investigated if LEDs can be effective substitutes for incandescent lamps used in CDC light traps for mosquito surveillance, and if so, determine the best color for attraction of important Rift Valley Fever (RFV) vectors. Methods. The efficiency …
The 2007 Rift Valley Fever Outbreak In Sudan, Osama Ahmed Hassan, Clas Ahlm, Rosemary Sang, Magnus Evander
The 2007 Rift Valley Fever Outbreak In Sudan, Osama Ahmed Hassan, Clas Ahlm, Rosemary Sang, Magnus Evander
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Rift Valley fever (RVF) is a neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health and economy. RVF is caused by RVF virus (RVFV) affecting humans and a wide range of animals. The virus is transmitted through bites from mosquitoes and exposure to viremic blood, body fluids, or tissues of infected animals. During 2007 a large RVF outbreak occurred in Sudan with a total of 747 confirmed human cases including 230 deaths (case fatality 30.8%); although it has been estimated 75,000 were infected. It was most severe in White Nile, El Gezira, and Sennar states near …
Chemical Ecology, Population Dynamics And Insecticide Susceptibility Of Lesser Mealworm Alphitobius Diaperinus (Panzer) (Coleoptera: Tenebrionidae), Narinderpal Singh
Chemical Ecology, Population Dynamics And Insecticide Susceptibility Of Lesser Mealworm Alphitobius Diaperinus (Panzer) (Coleoptera: Tenebrionidae), Narinderpal Singh
Graduate Theses and Dissertations
The lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), is a serious, cosmopolitan pest present in poultry production facilities, where it slows down weight gain in chicks, carries disease–causing organisms, and causes damage to poultry insulation. The first study estimated that the lesser mealworm densities in poultry litter applied to pastures were 3.5, 2.2 and 0.4 million larvae, adults and pupae, respectively, per hectare in Savoy, Arkansas. The repercussions of these adult beetles are that they often disperse to and reinfest poultry houses with the potential to vector disease to poultry, and disperse to invade human dwellings resulting in litigation. The …
Landmarks In The Evolution Of Technologies For Identifying Trypanosomes In Tsetse Flies, John C. Enyaru, Johnson O. Ouma, Imna I. Malele, Enock Matovu, Daniel K. Masiga
Landmarks In The Evolution Of Technologies For Identifying Trypanosomes In Tsetse Flies, John C. Enyaru, Johnson O. Ouma, Imna I. Malele, Enock Matovu, Daniel K. Masiga
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Understanding what the trypanosome pathogens are, their vectors and mode of transmission underpin efforts to control the disease they cause in both humans and livestock. The risk of transmission is estimated by determining what proportion of the vector population is carrying the infectious pathogens. This risk also depends on the infectivity of the trypanosomes to humans and livestock. Most livestock pathogens are not infective to humans, whereas the two sub-species that infect humans also infect livestock. As with other infectious diseases, we can therefore trace the foundation of many continuing disease control programs for trypanosomiasis to the discovery of the …