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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Epidemiology and strain differentiation of Echinococcus granulosus in Kenya

MacPherson, Calum Norman Lindsay January 1981 (has links)
No description available.
2

The ecology of sandflies (Diptera: Psychodidae), vectors of cutaneous leishmaniasis, in the Andes of Western Venezuela

Valenta, David Thomas January 2000 (has links)
No description available.
3

Understanding Environmental and Anthropogenic Drivers of Lemur Health in Madagascar: The Importance of a One Health Perspective

Barrett, Meredith Ann January 2011 (has links)
<p>Anthropogenic effects on ecosystems have expanded in their scope and intensity, with significant consequences for global environmental, wildlife and human health. As human encroachment into wildlife habitat grows, habitat degradation and fragmentation intensify, leading to increased contact among wildlife, humans and domestic animals. Due to this increasing frequency of interaction, and the emergence of several high-profile diseases, global concern has grown over the risk of emerging infectious disease from zoonotic origins. </p><p>Due to Madagascar's rampant rate of human population growth and deforestation, its incredible species diversity, the widespread presence of domestic and invasive species, and its evolutionary isolation, it can be viewed as a high risk region for potential disease emergence. There is a need for assessment of the zoonotic and reverse zoonotic disease potential within this country. </p><p>To contribute to this assessment, consistent baseline health monitoring provides an effective tool for evaluating wildlife health and preparing for future disease occurrences. Limited, disconnected surveys of lemur health have occurred, yet there remained a need for more extensive, country-wide evaluations that also addresses invasive species, domestic animal and human health, as well shifting patterns of environmental and climatic change. </p><p>This research has investigated the connections among human, animal (both domestic and wildlife) and ecosystem health in Madagascar. I have examined current trends in anthropogenically-driven environmental change in Madagascar--including deforestation, illegal logging of precious hardwoods, mining, hunting, and agriculture--and evaluated how this change affects patterns of lemur, domestic animal and human health by evaluating a suite of health measures and parasite prevalence and richness. I have also examined how predicted global climate changes may influence the spatial patterns of lemur parasites and human infectious disease by assessing their shifts in distributions and geographic extent. </p><p>To assess the risk of disease transmission among lemur, domestic animal and human hosts, I have modeled the areas of geographic overlap among these parasites and their hosts and identified high-risk areas for disease emergence using geospatial analysis. This information can help to develop predictive statistical and spatial tools, which can inform both environmental management and public health planning. </p><p>Through this work, I have evaluated the severe loss of distribution that rosewood species have undergone, which highly qualifies them for international trade protection. We predicted areas of high risk for future logging, many of which occurred within protected areas in the biodiverse northeast. </p><p>Secondly, I have compiled the most comprehensive record of parasites of lemurs to date. Building upon the Prosimian Biomedical Survey Project data and the published literature, we have recorded 88 parasites that have been documented in lemurs. These are composed of helminths, bacteria, ectoparasites and protozoa. Of the 23 focal parasite species studied more in depth in this study, we noted high variability in prevalence measures for unique parasites at different sites. Parasite coinfection occurred quite commonly, with up to as many as 7 parasites concurrently. On average, lemur parasites tend to be less species-, genus-, or family-specific than other parasites across all primates. </p><p>Thirdly, I documented highly significant differences in health measures from two populations of Indri that exist under differing levels of anthropogenic pressure. Of note, the parasite richness, leukocyte count and differential, and nickel and cobalt levels were significantly higher in the more exposed population, while the total protein measures were significantly lower. These data suggest that the exposed population experiencing more anthropogenic pressure suffered from elevated health and nutritional stress. </p><p>Fourthly, I have documented strong correlations among environmental drivers (temperature, precipitation and landscape-scale features) and lemur parasite distributions. Striking shifts in their distributions are predicted to occur with projected climate change in Madagascar, including an expansion of helminth, virus and ectoparasite distributions, but a contraction of bacteria distributions due to warming and drying in the south. </p><p>Fifthly, I have examined 10 human and domestic animal parasites that hold great consequence for lemur, human and domestic animal health in Madagascar. I have similarly demonstrated strong correlations among environmental drivers (temperature, precipitation and landscape-scale features) and the distributions of these human parasites. Shifts in the distributions are also predicted to occur with projected climate change, including an expansion of helminth parasites, and a contraction of viruses and bacteria due to warming and drying in the south. I have identified areas of high risk for the transmission of parasites from human hosts to lemurs, as well as conversely from lemur hosts to humans. These risk indices will serve to highlight geographic areas at particular risk, and will also help to direct limited funds and staff to those areas most in need of attention. </p><p>Sixthly, I have demonstrated a need to train a growing cadre of One Health professionals from many different disciplines. I have offered several suggestions to integrate One Health training into graduate education, and have identified several geographic regions of potential to be a Center of One Health Excellence, of which the North Carolina Triangle area is one of great promise.</p> / Dissertation
4

Best practices for designing and planning events where human-animal interactions are encouraged, based on observations of risk behaviors and hand hygiene at such events

Erdozain, Gonzalo January 1900 (has links)
Master of Public Health / Department of Diagnostic Medicine/Pathobiology / Douglas Powell / Outbreaks of human illness have been linked to visiting settings with animal contact throughout developed countries. These outbreaks demonstrate that although contact with animals in public settings can provide educational and entertainment opportunities, the potential to spread disease exists if risk-reduction tools are not implemented, proper hygiene measures aren’t practiced, and precautions are not taken and reinforced. This thesis is divided into two parts. Part one is an observational study of hand hygiene tool availability and recommendations; frequency of risky behavior; and, handwashing attempts by visitors in Kansas and Missouri, U.S., petting zoos. Part two delineates best practices for organizing events where human-animal interactions are encouraged, in hopes it will lower the risk of zoonotic disease transmission. Handwashing signs and hand hygiene stations were available at the exit of animal-contact areas in 10/13 and 8/13 petting zoos respectively. Risky behaviors were observed being performed at all petting zoos by at least one visitor. Frequently observed behaviors were: children (10/13 petting zoos) and adults (9/13 petting zoos) touching hands to face within animal-contact areas; animals licking children’s and adults’ hands (7/13 and 4/13 petting zoos, respectively); and children and adults drinking within animal-contact areas (5/13 petting zoos each). Of 574 visitors observed for hand hygiene when exiting animal-contact areas, 37% (n=214) of individuals attempted some type of hand hygiene, with male adults, female adults, and children attempting at similar rates (32%, 40%, and 37% respectively). Visitors performed hand hygiene more often when a staff member was present within or at the exit to the animal-contact area (136/231, 59%) than when no staff member was present (78/343, 23%; P < 0.001, OR = 4.863, 95% CI = 3.380–6.998), and in petting zoos where animal contact occurred over a fence (188/460, 40.9%) as opposed to visitors entering an animals’ yard for contact (26/114, 22.8%; P < 0.001, OR = 2.339, 95% CI = 1.454–3.763). Inconsistencies existed in tool availability, signage, and supervision of animal- contact. Risk communication was poor, with few petting zoos outlining risks associated with animal-contact, or providing recommendations for precautions to be taken to reduce these risks. Recommendations made in the second part of this thesis were based on these observations, recent publications, and the suggestions of many health agencies. It focuses on what event planners can do to design and plan a safer event, and what staff working at the event should be aware of in order to inform visitors and lower the risk of zoonotic disease transmission. Part two discusses two primary tools to reduce risk of zoonotic disease transmission: sanitation and awareness of risk behaviors. Keeping facilities, animals, and visitors clean, and informing visitors of risky behaviors to avoid, while reinforcing positive messages within the animal- contact area, can lower the risk of zoonotic infection. Included with the second part, is a checklist (see appendix A) designed for visitors to assess whether an event that encourages human-animal interaction poses a high or low risk. By identifying possible risk factors, teachers and parents will be able to make an informed decision about the safety of the human-animal encounter.
5

The Socioeconomic and Ecological Drivers of Avian Influenza Risks in China and at the International Level

January 2018 (has links)
abstract: Avian influenzas are zoonoses, or pathogens borne by wildlife and livestock that can also infect people. In recent decades, and especially since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in 1996, these diseases have become a significant threat to animal and public health across the world. HPAI H5N1 has caused severe damage to poultry populations, killing, or prompting the culling of, millions of birds in Asia, Africa, and Europe. It has also infected hundreds of people, with a mortality rate of approximately 50%. This dissertation focuses on the ecological and socioeconomic drivers of avian influenza risk, particularly in China, the most populous country to be infected. Among the most significant ecological risk factors are landscapes that serve as “mixing zones” for wild waterfowl and poultry, such as rice paddy, and nearby lakes and wetlands that are important breeding and wintering habitats for wild birds. Poultry outbreaks often involve cross infections between wild and domesticated birds. At the international level, trade in live poultry can spread the disease, especially if the imports are from countries not party to trade agreements with well-developed biosecurity standards. However, these risks can be mitigated in a number of ways. Protected habitats, such as Ramsar wetlands, can segregate wild bird and poultry populations, thereby lowering the chance of interspecies transmission. The industrialization of poultry production, while not without ethical and public health problems, can also be risk-reducing by causing wild-domestic segregation and allowing for the more efficient application of surveillance, vaccination, and other biosecurity measures. Disease surveillance is effective at preventing the spread of avian influenza, including across international borders. Economic modernization in general, as reflected in rising per-capita GDP, appears to mitigate avian influenza risks at both the national and sub-national levels. Poultry vaccination has been effective in many cases, but is an incomplete solution because of the practical difficulties of sustained and widespread implementation. The other popular approach to avian influenza control is culling, which can be highly expensive and raise ethical concerns about large-scale animal slaughter. Therefore, it is more economically efficient, and may even be more ethical, to target the socio-ecological drivers of avian influenza risks, including by implementing the policies discussed here. / Dissertation/Thesis / Doctoral Dissertation Biology 2018
6

A Pilot Study of Potential Public Health Hazards in the Animal Hoarding Environment

Mielke, Sarah Rebecca 28 May 2015 (has links)
No description available.
7

A comparison study of gravid and under house CO2 mosquito traps in Harris County, Texas

White, Stephanie Lyn 10 October 2008 (has links)
Harris County Mosquito Control Division (HCMCD) is responsible for surveillance of mosquito species that are vectors of St. Louis Encephalitis (SLE) virus and West Nile Virus (WNV) within Harris County, Texas, including the Houston metroplex. The metroplex area has some unique attributes and a vast variety of environmental habitats that are attractive to vectors of arboviruses and for the transmission of arboviruses to the human population. Data describing the efficacy of Gravid (GV) and Underhouse (UH) CO2 traps were analyzed to determine if there is a significant difference between these two trap types with respect to the number of mosquitoes and the variety of mosquito species caught. This study was conducted during the off-peak HCMCD trapping season, to gain information in preparation for a yearround trapping program utilizing Underhouse CO2 traps for WNV and SLE virus surveillance. Adjusting for the week of collection, results suggest that Gravid traps caught significantly (P = 0.009) more mosquitoes (mean = 23.134 per trap) in the study area than Underhouse traps (mean = 3.616 per trap), and that Underhouse Traps caught a larger variety of mosquito species (n = 13) than Gravid Traps (n = 11), out of 15 total different species caught. Gravid and Underhouse traps caught 9 out of 15 of the same mosquito species during the study period. Culex quinquefasciatus mosquito catches in Gravid traps and temperature were strongly correlated (Spearman's Correlation Coefficient = 0.707, P = 0.005). Geographic Information System spatial analysis indicated clustering of Culex quinquefasciatus mosquito catches in both Gravid traps, week 9 and 21 (Moran's I = 0.69, P = 0.040 and 0.74, P = 0.021, respectfully ) and Underhouse traps, week 13 and 19 (Moran's I = 0.92, P = 0.002, and 0.89, P = 0.011, respectfully). It is recommended that Harris County Mosquito Control Division continue to utilize gravid traps as a primary method of surveillance. Gravid traps (16,194) caught 85% more mosquitoes than Underhouse traps (2,531) over the fourteen week study period. Their overall success far outweighs the additional materials or labor required for their use in a successful surveillance program.
8

Modeling the Role of Land-Use Change on the Spread of Infectious Disease

January 2020 (has links)
abstract: Land-use change has arguably been the largest contributor to the emergence of novel zoonotic diseases within the past century. However, the relationship between patterns of land-use change and the resulting landscape configuration on disease spread is poorly understood as current cross-species disease transmission models have not adequately incorporated spatial features of habitats. Furthermore, mathematical-epidemiological studies have not considered the role that land-use change plays in disease transmission throughout an ecosystem. This dissertation models how a landscape's configuration, examining the amount and shape of habitat overlap, contributes to cross-species disease transmission to determine the role that land-use change has on the spread of infectious diseases. To approach this, an epidemiological model of transmission between a domesticated and a wild species is constructed. Each species is homogeneously mixed in its respective habitat and heterogeneously mixed in the habitat overlap, where cross-species transmission occurs. Habitat overlap is modeled using landscape ecology metrics. This general framework is then applied to brucellosis transmission between elk and cattle in the Greater Yellowstone Ecosystem. The application of the general framework allows for the exploration of how land-use change has contributed to brucellosis prevalence in these two species, and how land management can be utilized to control disease transmission. This model is then extended to include a third species, bison, in order to provide insight to the indirect consequences of disease transmission for a species that is situated on land that has not been converted. The results of this study can ultimately help stakeholders develop policy for controlling brucellosis transmission between livestock, elk, and bison, and in turn, could lead to less disease prevalence, reduce associated costs, and assist in population management. This research contributes novelty by combining landscape ecology metrics with theoretical epidemiological models to understand how the shape, size, and distribution of habitat fragments on a landscape affect cross-species disease transmission. The general framework demonstrates how habitat edge in single patch impacts cross-species disease transmission. The application to brucellosis transmission in the Greater Yellowstone Ecosystem between elk, cattle, and bison is original research that enhances understanding of how land conversion is associated with enzootic disease spread. / Dissertation/Thesis / Doctoral Dissertation Applied Mathematics for the Life and Social Sciences 2020
9

Knowledge and practice of live bird sellers on health risks and preventive measure of Avian Influenza in an urban community of Lagos state, Nigeria

Chinyere Charity Ilonze January 2010 (has links)
<p>Avian Influenza (AI) is a contagious viral zoonotic disease with great public health implications and negative socioeconomic impact (WHO, 2006a). The highly pathogenic avian influenza (HPAI) infection is transmitted from birds to man mostly through contact with contaminated poultry and objects (INFOSAN, 2005), hence people who come in contact with birds such as live bird sellers (LBS) are the more vulnerable population (WHO, 2006a). Inadequate knowledge of AI health risks and poor practice of AI preventive measures amongst LBS increases the risk of spread of the infection in both humans and animals.The aim of this study was to describe and quantify the knowledge and practice of LBS with regards to avian influenza health risks and preventive activities in Agege, an urban area in Lagos State, Nigeria.</p>
10

Knowledge and practice of live bird sellers on health risks and preventive measure of Avian Influenza in an urban community of Lagos state, Nigeria

Chinyere Charity Ilonze January 2010 (has links)
<p>Avian Influenza (AI) is a contagious viral zoonotic disease with great public health implications and negative socioeconomic impact (WHO, 2006a). The highly pathogenic avian influenza (HPAI) infection is transmitted from birds to man mostly through contact with contaminated poultry and objects (INFOSAN, 2005), hence people who come in contact with birds such as live bird sellers (LBS) are the more vulnerable population (WHO, 2006a). Inadequate knowledge of AI health risks and poor practice of AI preventive measures amongst LBS increases the risk of spread of the infection in both humans and animals.The aim of this study was to describe and quantify the knowledge and practice of LBS with regards to avian influenza health risks and preventive activities in Agege, an urban area in Lagos State, Nigeria.</p>

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