Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Veterinária, 2014. / Submitted by Raquel Viana (raquelviana@bce.unb.br) on 2014-10-15T19:35:53Z No. of bitstreams: 1 2014_GustavoPereiraMartins.pdf: 887956 bytes, checksum: 3a35a77e4ed4984bbc154ab9a2cde15d (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2014-10-21T14:57:53Z (GMT) No. of bitstreams: 1 2014_GustavoPereiraMartins.pdf: 887956 bytes, checksum: 3a35a77e4ed4984bbc154ab9a2cde15d (MD5) / Made available in DSpace on 2014-10-21T14:57:53Z (GMT). No. of bitstreams: 1 2014_GustavoPereiraMartins.pdf: 887956 bytes, checksum: 3a35a77e4ed4984bbc154ab9a2cde15d (MD5) / A febre maculosa brasileira (FMB) é uma zoonose causada pela bactéria Rickettsia rickettsii e transmitida a humanos por carrapatos. Procurou-se detectar a presença do principal agente etiológico da FMB circulando em equinos apreendidos no Distrito Federal, Brasil. Durante um ano foram coletadas amostras de sangue e ectoparasitos de 122 equinos. Após teste por reação de imunofluorescência indireta (RIFI), para anticorpos IgG anti R. rickettsii 21 amostras foram positivas em titulações variáveis de 1:64 a 1:512. Dos 618 carrapatos coletados, 449 pertenciam ao gênero Anocentor, 113 ao Boophilus e 36 do gênero Amblyomma. Como conclusão foi possível identificar a circulação de Rickettsia em equinos no DF, Brasil. ______________________________________________________________________________________ ABSTRACT / The Brazilian spotted fever (BSF) is a zoonosis caused by the bacteria Rickettsia rickettsii and transmitted to humans by ticks. In this study we tried to detect the BSF ethiological agent in horses apprehended by animal control in Distrito Federal, Brazil. Over one year the blood and ectoparasites were sampled on 122 horses. The samples were tested by indirect imunnofluorescence antibody assay (IFA) for R. rickettsii anti-IgG antibody, 21 samples were positive for titer ranging from 1:64 to 1:512. Among the 618 ticks collected, 449 belonged to the Anocentor genus, 113 to Boophilus and 36 were Amblyomma. The bacteria were detected in horses in Distrito Federal.

Foi efetuado um inquérito epidemiológico do potencial zoonótico da população canina da Estância Turística de Ibiúna, SP. As zoonoses investigadas foram: leishmaniose, leptospirose, brucelose (B.canis), toxoplasmose, neosporose e doença de Chagas. As características analisadas foram: ocorrência, prevalência, distribuição espacial e fatores de risco. As colheitas de sangue foram efetuadas no período de 2007 a 2008 de uma amostra representativa (n=570), aleatória e estratificada da população canina do município. Por ocasião das colheitas de sangue os proprietários dos animais responderam a um questionário elaborado para permitir o cálculo dos fatores de risco. Os 48 bairros do município foram agrupados em quatro regiões caracterizadas por: região 1 composta por áreas mistas de urbanização recente, sem infra-estrutura adequada e com deficiência de serviços e áreas rurais formadas por pequenas propriedades agrícolas; região 2 de característica predominantemente rural formada por pequenas propriedades agrícolas e sítios circundados por áreas de mata; região 3 formada por área urbanizada que dispõe infra-estrutura organizada; região 4 também apresenta o predomínio de pequenas propriedades rurais para plantio e lazer, circundadas por áreas de mata. Não foram examinados animais do Parque Estadual de Jurupará. A leptospirose foi investigada pela técnica de soroaglutinação microscópica, com uma coleção de 24 sorovariedades de leptospiras, a leishmaniose por uma reação imunoenzimática, a brucelose (B.canis) por cultivo microbiológico e toxoplasmose, neosporose e doença de Chagas por imunofluorescência indireta. Os resultados obtidos foram analisados pelo teste de qui quadrado ou exato de Fisher, quando indicado, o nível de significância adotado foi o de 0,05. Foram encontrados animais reatores para as seis zoonoses estudadas, com taxas de prevalência de: 1,1%, 2,3%, 6,1%, 7,0%, 32,8% e 55,1%, respectivamente para: brucelose por (B.canis), leishmaniose, doença de Chagas, neosporose, leptospirose e toxoplasmose. As variantes sorológicas de leptospiras predominantes em ordem decrescente de ocorrência foram: Pyrogenes, Autumnalis e Canicola. As variáveis sexo masculino, idade adulta, presença de roedores, permanência nas vias públicas, ingestão de carne crua e atividade sexual foram caracterizadas como fatores de risco para leptospirose e toxoplasmose; a permanência nas vias públicas foi caracterizada como fator de risco para brucelose; sexo masculino, idade adulta e atividade sexual foram caracterizados como fatores de risco para neosporose; contato com carrapatos foi caracterizado como fator de risco para doença de Chagas. As prevalências de leishmaniose, leptospirose, brucelose, toxoplasmose e neosporose não diferiram segundo área rural ou urbana bem como nas quatro regiões em que o município foi dividido. A prevalência da doença de Chagas foi idêntica em área rural ou urbana, mas o valor observado na região 4 (bairros: Campo Verde, Rio Una de Cima, Ressaca e Paruru) foi superior ao encontrado nas demais. / A seroepidemiologic survey was performed aiming to evaluate the zoonotic potential of the canine population of the tourist city of Ibiúna, São Paulo, Southeastern Brazil. The frequency of the occurrence, spatial distribution and associated risk factors of leishmaniasis, leptospirosis, brucellosis (Brucella canis), toxoplasmosis, neosporosis and Chagas' disease were investigated during the period of 2007 to 2008, in 570 blood samples gathered randomly from a stratified canine population, divided in 48 districts of the municipality which were grouped into four main regions characterized as: region 1 consists of mixed areas of recent urbanization without adequate infrastructure and services and rural areas formed by small properties; region 2 predominantly agricultural characteristic with small rural farms and properties surrounded by forest areas; region 3 formed by urbanized area with organized infrastructure, region 4 also presents the predominance of small country properties for planting and leisure, surrounded by forest areas. The animals of the State Park of Jurupará were not examined. During the blood collection, a questionnaire was applied to the owners of animals, in order to afford the epidemiological profile of the population and to carry out statistical analysis of risk factors. Leptospirosis was investigated by microscopic serum agglutination technique using a collection of 24 leptospira serovars, for leishmaniasis it was employed the ELISA technique and for brucellosis, by microbiological cultivation of B. canis and the toxoplasmosis, neosporosis and Chagas' disease, by using the indirect immunofluorescence techniques. The results were analyzed by the qui square (X2) test or by the Fisher's exact test, when indicated, using the significance level of α = 0.05. Positive reactant animals were found for leishmaniasis, leptospirosis, brucellosis, toxoplasmosis, neosporosis and Chagas' disease, with positive rates respectively of 2.3%, 32.8%, 1.05%, 55.1%, 7.0% and 6.1%. The most frequent serovars of leptospires, in decreasing order of occurrence were: Pyrogenes, Autumnalis and Canicola. Variables like "Male sex", "age", "presence of rodents", "permanence in streets", "ingestion of raw meat" and "sexual activity" were characterized as risk factors for the occurrence of leptospirosis and toxoplasmosis. Permanence in streets" was characterized as a risk factor for the occurrence of brucellosis. "Male sex", "age" and "sexual activity" were characterized as risk factors for the occurrence of neosporosis. The "contact with ticks" was characterized as a risk factor for the occurrence of Chagas' disease. The frequencies of occurrence of leishmaniasis, leptospirosis, brucellosis, toxoplasmosis and neosporosis were similar in rural and urban areas as well as in the four regions studied in Ibiúna. The positive rates of Chagas' disease was similar both in rural and urban areas, however, frequencies of Chagas' disease was significantly higher in region 4.

Made available in DSpace on 2014-06-12T16:29:33Z (GMT). No. of bitstreams: 2 arquivo4897_1.pdf: 8357327 bytes, checksum: 46d7207290a153cad6a38d771aae9c1c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2004 / A Cartografia tem sido utilizada pela saúde pública desde 1854 com os estudos do Dr. John Snow, que a partir de dados descritivos dos óbitos e a base espacial do centro de Londres, conseguiu controlar o problema da epidemia da cólera. A pesquisa aqui desenvolvida teve como objetivos gerar um aplicativo para monitoramento epidemiológico utilizando SIG - Sistemas de Geoinformação, fornecer subsídios às secretarias de saúde e avaliar a aplicação de técnicas de análise espacial. Para tanto, foram utilizados conceitos de Cartografia, com ênfase em SIG, e de epidemiologia com o estudo da zoonose Leishmaniose visceral - Calazar, tendo como área piloto ZEIS Zonas Especiais de Interesse Social em Jaboatão dos Guararapes - PE. Como resultado, foi desenvolvido um sistema aplicativo em SIG utilizando a plataforma SPRING, de consulta pela internet, tendo sido aplicada à metodologia de Modelagem de Dados Espaciais

O ProMAC surgiu dentro da USP como resposta à demanda da comunidade, de abordar alguns problemas ambientais, inclusive a presença de cães errantes no campus. O presente trabalho teve como objetivo atender este programa no tocante à avaliação da dinâmica e da saúde da população de cães mantidos soltos na CUASO e dos cães recolhidos ao ATA. Utilizando a técnica de captura e recaptura fotográfica, a população de cães foi estimada em nove oportunidades ao longo de dois anos. No segundo ano, os cães dóceis foram individualmente identificados e, em quatro oportunidades, tiveram amostras biológicas coletadas (sangue, fezes e ectoparasitos). Os cães alojados no ATA foram identificados e as amostras coletadas em um único esforço contínuo ao longo de três meses. A estimativa da população errante variou entre 14 e 55 cães, com tendencia de queda não significativa ao longo do tempo. A população foi, em sua maioria composta de indivíduos machos (58,4%), adultos (77,8%) e dóceis (55,7%). A população errante apresentou alterações nos parâmetros hematológicos ao longo do ano, compatíveis com infecção subclínica, possivelmente causada por Hepatozoon canis, que teve aumento significativo de sua prevalência. Todos os cães foram negativos para Leishmania sp., Ricketsia sp., Erlichia sp. Não houve diferença significativa tanto para a SAM (Leptospira sp.,entre 14 e 50% - CUASO e 52,4% - ATA) quanto para a eliminação de ovos de Ancylostoma sp. nas fezes (entre 21 e 55% - CUASO e 27% - ATA) entre os cães da CUASO e do ATA, sendo o risco de infecção na comunidade universitária considerado baixo. A análise ambiental permitiu estabelecer que a fonte principal de alimento dos cães é a mesma dos humanos, fornecida próximo aos pontos de venda de alimentos, o que se torna preocupante ao sabermos que mais da metade destes cães são positivos para Toxoplasma sp. (entre 54 e 60%), sendo indicadores do risco ao ser humano. Os cães da população aversiva apresentam sinais reprodutivos (8,7% das fêmeas ao ano), mas os filhotes não foram encontrados possivelmente devido à baixa sobrevivência. Os adultos, tanto da população dócil como da população aversiva possuiam boa condição corporal, baixa mortalidade, sendo que os dóceis deixaram o campus mais frequentemente devido à adoção. O conjunto dos dados indicaram que o status sanitário dos cães alojados no abrigo foi semelhante àquela dos cães soltos, sendo que o bem-estar destes últimos foi maior, devido à condição precária em que o ATA era mantido, com a capacidade de alojamento de cães acima do limite máximo do abrigo. Como os cães da CUASO se distribuiam modulados pelo fornecimento de alimento e abrigo pelos usuários do campus, o manejo adequado destes cães deveria incluir o envolvimento da comunidade, além de sua responsabilização. A reprodução dos cães aversivos precisa ser eliminada, buscando métodos alternativos, devido à dificuldade de captura destes cães. O uso da área de mata destinada a pesquisa por estes cães representa um risco sanitário à comunidade universitária. / The ProMAC emerged within the University of São Paulo in response to a community demand, to address environmental problems, including the presence of stray dogs in its campus. This study aimed to address this program regarding the dynamics and health of the population of stray dogs in the campus and the dogs kept in the campus shelter. Using the technique of photographic mark and recapture, the dog population was estimated in nine occasions in a two years period. In the second year the docile dogs were individually identified and, on four occasions, had biological samples collected (blood, feces and ectoparasites). Dogs housed in the shelter were identified and biological samples were collected in a single effort over three months. The population estimates varied between 14 and 55 dogs, with a non-significant decrease trend over time. The population was mostly composed of males (58.4%), adults (77.8%) and docile individuals (55.7%). The stray population showed changes in hematological parameters throughout the year, consistent with subclinical infection, possibly caused by Hepatozoon canis, which had a significant increase in its prevalence. All dogs were negative for Leishmania sp., Rickettsia sp., Ehrlichia sp. There was no significant difference between either the MAT (Leptospira sp, between 14 and 50% -. campus and 52.4% - shelter) or the elimination of Ancylostoma sp. eggs in feces (between 21 and 55% - campus and 27% - shelter), between dogs from campus and shelter, and the risk of infection in the university community was considered low. Environmental analysis established that the stray dogs main food source are the human food given to them close to food selling points, which is a concern given that more than half of these dogs are positive for Toxoplasma sp. (from 54 to 60%) and would be risk indicators to humans. The aversive stray dogspopulation showed reproductive signs (8.7% of females per year), but the puppies were not found possibly due to low survival rate. Adults, both from docile and the aversive population, had good body condition, low mortality and the docile dogs left the campus more often due to adoption. The data indicated that the health of dogs housed in the shelter were similar to the stray population, and the welfare of the latter is higher due to the precarious condition that the shelter was maintained and the number of dogs kept being over the maximum capacity. As stray dogs were distributed and maintained by the food and shelter supplied by the campus users, the proper management of these dogs would include community involvement and responsibility. The reproduction of aversive dogs must be eliminated, seeking alternative methods, because of the difficulty of catching these dogs. Use of research forest area by these dogs poses a risk to the university community.

The work presented focuses on bacterial zoonoses in northern Nigeria, and more specifically on brucellosis in the Kachia grazing reserve (KGR) - rangeland set-aside by the government to sedentarise Fulani pastoralists. The objectives of the study were to 1) undertake demographic and socioeconomic profiling of the KGR community; 2) review the evidence for brucellosis burden in Nigeria; 3) assess the suitability and performance of brucellosis diagnostic tests selected for use; 4) compare burden of brucellosis across different species (animal and human) and determine Brucella species present in KGR; 5) explore social or environmental factors which may promote or prevent brucellosis transmission; 6) make recommendations for brucellosis control in the KGR and Nigeria; 7) explore community perception of disease and determine household expenditure on animal health; 8) critically evaluate the system’s, integrated, disease cluster, ‘One Health’ approach applied in this study. Three surveys comprising animal (cattle, sheep and goat) and human sampling, administration of questionnaires, focus group discussions and key informant interviews were undertaken in March, June and October 2011. A population census was undertaken in June 2011. Comparison of 2010 government census data with June 2011 census data showed that a mass immigration event occurred in April-May 2011 as a result of post-election violence, with cattle and human populations increasing by 75%. Questionnaire and census data demonstrated the diversity and heterogeneity of the Fulani community in terms of wealth status (roughly corresponding to livestock assets), household size and composition and livelihood diversification strategies. While Fulani in grazing reserves were assumed to be sedentary, KGR households were found to practice wide-range dry and wet season transhumance. Cattle productivity parameters and herd dynamics were similar to those reported by other authors for the extensive pastoralist systems in the sub-humid zone. Herd increase over a one-year period was found to be low or negative for most households in this low input, low output system. Brucellosis epidemiology in the KGR involves B. abortus biovar 3a with low individual and moderate cattle herd prevalence and occasional spill-over into small ruminants. No human brucellosis was detected despite over 80% of the KGR population consuming raw milk and engaging in risky behaviours, raising questions about the potential lower virulence of the local biovar. Low infection rates in livestock, disease-reducing intuitive behaviours or immunity may also be at play. The RBT was found to perform well under field conditions, despite poor concordance when applied in different laboratories and under different conditions. Prospects for control/elimination of brucellosis in the KGR are poor, but low animal burden and absence of human disease render vaccination uneconomic. A review of the literature in Nigeria suggests that brucellosis burden is higher in intensive livestock production systems, which should be targeted first. A laissez-faire approach to brucellosis control in the nomadic pastoralist domain may appeal to policy-makers, as interventions in migratory populations are difficult. Brucellosis is perceived by the KGR community as the number three-priority disease, after trypanosomiasis and Fasciola gigantica/clostridial infection and this was reflected in household expenditure on chemotherapeutics and prophylaxis. Finally, the value of the One Health approach is the ability to see the whole picture, including disease impacts in the animal reservoir as well as the human population, without which erroneous epidemiological and economic conclusions may be drawn; for example, presence of brucellosis in the animal reservoir does not necessarily indicate presence of human disease. This work shows that moving from disciplinary silos to a more holistic or system’s approach spanning epidemiology, evaluation of diagnostic and control tools as well as socio-economic, cultural and institutional aspects can lead to more appropriate recommendations for disease control.

Orientador: Adolorata Aparecida Bianco Carvalho / Coorientador: Karina Paes Bürger / Banca: Luciano Melo de Souza / Banca: Ana Paula Rodomilli Grisolio / Resumo: A raiva ainda é considerada uma doença negligenciada e um grave problema de Saúde Pública, responsável por milhares de mortes anualmente, tanto de animais como de seres humanos. No Brasil, o Ministério da Saúde considera os estudantes de Cursos de Medicina Veterinária como grupo com risco de exposição permanente ao vírus da raiva devido às atividades ocupacionais exercidas durante a graduação, incluindo aulas práticas, estágios curriculares e extracurriculares. Atualmente, no Estado de São Paulo, há 43 cursos de Veterinária computados pelo CFMV, os quais estão distribuídos por 32 municípios. Por esse motivo, o presente estudo teve como propósito realizar diagnóstico de situação sobre a PArPrE para estudantes dos cursos de graduação em Medicina Veterinária do Estado de São Paulo, avaliando-se os riscos e elaborando um modelo de programa de imunização pré-exposição que poderá ser utilizado em todos os cursos de Veterinária do Brasil. Para tanto, foram desenvolvidos e aplicados questionários individuais aos responsáveis pela profilaxia dos alunos em 23 instituições de ensino que demonstraram interesse em participar da pesquisa; foram analisadas as matrizes curriculares dos cursos de graduação priorizando as disciplinas práticas relacionadas aos períodos de risco de exposição ao vírus da raiva; foi delineado o perfil epidemiológico da doença no Brasil e no Estado de São Paulo; e foi feita a associação geográfica dos casos positivos com a localização das instituições de ensino. Ob... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Rabies has still considered a neglected disease and a serious Public Health problem, which is responsible for thousands of animals and humans deaths' every year. In Brazil, the Ministry of Health considers students of Veterinary course as a group at risk of permanent exposure to rabies virus, due to occupational activities during graduation, including practical classes, curricular and extracurricular internships. In 2018, the Federal Council of Veterinary Medicine considered, in the State of São Paulo, 43 Veterinary Medicine courses distributed in 32 municipalities. For this reason, the present study aimed to realize a situational diagnosis on pre-exposure prophylaxis of rabies to Veterinary... (Complete abstract click electronic access below) / Mestre

No description available.

Nous proposons dans cette thèse une nouvelle approche de géosimulation multi-niveau permettant de simuler la propagation d’une zoonose (maladie infectieuse qui se transmet des animaux aux humains) à différents niveaux de granularité. Cette approche est caractérisée entre autres par l’utilisation d’un modèle théorique original que nous avons nommé MASTIM (Multi-Actor Spatio-Temporal Interaction Model) permettant de simuler des populations contenant un nombre considérable d’individus en utilisant des modèles compartimentaux enrichis. MASTIM permet de spécifier non seulement l’évolution de ces populations, mais également les aspects relatifs aux interactions spatio-temporelles de ces populations incluant leurs déplacements dans l’environnement de simulation géoréférencé. Notre approche de géosimulation multi-niveau est caractérisée également par l’utilisation d’un environnement géographique virtuel informé (IVGE) qui est composé d’un ensemble de cellules élémentaires dans lesquelles les transitions des différents stades biologiques des populations concernées, ainsi que leurs interactions peuvent être plausiblement simulées. Par ailleurs, nous avons appliqué nos travaux de recherche au développement d’outils d’aide à la décision. Nous avons acquis une première expérience avec le développement d’un outil (WNV-MAGS) dont l’objectif principal est de simuler les comportements des populations de moustiques (Culex) et des oiseaux (corneilles) qui sont impliquées dans la propagation du Virus du Nil Occidental (VNO). Nous avons par la suite participé au développement d’un outil générique (Zoonosis-MAGS) qui peut être utilisé pour simuler la propagation d'une variété de zoonoses telles que la maladie de Lyme et le VNO. Ces outils pourraient fournir des informations utiles aux décideurs de la santé publique et les aider à prendre des décisions informées. En outre, nous pensons que nos travaux de recherche peuvent être appliqués non seulement au phénomène de la propagation des zoonoses, mais également à d’autres phénomènes faisant intervenir des interactions spatio-temporelles entre différents acteurs de plusieurs types. / We propose in this thesis a new multi-level geosimulation approach to simulate the spread of a zoonosis (infectious disease transmitted from animals to humans) at different levels of granularity. This approach is characterized by using an original theoretical model named MASTIM (Multi-Actor Spatio-Temporal Interaction Model) which can be applied to simulate populations containing a huge number of individuals using extended compartmental models. MASTIM may specify not only the evolution of these populations, but also the aspects related to their spatio-temporal interactions, including their movements in the simulated georeferenced environment. Our multi-level geosimulation approach take advantage of an informed virtual geographic environment (IVGE) composed of a set of elementary cells in which the transitions of the different biological stages of the involved populations, as well as their interactions can be simulated plausibly. Furthermore, this approach has been applied to develop decision support tools. We got a first experience with the development of WNV-MAGS, a tool whose main purpose is to simulate the populations’ behavior of mosquitoes (Culex) and birds (crows), which are involved in the spread of West Nile Virus (WNV). We subsequently participated in the development of a generic tool (Zoonosis-MAGS) that can be used to simulate the spread of a variety of zoonoses such as Lyme disease and WNV. These tools may provide useful information to help public health officers to make informed decisions. Besides, we believe that this research can be applied not only to the spread of zoonoses, but also to other phenomena involving spatio-temporal interactions between different actors of different types.

Emerging infectious diseases (EID) pose a serious threat to global public health. Computational epidemiology is a nascent subfield of public health that can provide insight into an outbreak in advance of traditional methodologies. Research in this dissertation will use fuse nontraditional, publicly available data sources with more traditional epidemiological data to build and parameterize models of emerging infectious diseases. These methods will be applied to avian influenza A (H7N9), Middle Eastern Respiratory Syndrome Coronavirus (MERS-CoV), and Ebola virus disease (EVD) outbreaks. This effort will provide quantitative, evidenced-based guidance for policymakers and public health responders to augment public health operations. / Ph. D.

La géosimulation est une approche qui permet la modélisation et la simulation de phénomènes dynamiques. Elle est appliquée dans un grand nombre de domaines tels que l’urbanisme, la gestion de l’environnement et la santé publique. La géosimulation se base sur des données géo-référencées qui fournissent le contexte spatial virtuel de la simulation. La dynamique du phénomène simulé est généralement fondée sur des modèles, des algorithmes et/ou des équations mathématiques. Dans le domaine de la santé publique qui nous concerne ici, plusieurs approches de simulation ont été proposées pour simuler la propagation des maladies vectorielles ou zoonoses. Une zoonose est une maladie propagée par un virus ou une bactérie transmise par des insectes (ex. moustiques, tiques) à des animaux (rongeurs, oiseaux, mammifères) qui peuvent être infectés, et à leur tour transmettre le virus ou la bactérie à des insectes sains qui les piquent. Éventuellement les insectes peuvent aussi piquer les humains et leur transmettre la maladie. Dans ces approches, on représente habituellement la dynamique de la zoonose par des modèles mathématiques (dits ‘à base de compartiments’) en faisant l’hypothèse que l’espace est homogène. Ainsi elles ne tiennent pas compte de l’influence du ‘paysage’ (en particulier de la couverture du sol). Pourtant prendre en compte les caractéristiques spatiales est important si on veut simuler de façon plausible la dynamique des zoonoses en tenant compte des zones favorables à la survie ou à la prolifération de certaines espèces (ex. moustiques, tiques) de leur dispersion par les espèces transportrices (ex. oiseaux, chevreuils) et de leurs comportements de mobilité. Dans le projet ZoonosisMAGS, dans lequel s’insère ce travail de maîtrise, on vise à développer une approche générique de simulation de la propagation des zoonoses en utilisant des données géo-référencées et en créant un environnement géographique virtuel efficace pour tenir compte de l’influence de la couverture du sol. Pour la dynamique du phénomène qui reflète l’évolution des espèces (des stades œuf, larve, nymphe à adulte), leurs interactions et leur statut épidémiologique (sain, susceptible, infecté) on utilise un modèle enrichi à base de compartiments qui représente les stades d’évolution biologiques et épidémiologiques des différentes espèces impliquées dans la zoonose. Les populations de chaque espèce en interaction et à divers stades de maturité sont associées aux cellules qui représentent les unités de l’environnement géographique virtuel. La transition des individus d’une espèce d’un compartiment à un autre, ainsi que l’interaction entre les espèces se fait à travers des calculs d’expressions mathématiques à chaque pas de simulation, et ceci pour chaque cellule. Par exemple, dans le cadre d’une simulation de la propagation de la maladie de Lyme sur 365 jours d’une année, sur une région d’environ 300km2, on doit évaluer environ 150 expressions mathématiques pour une trentaine de compartiments et environ 20000 cellules à chaque pas de temps. On comprend qu’un défi majeur est celui de l’efficacité de la spécification et de l’évaluation des expressions mathématiques. Aussi, nous traitons dans ce mémoire une première problématique qui concerne la spécification et l’évaluation efficace des expressions mathématiques et booléennes pour de telles simulations. C’est dans ce contexte que nous avons développé un système qui permet à l’usager de spécifier les expressions mathématiques requises par de telles simulations, ainsi qu’un système qui les évalue par la suite de manière très efficace. La spécification des modèles de compartiments des espèces, de leurs interactions et de l’infection peut être une tâche complexe pour certaines zoonoses comme la maladie de Lyme. À cet effet, nous avons traité une deuxième problématique visant à simplifier la tâche de spécification des modèles en créant un module graphique couplé au système d’expressions mathématiques. En nous basant sur la librairie de dessin Visio, nous avons développé un tel système qui est complètement intégré au simulateur ZoonosisMAGS (version C++). Dans ce mémoire nous présentons le contexte de la recherche, les étapes d’analyse et de conception des systèmes développés. Nous montrons à travers des cas d’utilisation comment ces systèmes sont pratiquement utilisés grâce aux interfaces utilisateurs pratiques que nous avons développées. Nous rendons compte de tests d’efficacité qui ont été conduits pour montrer la contribution de notre travail à travers les résultats d’exécution des expressions mathématiques dans une simulation utilisant un modèle à base de compartiments de la maladie de Lyme.