Mosquitoes (Culicidae) transmit several parasites and pathogens including the causative agent of malaria, haemosporidians (Haemosporida). Transmission of these agents to and from the mosquito occurs during the collection of a blood meal. Because of this, it is imperative to gather data on current feeding patterns of mosquitoes. Prior to this study there were no published data on current feeding patterns of mosquitoes in Mississippi. Mosquitoes were captured with CDC light traps at eleven sites in two collection years. Engorged females were analyzed for blood meal content, and the vertebrate host was identified to species level in 72 mosquitoes. Previously published haemosporidian data were gathered to compare potential transmission of haemosporidians to and from the vertebrate and mosquito hosts identified in this study.

O estudo das fontes alimentares em culicídeos possui evidentes significados ecológicos e epidemiológicos, pois auxilia na identificação de animais possivelmente envolvidos na manutenção de surtos epidêmicos das doenças transmitidas por vetores, oferecendo informações para a indicação de potenciais reservatórios de patógenos. Entre os métodos utilizados para avaliar o possível grau de atração exercido por certas fontes de alimentação em relação às fêmeas de culicídeos, a técnica de Reação em Cadeia da Polimerase (PCR) se destaca como sendo uma das técnicas mais eficientes na detecção de repastos sanguíneos devido à alta sensibilidade e especifidade. O objetivo desse estudo foi descrever o perfil alimentar das fêmeas de culicídeos capturadas nos parques Alfredo Volpi, Anhanguera, Carmo, Chico Mendes, Ibirapuera, Santo Dias e Shangrilá, situados na cidade de São Paulo, investigando possíveis associações entre as espécies de mosquitos e suas respectivas fontes alimentares, analisando assim o comportamento no âmbito alimentar dessas espécies em diferentes localidades da cidade, durante os meses de Fevereiro de 2011 à Fevereiro de 2012. A identificação do repasto sanguíneo foi realizada por meio da técnica de PCR para os seguintes hospedeiros: aves, cães, gatos, humanos, primatas ( não humanos) e roedores em 510 fêmeas ingurgitadas distribuídas em 14 espécies capturadas pleas técnicas de aspiração, CDC copa, CDC solo e armadilha de Shannon. Dos vertebrados, apenas o hospedeiro gato não foi encontrado como sendo fonte de repasto, as demais têm sido utilizadas como fontes de alimentação para os culicídeos nos parques estudados. Baseando-se em testes estatísticos não se encontrou nenhuma tendência de associação entre as espécies de culicídeos capturadas ingurgitadas e as fontes utilizadas para repasto, evidenciando assim, padrões aleatórios por parte dos mosquitos em se alimentarem de fontes sanguíneas mais abundantes ou mais fáceis de serem abordadas, reforçando a característica oportunista das fêmeas de culicídeos em busca das suas fontes de alimentação sanguíneas. Sendo de fundamental importância tais informações em contexto epidemiológico, afim de, identificar novos possíveis hospedeiros e reservatórios de patógenos em cadeias de transmissão de doenças transmitidas por culicídeos / The study of the blood meal sources in culicids has evident ecological and epidemiologic meanings, because assists in the identification the possible animals involved in maintenance of epidemic outbreaks of the vector-borne diseases, offering information to indicate the potential pathogen reservoirs. Among the methods used to evaluate the possible degree of attraction exercised by certain source of meals relative to culicid females, the Polymerase Chain Reaction (PCR) stands out, because it is a more efficient technique in blood meals detected, due to the high sensitivity and specificity. The aim of this study was to describe the food profile of culicid females captured in the Alfredo Volpi, Anhanguera, Carmo, Chico Mendes, Ibirapuera, Santo Dias and Shangrilá parks, located in São Paulo city, investiganting possible associations between mosquito species and their blood meal sources, analyzing the feeding behavior of these species in different localities of city, during the months February 2011 and February 2012. The identification of blood meals was realized by PCR technique for the following vertebrate hosts: avian, dogs, cats, humans, primates (non-human) and rodents in 510 engorged females distributed in 14 species captured by aspirator technique, cup CDC, soil CDC and Shannon trap. Of vertebrates, only cats were not found as source of meal, while the others have been used as blood meals for mosquitoes in the parks. Based in statistical tests, there was no trend of association between culicid engorged species captured and sources of meals, thus evidencing random patterns of mosquitoes to feed on the blood meal sources more abundant or easiest to the addressed, reiforcing the opportuinistc characteristic of the mosquito females in searching blood meals. Being of fundamental importance such information in epidemiological context, in order to identify new hosts and pathogen reservoirs in the chains of transmission of vector borne diseases

O estudo das fontes alimentares em culicídeos possui evidentes significados ecológicos e epidemiológicos, pois auxilia na identificação de animais possivelmente envolvidos na manutenção de surtos epidêmicos das doenças transmitidas por vetores, oferecendo informações para a indicação de potenciais reservatórios de patógenos. Entre os métodos utilizados para avaliar o possível grau de atração exercido por certas fontes de alimentação em relação às fêmeas de culicídeos, a técnica de Reação em Cadeia da Polimerase (PCR) se destaca como sendo uma das técnicas mais eficientes na detecção de repastos sanguíneos devido à alta sensibilidade e especifidade. O objetivo desse estudo foi descrever o perfil alimentar das fêmeas de culicídeos capturadas nos parques Alfredo Volpi, Anhanguera, Carmo, Chico Mendes, Ibirapuera, Santo Dias e Shangrilá, situados na cidade de São Paulo, investigando possíveis associações entre as espécies de mosquitos e suas respectivas fontes alimentares, analisando assim o comportamento no âmbito alimentar dessas espécies em diferentes localidades da cidade, durante os meses de Fevereiro de 2011 à Fevereiro de 2012. A identificação do repasto sanguíneo foi realizada por meio da técnica de PCR para os seguintes hospedeiros: aves, cães, gatos, humanos, primatas ( não humanos) e roedores em 510 fêmeas ingurgitadas distribuídas em 14 espécies capturadas pleas técnicas de aspiração, CDC copa, CDC solo e armadilha de Shannon. Dos vertebrados, apenas o hospedeiro gato não foi encontrado como sendo fonte de repasto, as demais têm sido utilizadas como fontes de alimentação para os culicídeos nos parques estudados. Baseando-se em testes estatísticos não se encontrou nenhuma tendência de associação entre as espécies de culicídeos capturadas ingurgitadas e as fontes utilizadas para repasto, evidenciando assim, padrões aleatórios por parte dos mosquitos em se alimentarem de fontes sanguíneas mais abundantes ou mais fáceis de serem abordadas, reforçando a característica oportunista das fêmeas de culicídeos em busca das suas fontes de alimentação sanguíneas. Sendo de fundamental importância tais informações em contexto epidemiológico, afim de, identificar novos possíveis hospedeiros e reservatórios de patógenos em cadeias de transmissão de doenças transmitidas por culicídeos / The study of the blood meal sources in culicids has evident ecological and epidemiologic meanings, because assists in the identification the possible animals involved in maintenance of epidemic outbreaks of the vector-borne diseases, offering information to indicate the potential pathogen reservoirs. Among the methods used to evaluate the possible degree of attraction exercised by certain source of meals relative to culicid females, the Polymerase Chain Reaction (PCR) stands out, because it is a more efficient technique in blood meals detected, due to the high sensitivity and specificity. The aim of this study was to describe the food profile of culicid females captured in the Alfredo Volpi, Anhanguera, Carmo, Chico Mendes, Ibirapuera, Santo Dias and Shangrilá parks, located in São Paulo city, investiganting possible associations between mosquito species and their blood meal sources, analyzing the feeding behavior of these species in different localities of city, during the months February 2011 and February 2012. The identification of blood meals was realized by PCR technique for the following vertebrate hosts: avian, dogs, cats, humans, primates (non-human) and rodents in 510 engorged females distributed in 14 species captured by aspirator technique, cup CDC, soil CDC and Shannon trap. Of vertebrates, only cats were not found as source of meal, while the others have been used as blood meals for mosquitoes in the parks. Based in statistical tests, there was no trend of association between culicid engorged species captured and sources of meals, thus evidencing random patterns of mosquitoes to feed on the blood meal sources more abundant or easiest to the addressed, reiforcing the opportuinistc characteristic of the mosquito females in searching blood meals. Being of fundamental importance such information in epidemiological context, in order to identify new hosts and pathogen reservoirs in the chains of transmission of vector borne diseases

Le MALDI-TOF MS (Matrix Assisted, Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry) est une technique protéomique qui est utilisée en routine pour l’identification des microorganismes dans les laboratoires de microbiologie. Ainsi, dans ce travail nous avons évalué le MALDI-TOF MS pour l’identification du repas sanguin des moustiques. Dans la première partie de notre travail, une revue bibliographique a été effectuée sur les différentes méthodes (sérologiques, biologie moléculaire) connues dans les études de préférence trophiques des arthropodes. La deuxième partie fut l’optimisation du MALDI-TOF MS pour l’identification de l’origine du repas sanguin des moustiques. Pour l’optimisation, Anopheles gambiae Giles et Aedes albopictus ont été artificiellement nourris sur le sang de plusieurs hôtes vertébrés en utilisant l’appareil Hemotek durant deux heures sous les conditions standard. Nos résultats ont montré que la comparaison des spectres provenant des moustiques nourris sur le même type de sang révèle une grande reproductibilité des profils protéiques. L’interrogation des MS spectres contre la base de données a révélé une identification correcte de l'origine du repas sanguin pour les spécimens collectés moins de 24 heures après la prise du repas sanguin. Pour les échantillons collectés sur le terrain, le MALDI-TOF MS a permis de détecter dans le repas de sang des moustiques une grande diversité d’hôtes domestiques. En conséquence la technique MALDI-TOF MS serait un outil efficace pour les études de surveillance épidémiologique des maladies vectorielles et l'identification de la préférence trophique de spécimens fraichement gorgés. / MALDI-TOF MS (Matrix Assisted, Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry) is a proteomic technique that routinely used for microorganisms identification in clinical microbiology laboratory. Recently, the MALDI-TOF MS was successfully used as a innovative tool for arthropod identification. Thus, in this work we evaluated the MALDI-TOF MS to identify the blood meal sources from engorged mosquitoes. In the first part of our work, a bibliographical review was carried out on the different methods (serological, molecular biology) known in the trophic preference determination of hematophagous arthropods. The second part was optimization of the MALDI-TOF MS for identifying the origin of the blood meal of mosquitoes. For optimization, the Anopheles gambiae Giles and Aedes albopictus were artificially fed on several vertebrate hosts blood using the Hemotek device for two hours under standard conditions. Our results showed intra-species reproducibility and inter-species specificity of MS spectra from mosquitoes engorged on the same or different vertebrate hosts. The MS spectra querying against the database reveal a correct identification of the the blood meal origin from the specimens collected less than 24 hours post-feeding. For field samples, MALDI-TOF MS allowed to detect the mosquitoes blood meal fed on wide variety of domestic hosts. Consequently the MALDI-TOF MS technique would be an effective tool for epidemiological surveys of vector-borne diseases and the identification of the trophic preference of mosquito freshly engorged.

Avec la mise en place des politiques de conservation des espèces sauvages, l'extension de l'urbanisation et l'accroissement des populations humaines, le contact homme-faune a considérablement augmenté au cours de ces dernières décennies. Par conséquent, le nombre de maladies d'origines zoonotiques a explosé avec six apparitions d'agents infectieux par an, dont 75% sont susceptibles d’être transmises par un vecteur. La plupart de ces maladies n'ayant pas encore de vaccins, les principales méthodes d'évitement sont basées sur les stratégies de lutte anti-vectorielle adaptées à l'écologie et au comportement alimentaire des vecteurs. Au Gabon, particulièrement dans les parcs nationaux, nous avons identifié six espèces de glossines (Glossina palpalis palpalis, G. fuscipes fuscipes, G. fusca congolense, G. pallicera newsteadi, G. caliginea et G tabaniformis) vivant principalement en milieux forestiers, six espèces de stomoxes (Stomoxys calcitrans, S. inornatus, S. niger niger, S. niger bilineatus, S. omega omega et S. transvittatus) inféodées aux milieux ouverts types forêt secondaire, savane et villages. Nous avons également identifié six espèces de tabanides (Ancala sp., Atylotus sp., Chrysops sp., Haematopota sp., Tabanus par et T. taeniola), mais leur distribution n'était pas claire dans les milieux prospectés. Par ailleurs, nous constatons que ces mouches hématophages ont un régime alimentaire très diversifié, comprenant les mammifères terrestres et aquatiques, les reptiles et les oiseaux. Elles se nourrissent à 86% sur la faune, contre seulement 14% sur l'homme. Cependant, dans les milieux anthropisés les repas sanguins d'origine humaine sont très importants, notamment dans les villages (100%) et autour des camps de recherche implantés dans les parcs (24%). Ainsi en l'absence de faune dans le milieu, ces mouches hématophages se nourrissent sur l'homme. Comme 75% des maladies émergentes chez l'homme proviennent de la faune sauvage et que près de ¾ d'entre elles circulent via le sang, elles sont donc susceptibles d’être détectées dans les repas sanguins de mouches hématophages. Cette technique d'échantillonnage non-invasif de la faune sauvage semble être un bon moyen d'identifier les agents infectieux à ADN (plasmodiums et trypanosomes), mais reste encore imprécise pour les agents infectieux à ARN (arbovirus). / The contact between human and wild fauna has considerably increased during these last decades due to the increase of human population size but also to conservation policies. As a consequence, the number of zoonotic diseases soared with a mean of six new infectious diseases per year, 75% of whom being vectorially transmitted. The way to avoid the human contamination by these emergent diseases is based on the efficient vector control resulting from a deep knowledge of the ecology and the feeding behavior of the different vector species. During our work, we have identified and characterized the ecology of 6 tsetse species (Glossina palpalis palpalis, G. fuscipes fuscipes, G. fusca congolense, G. pallicera newsteadi, G. caliginea and G. tabaniformis) that live in forests and 6 stomoxe species (Stomoxys calcitrans, S. inornatus, S. niger niger, S. niger bilineatus, S. omega omega and S. transvittatus) that live in and around (anthropized places) conservation areas. We have also identified 6 tabanid species (Ancala sp., Atylotus sp., Chrysops sp., Haematopota sp., Tabanus par and T. taeniola). The feeding ecology of the tsetse species have been studied through the determination of host extracted from blood meals in the insect caught with molecular techniques. These hematophagous insects had a diversified diet that was constituted of diverse mammal species but also reptiles and birds. The food intake results mostly from wild fauna (86%) and more rarely from humans (14%). However, in anthropised habitats (villages and research’s camps within the parks), the blood intakes from human origin were important, in particular in the villages (100%), suggesting that without wild fauna the flies shift on human host. In the last part of our work, we tried to identify pathogens in the blood samples extracted from the tsetse species in order to test whether these species could be used as living sampling syringe of the wild fauna. This new proposed non-invasive sampling techniques allowed to detect the DNA of various infectious agents (plasmodiums and trypanosomes), but failed to detect the RNA of viruses (arbovirus) suggesting that this approach could be useful but need to be improved.