Academic literature on the topic 'Canine leishmaniasia'

Background: Leishmaniasis is a chronic infectious disease caused by intracellular protozoan Leishmania that affects canine and human. The visceral leishmaniasis (VL) is caused by the Leishmania donovani complex, in which canines are the main reservoir for human VL. In Southern Brazil, case reports of this disease have increased, especially when canines are infected in endemic areas in the country. Canines usually present a systemic disease, characterized by cutaneous lesions, weight loss, generalized lymphadenopathy, hepatomegaly and splenomegaly. This report aims to describe the clinicalpathological features of a case of autochthonous VL in a canine of an urban area of Porto Alegre.Case: A male, mixed breed, dog , 7 year-old, resident at the East Side of Porto Alegre, living together with two other canines, presented at clinical examination progressive weight loss, associated with hyporexia and hyperthermia, evolving to lateral recumbency, paralisys, and death. At necropsy, the dog was cachectic with diffusely pale mucosae. Gross findings included liver enlarged, with multifocal firm brownish areas, spleen enlarged, showing multifocal firm round dark-red areas, and kidneys diffusely pale with evidentiated tranversal striations on cortical zone. At microscopic examination, there was on the spleen diffuse inflammatory infiltrate of macrophages with large cytoplasm containing multiple amastigotes. The liver, exhibited atrophy of hepatocytes and moderate multifocal inflammatory infiltrate in sinusoids of macrophages containing multiple amastigotes. These features were also observed moderately on lymph nodes and lamina propria of large intestine. Immunohistochemistry examination showed marked positive staining for Leishmania spp. in amastigotes located whitin the cytoplasm of macrophages of spleen, liver, lymph nodes and large intestine.Discussion: Canine leishmaniasis is a disease that affects both internal organs and skin. However, the condition is called VL mostly because it is associated with the same species that cause the visceral form in humans. In this case the canine presented liver, spleen and lymph node lesions; however no skin lesion was observed during the clinical examination. A serological evaluation of canids in East Side of Porto Alegre performed in 2005 showed that 3.5% of these dogs were positive for Leishmania; yet neither of these animals presented clinical signs. This demonstrates that the agent was already present, however only 3-10% of the canines infected develop clinical disease. In non-endemic areas VL is related to the migration of canids from endemic areas, where VL is common. However the canine here described was born, raised, and was living in Porto Alegre. Lutzomyia longipalpis is the main vector of VL and despite its wide distribution it was identified only in 2009 in Rio Grande do Sul State. Autochthonous cases of VL were reported in canines and humans in this state, confirming the hypothesis that the vector was widely distributed and it is now present in Porto Alegre, keeping the epidemiological cycle of that disease active. Canine VL occurs prior in humans, since canines are the main domestic reservoirs and are critical for the maintenance of this disease cycle. This is the first autochthonous VL in a canine of an urban area of Porto Alegre; therefore authorities should be alert, and new control measures must be taken to avoid the canine leishmaniasis outbreak due to its potential for zoonotic transmission.Keywords: leishmaniasis, canine, protozoan, immunohistochemistry.

ABSTRACT Leishmaniases, which are important causes of morbidity and mortality in humans and dogs, are extremely difficult to treat. Antimicrobial peptides are rarely used as alternative treatments for naturally acquired parasitic diseases. Here we report that the acylated synthetic antimicrobial peptide Oct-CA(1-7)M(2-9) is safe and effective for treating naturally acquired canine leishmaniasis.

Canine Leishmaniasis is widespread in various Mexican states, where different species ofLeishmaniahave been isolated from dogs. In the present study, we describe the detection ofL. braziliensis, L. infantum,andL. mexicanain serum of dogs from the states of Yucatan and Quintana Roo in the Yucatan Peninsula (Mexico). A total of 412 sera were analyzed by ELISA using the total extract of the parasite and the iron superoxide dismutase excreted by different trypanosomatids as antigens. We found the prevalence ofL. braziliensisto be 7.52%,L. infantumto be 6.07%, andL. mexicanato be 20.63%, in the dog population studied. The results obtained with ELISA using iron superoxide dismutase as the antigen were confirmed by western blot analysis with its greater sensitivity, and the agreement between the two techniques was very high.

Diante da variedade de ectoparasitos, pulgas e carrapatos têm importância como vetores e na sua constante presença causando infestações em cães, estes artrópodes durante a alimentação de um hospedeiro parasitado fazem a manutenção do ciclo do agente infeccioso. Potencialmente, se pode associar a presença desses ectoparasitas e a positividade em cães para leishmaniose. A Leishmaniose Visceral Canina (LVC) é uma zoonose endêmica no Brasil, estando presente em todas as cinco regiões do país. Com o intuito de contribuir para trabalhos posteriores na associação da presença de ectoparasitas em cães com leishmaniose, objetivou-se demonstrar a porcentagem de cães soropositivos atendidos na Clínica Veterinária da Universidade Anhanguera Uniderp, no período de 2017 a 2019, em que foram encontrados carrapatos ou pulgas durante a consulta clínica. A seleção da população canina ocorreu por conveniência, de acordo com a demanda espontânea de atendidos na Clínica Veterinária. Foram selecionados somente caninos soropositivos para Leishmaniose Visceral Canina. Foram analisadas fichas de 415 cães identificados como soropositivos a prevalência de 8,41% dos cães atendidos em consonância com outros resultados que relatam a alta prevalência da LVC na região Centro-Oeste. Neste estudo, avaliando a presença de pulgas e carrapatos, dos 415 cães soropositivos para leishmaniose a prevalência de infestação por ectoparasitos foi de 34%. Estudos sobre a presença de carrapatos e pulgas em cães positivos para leishmaniose e outras enfermidades devem ser feitos regularmente, podendo ajudar no entendimento da transmissão desses agentes e facilitar assim o controle e prevenção das doenças zoonóticas. Palavras-chave: População Canina. Zoonoses. Carrapatos. Pulgas. Abstract Given the variety of ectoparasites, fleas and ticks are important as vectors and in their constant presence causing infestations in dogs; these arthropods during the feeding of a parasitized host maintain the infectious agent cycle. It is possible to potentially associate the presence of these ectoparasites and positivity in dogs for leishmaniasis. Canine Visceral Leishmaniasis (LVC) is an endemic zoonosis in Brazil, presenting itself in all the five regions of the country. In order to contribute to further research upon associating the presence of ectoparasites in dogs with leishmaniasis, the objective was to demonstrate the percentage of positive dogs attending the Veterinary Clinic of Anhanguera Uniderp University, between 2017 and 2019, in which ticks or fleas were found during the clinical consultation. The selection of the canine population carried out based on convenience, according to spontaneous demand of those attended at the Veterinary Clinic. Only seropositive dogs for Canine Visceral Leishmaniasis were selected. Records of 415 dogs identified as seropositive were analyzed; the prevalence was 8.41% of the dogs seen, matching other results that report this high prevalence of CVL in the Midwest region. In this study presence of fleas and ticks was assessed, and in all the 415 seropositive dogs for leishmaniasis, the prevalence of ectoparasite infestation was 34%. Studies on the presence of ticks and fleas in dogs positive for leishmaniasis and other diseases should be carried out regularly, which may help in understanding the transmission of such agents and thus facilitate controlling and preventing zoonotic diseases. Keywords: Canine population. Zoonoses. Ticks. Fleas.

Leishmaniasis is a vector-borne disease withLeishmania chagasibeing the etiological agent of canine visceral leishmaniasis in South America. Canine venereal tumor is a transplantable round cell tumor of histiocytic origin which is mostly observed in sexually active male and female intact dogs. It has been shown thatLeishmaniaamastigotes have higher tropism for the canine male genital tract tissues and venereal leishmaniasis transmission has been documented in dogs but, to date, a canine venereal tumor-dependent transmission route has not been fully demonstrated. In this report, a 10-year-old, mixed breed, intact female dog presented a vaginal venereal transmissible tumor but no other clinical abnormalities otherwise. Unexpectedly, tumor tissue imprint smears examination revealedLeishmaniasp. amastigotes within infiltrating macrophages. In addition to the cytological direct identification, the protozoan was confirmed within the neoplastic tissue by means of immunohistochemistry and polymerase chain reaction. This report illustrates an asymptomaticLeishmaniasp. infection that may have started on or from the canine venereal tumor tissue, the latter option further supporting previous evidence of such an alternative vector-independent route of transmission for canine visceral leishmaniasis in areas where these diseases coexist.

Four dogs infected with Leishmania had proliferative lesions on the mucosae of the penis, tongue, oral cavity, prepuce, or nose. These mucosal, nodular lesions produced by parasites of the genus Leishmania have not been described previously in the dog. Leishmaniasis should be considered in the differential diagnosis of tumor-like lesions of mucous membranes.

La leishmaniasis es una infección parasitaria que afecta a humanos, animales domésticos y silvestres. Es causada por los miembros del género Leishmania que realizan parte de su ciclo biológico en un hospedador vertebrado, en forma aflagelar o amastigote. Y completan su desarrollo en el tubo digestivo del hospedador invertebrado, en su forma flagelar o promastigote, estos son flebótomos del género Phlebotomus en el Viejo Mundo y Lutzomyia en el Nuevo Mundo (Miró, 2007b; Baneth, 2006, 2007). En varios países de América el principal vector de leishmaniasis visceral es Lutzomyia longipalpis, su distribución abarca desde el sur de México hasta el norte de Argentina y es capturada dentro y fuera de las viviendas humanas (Milleron et al., 2004; Lainson y Rangel, 2005; González et al., 2006; Ramírez et al., 2006; Dantas, 2008; Diniz et al., 2008). La leishmaniasis está distribuida en el sur de Europa, África, Asia, América del sur, centro y recientemente en Estados Unidos y Canadá (Baneth, 2007). En el mundo hay 14 millones de personas infectadas y cada año se registran 2 millones de casos nuevos. De ellos 500,000 viscerales, que provoca más de 50,000 defunciones; y 1´500,000 casos cutáneos. La población en riesgo se eleva a 350 millones de personas y sólo en 33 de los 88 países endémicos la leishmaniasis es una enfermedad de notificación obligatoria (OMS, 2007). Los cambios ecológicos, demográficos y medioambientales relacionados con nuevos proyectos de desarrollo, urbanización y grandes movimientos de población están conduciendo a un aumento a escala mundial de consecuencias sanitarias adversas donde el desarrollo del flebótomo vector se ve favorecido, de tal manera que la aparición de casos parece estar relacionada con la continua deforestación y la expansión urbana, que se ha intensificado en los últimos años. Posicionándose como un problema de salud pública cada vez más acusado en muchas regiones de Latinoamérica, especialmente en Brasil, Colombia y Venezuela, donde anteriormente no se encontraba (Desjeux, 2002; Rondón, 2006; ENY-740S, 2007; Sousa y Pearson, 2009). El rol del perro (Canis familiaris), como reservorio en la transmisión doméstica y peri doméstica de la leishmaniasis humana ha sido reconocida desde que Charles Nicoles, el ganador al premio Nobel, descubrió la enfermedad en perros en Tunisia en 1908. El número de perros infectados en Sud América es estimado en millones con una alta tasa de infección en algunas áreas de Brasil y Venezuela (Killick-Kendrick, 1999; Baneth, 2006, 2007; Sousa y Pearson, 2009). La leishmaniasis canina es una enfermedad zoonótica que existe en cerca de 50 de los 88 países donde la leishmaniasis humana está presente y resulta frecuentemente mortal en humanos y perros no tratados (Baneth, 2006; Coura et al., 2006). En la población canina afectada los signos clínicos son muy variables, podemos observar desde animales aparentemente sanos, hasta otros que manifiestan varios signos clínicos. Esto se debe a la complejidad de los mecanismos patogénicos dependientes del parásito y a la marcada individualidad de la respuesta inmunitaria del hospedador (Miró, 2007b). Los términos que utilizaremos como abreviación para leishmaniasis canina será Lcan, en esta especie la piel se ve afectada en el transcurso de la diseminación de la enfermedad a los órganos internos, manifestándose ambas formas de la enfermedad a la vez (Killick-Kendrick, 1999; Baneth, 2006; Miró, 2007b; OIE, 2008). Para designar la enfermedad según sus manifestaciones clínicas en humanos, usaremos las siguientes abreviaciones: leishmaniasis cutánea (LC), leishmaniasis mucocutánea (LMC) y leishmaniasis visceral (LV) (Killick-Kendrick, 1999; Baneth, 2006). La presente monografía pretende ser un documento actualizado donde se revisa la enfermedad en todos sus aspectos, para aumentar los conocimientos existentes sobre esta zoonosis parasitaria de creciente interés en los últimos veinte años.
Tesis

Zoonotic visceral leishmaniasis (ZVL) is a fatal disease caused by the sandfly-borne intracellular protozoan parasite Leishmania infantum, and vaccine development in the reservoir host (the domestic dog) is a current research priority. The aims of this study were (1) to conduct safety and immunogenicity trials of two candidate vaccines in dogs, and (2) to compare and demonstrate the utility of immunological and molecular tools for measurement of vaccine efficacy in naturally exposed dogs. DNA/ modified vaccinia virus Ankara (MVA) prime/boost canine vaccines expressing the Leishmania proteins TRYP and LACK were safe, and elicited a type-1 cytokine response, in vivo delayed-type hypersensitivity and IgG2 class responses, consistent with superior protective immunogenicity of TRYP over LACK. However, inconsistent associations were found between progressive disease in infected dogs and IgG class levels, prompting caution in use of the latter as a proxy for protective immunogenicity. Specific serological responses in vaccinated dogs did not cross-react with an unrelated diagnostic antigen rK39, and responses to crude parasite antigen (CLA) were minimal, enabling serological detection of infection incidence in vaccinated dogs. Particularly in early stage infection, CLA ELISA was more sensitive than rK39 ELISA and an rK39-based rapid diagnostic test, though rK39 serology was sensitive for diagnosis of symptomatic clinical cases. A commercially available PCR kit incorporating a rapid oligochromatographic detection step was tested for the first time in dogs, and proved highly sensitive for detection of ZVL infection in bone marrow, comparable to existing nested PCR methods. Molecular methods were investigated as proxy measures to replace labour-intensive xenodiagnosis for detection of the infectiousness of dogs to biting sand flies. Conventional and real-time PCR of tissues from naturally infected dogs were sensitive tests to identify infectiousness, but showed low to moderate specificity. Recommendations are made to improve the application of molecular methods as proxy measures of infectiousness and hence vaccine efficacy.

Les leishmaniosis són un grup de malalties causades per protozous del gènere Leishmania que es transmeten per vectors. La leishmaniosi visceral (LV) humana pot ser mortal si no es tracta, resultant en 26 000-65 000 morts a l’any. Els cànids són el principal reservori i hostes de Leishmania infantum, l’agent causant de la LV zoonòtica a la conca mediterrània. Es desconeixen els mecanismes que regulen el resultat final de la infecció, però és sabut que el sistema immunitari juga un paper clau en el control de la malaltia. Diversos estudis han demostrat que la vitamina D té un rol important en la resposta immune, activant el sistema immunitari innat i modulant la resposta adaptativa. A més, s’ha descrit la relació entre la deficiència de vitamina D i el risc de patir diverses malalties. L’objectiu de la tesis va ser estudiar si la vitamina D té una contribució rellevant en la leishmaniosi canina (LCan). Per això, es va mesurar la concentració de vitamina D en mostres de sèrum d’una població de gossos sans i malalts residents en zona altament endèmica i se’n va estudiar la relació amb paràmetres parasitològics i immunològics. Els gossos malalts presentaven nivells de vitamina D significativament més baixos que els no infectats i que els infectats asimptomàtics. A més, la deficiència de vitamina D es correlacionava amb paràmetres relacionats amb la progressió de la LCan. També vam investigar si variacions genètiques en el locus del gen del receptor de la vitamina D s’associa amb la progressió de la LCan, però les freqüències al·lèliques dels polimorfismes (SNPs) trobats no van resultar ser estadísticament diferents entre grups. Llavors, vam analitzar la concentració de vitamina D en mostres de sèrum preses en diferents períodes de l’any en una cohort de gossos sans. Els resultats van mostrar que no hi ha variació estacional dels nivells de vitamina D en gossos. També es va analitzar retrospectivament la concentració de vitamina D en gossos amb leishmaniosi clínica i gossos no-infectats a l’inici de l’estudi, quan tots els animals eren negatius a Leishmania, i un any després. Mentre que els gossos sans no van mostrar canvis en els nivells de vitamina D durant l’estudi, els que van desenvolupar leishmaniosi van mostrar una reducció significativa al final de l’estudi. Per tant, la concentració de vitamina D no és un factor de risc per desenvolupar LCan, sinó que disminueix amb el curs de la malaltia. Un model in vitro va demostrar que afegir vitamina D activa (1,25(OH)2D3) comporta una reducció significativa de la càrrega de L. infantum en macròfags canins. Analitzant l’expressió de gens relacionats amb la via de la vitamina D en monòcits canins primaris vam demostrar que l’expressió de la β-defensina CBD103 augmenta significativament amb l’addició de 1,25(OH)2D3. Els resultats van corroborar que la vitamina D juga un paper en el control del paràsit. Per últim, es va estudiar la viabilitat de la vitamina D com a adjuvant per potenciar l’efecte d’una vacuna enfront la leishmaniosi. Es va administrar vitamina D conjuntament amb una vacuna d’ADN encapsulada en liposomes a ratolins BALB/c. Dues setmanes després de la vacunació els animals van ser infectats amb L. infantum. Es va mesurar la càrrega parasitària en òrgans diana i es va avaluar la resposta immune abans de la infecció i sis setmanes després. La vacuna no va reduir significativament la càrrega parasitària, però amb la co-administració de vitamina D es va apreciar una tendència a disminuir-la. L’estudi de la resposta immunològica va suggerir que l’augment de limfòcits T CD4+ i CD8+ podrien haver contribuït en la protecció parcial aconseguida per la vacuna amb la vitamina D com a potenciador.
Las leishmaniosis son un grupo de enfermedades causadas por protozoos del género Leishmania que se transmiten por vectores. La leishmaniosi visceral (LV) humana puede ser mortal si no se trata, resultando en 26 000-65 000 muertes por año. Los cánidos son el principal reservorio y huéspedes de Leishmania infantum, el agente causante de la LV zoonótica en la cuenca mediterránea. Se desconoce el mecanismo que regula el resultado final de la infección, pero se sabe que el sistema inmunitario juega un papel clave en el control de la enfermedad. Varios estudios han demostrado que la vitamina D tiene un rol importante en la respuesta inmune, activando el sistema inmunitario innato y modulando la respuesta adaptativa. Además, se ha descrito la relación entre la deficiencia de vitamina D y el riesgo de sufrir algunas enfermedades. El objetivo de la tesis fue estudiar si la vitamina D tiene una contribución relevante en la leishmaniosis canina (LCan). Para ello se determinó la concentración de vitamina D en muestras de suero de una población de perros sanos y enfermos de leishmaniosis residentes en una zona altamente endémica y se estudió la relación de ésta con parámetros parasitológicos e inmunológicos. Los perros enfermos mostraron niveles de vitamina D significativamente más bajos que los no infectados y que los infectados asintomáticos. Además, la deficiencia de vitamina D se correlacionó con parámetros relacionados con la progresión de la enfermedad. También investigamos si las variaciones genéticas en el locus del gen del receptor de la vitamina D se asocia con la progresión de LCan, pero las frecuencias alélicas de los polimorfismos (SNPs) encontrados no resultaron ser estadísticamente diferentes entre grupos. Posteriormente se analizó la concentración de vitamina D en muestras de suero tomadas en diferentes periodos del año en una cohorte de perros sanos. Los resultados mostraron que no hay una variación estacional de los niveles de vitamina D en perros. También se analizó retrospectivamente la concentración de vitamina D en perros con leishmaniosis clínica y perros no infectados al inicio del estudio, cuando todos los animales eran negativos a Leishmania, y un año después. Mientras que los perros sanos no mostraron cambios en los niveles de vitamina D durante el estudio, los que desarrollaron leishmaniosis mostraron una reducción significativa al final del estudio. Por lo tanto, la concentración de vitamina D no es un factor de riesgo para desarrollar LCan, sino que disminuye con el curso de la enfermedad. Un modelo in vitro demostró que añadir vitamina D activa (1,25(OH)2D3) conlleva una reducción significativa de la carga de L. infantum en macrófagos caninos. Analizando la expresión de genes relacionados con la vía de la vitamina D en monocitos caninos primarios demostramos que la expresión de la β-defensina CBD103 aumenta significativamente con la adición de 1,25(OH)2D3. Los resultados corroboraron que la vitamina D juega un papel en el control del parásito. Por últimos, se estudió la viabilidad de la vitamina D como adyuvante para potenciar el efecto de una vacuna frente la leishmaniosis. Se administró vitamina D junto a una vacuna de ADN encapsulada en liposomas a ratones BALB/c. Dos semanas después de la vacunación los animales se infectaron con L. infantum. Se determinó la carga parasitaria en órganos diana y se evaluó la respuesta inmune antes de la infección y seis semanas después. La vacuna no redujo significativamente la carga parasitaria, pero con la coadministración de vitamina D se apreció una tendencia a reducirla. El estudio de la respuesta inmunológica sugirió que el aumento de linfocitos T CD4+ y CD8+ podrían haber contribuido a la protección parcial conseguida cuando se administró vitamina D como potenciador junto a la vacuna.
Leishmaniasis are a group of neglected vector-borne diseases caused by obligate intracellular protozoan parasites of the genus Leishmania. Human visceral leishmaniasis (VL) can be fatal if left untreated, resulting in 26 000-65 000 deaths per year. Canids are the main reservoir and hosts of L. infantum, the causative agent of zoonotic VL in the Mediterranean Basin. The mechanisms that regulate the outcome of the infection are undisclosed, although it is well known that immune system plays a key role in leishmaniasis disease control. Several studies have shown that vitamin D plays an important immunomodulatory role by activating innate immune system and modulating the adaptive immune response. Furthermore, the relationship between vitamin D deficiency and the risk of suffering from a plethora of health disorders has been described. The aim of the thesis was to study if vitamin D have a relevant contribution in canine leishmaniasis (CanL). Because of that, we measured vitamin D concentration in serum samples from a cohort of healthy and ill dogs from a highly endemic area and we have also studied the relationship of vitamin D concentration with parasitological and immunological parameters. The sick dogs presented significantly lower vitamin D levels than their non-infected and the asymptomatic counterparts. In addition, vitamin D deficiency correlated with several parameters linked to leishmaniasis progression. We also aimed to investigate whether genetic variation within the vitamin D receptor gene locus is associated with the progression of CanL, but the allelic frequencies of the four single nucleotide polymorphisms (SNPs) found were not statistically different between groups. Afterwards, we analysed retrospectively vitamin D concentration in serum samples from a cohort of healthy dogs collected in different periods of the year. The results showed that there is not a seasonal variation of vitamin D concentration in dogs. We also analysed retrospectively vitamin D concentration in serum samples from dogs with clinical leishmaniasis and non-infected healthy dogs, in which we measured vitamin D levels at the beginning of the study, when all dogs were negative for Leishmania, and 1 year later. Whereas non-infected dogs showed no changes in vitamin D levels along the study, those developing clinical leishmaniasis showed a significant vitamin D reduction at the end of the study. Therefore, vitamin D concentration is not a risk factor for developing canine leishmaniasis, but it diminishes with the onset of clinical disease. An in vitro model using a canine macrophage cell line proved that adding active vitamin D (1,25(OH)2D3) leads to a significant reduction in L. infantum load. Analyzing expression of genes related to vitamin D pathway on primary canine monocytes, we showed that defensin CBD103 expression was significantly enhanced after active vitamin D addition. The in vitro results corroborated that vitamin D plays a role in parasitic control. Finally, we studied the suitability of vitamin D as an adjuvant to enhance the effect of a DNA vaccine against VL. BALB/c mice were treated with vitamin D concomitantly with a DNA vaccine encapsulated in liposomes. Two weeks after vaccination, the animals were infected with L. infantum parasites. Parasite load was measured in target tissues and immune response was evaluated before challenge and six weeks post-infection. Our DNA vaccine did not significantly reduce parasite load in liver nor spleen, but vitamin D coadministration showed a tendency to diminish parasite load in target organs. The study of cell response in splenocytes suggested that higher levels of CD4+ and CD8+ T cells may be responsible for the partial protection mediated by the DNA vaccine with vitamin D as enhancer.
Universitat Autònoma de Barcelona. Programa de Doctorat en Farmacologia

Orientador: Maria Rita Donalisio Cordeiro
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A Leishmaniose Visceral Americana (LVA) é uma zoonose causada pelo protozoário Leishmania (L.) infantum e transmitida predominantemente pelo flebotomíneo Lutzomyia longipalpis. No meio urbano, o cão doméstico atua como reservatório e fonte de infecção para o homem. A LVA é uma zoonose de caráter reemergente e um grave problema de saúde pública. As estratégias de controle de LVA estão contidas no Programa Brasileiro de Vigilância e Controle (PCLV) e estão centradas no controle do reservatório e vetores e na educação em saúde. Em Campinas, no final do ano de 2009, foi confirmado o primeiro caso de LVA canino autóctone em área de proteção ambiental na região leste da cidade. Após as investigações de foco foram diagnosticados casos adicionais de LVA em cães e identificada a presença do vetor. Com esta ocorrência, passou a ser considerado município com transmissão canina. O objetivo deste trabalho foi descrever a organização espacial do primeiro foco de LVA de Campinas sob as perspectivas ecológica, geográfica e social a fim de obter uma melhor compreensão das interações entre meio ambiente, sociedade, os riscos em saúde pública e as dificuldades na execução do preconizado pelo PCLV. Para avaliar tais dificuldades foi realizado também estudo qualitativo através de entrevistas semi-estruturadas com coordenadores de municípios de grande porte com transmissão canina e/ou humana (Bauru, Belo Horizonte, Campo Grande, Goiânia e Fortaleza) de LVA. Por fim, foi avaliado uso de coleiras impregnadas com deltametrina a 4% como medida para diminuição da prevalência canina e consequentemente evitar casos humanos em Campinas. Os achados neste trabalho mostram que no Brasil as intervenções de saúde pública não têm apresentado resultados positivos na prática uma vez que há descontinuidade das atividades de controle devido a recursos insuficientes para sustentabilidade das ações e há resistência dos sujeitos implicados pela doença, particularmente associados ao reservatório canino e ao controle químico. Avaliou-se também que, embora sejam consideradas estratégicas, as ações de comunicação relacionadas a esse agravo não têm conseguido alcançar os objetivos de estimular a adesão ao programa e evitar desconfortos nas comunidades atingidas. Por fim, o uso de coleiras inseticidas foi considerado positivo como medida auxiliar na diminuição da prevalência canina com boa aceitação da comunidade. E em conclusão, ficou clara a necessidade de reavaliação da política brasileira de controle de LVA para garantia de maior efetividade na prevenção e controle da doença
Abstract: American Visceral Leishmaniasis (AVL) is a zoonosis caused by Leishmania (L.) infantum protozoa and transmitted by the Lutzomyia longipalpis phlebotomus as the main vector. In urban environment, dogs act as a reservoir and source of infection for vectors. American visceral leishmaniasis is a reemerging zoonosis and a serious public health problem. The guidelines of the Brazilian Program of Surveillance and Disease Control (PCLV) have their bases in control of the reservoir, vector and in health education. Campinas was added to the list of municipalities with established canine transmission kept by the state's AVL Surveillance and Control Program in 2009, with the confirmation of the first autochthonous case of canine AVL. Disease notification occurred in a residential lot with good infrastructure and resident population with high socioeconomic status, situated in an environmental protection area of the east part of the city. The present study aims at describing the process of investigation of reservoirs, vectors and environment associated with the outbreak of canine AVL in a grand scale municipality and the difficulties in implementing the measures proposed by PCLV. In order to evaluate these difficulties a qualitative study was also performed through semi-structured interviews with coordinators of large municipalities with canine and / or human transmission (Bauru (SP), Goiania (GO), Campo Grande (MT), Fortaleza (EC) and Belo Horizonte (MG)). Finally was evaluated the use of deltamethrin impregnated collars as a measure to decrease the prevalence of canine AVL and thus avoid human cases in Campinas. The findings in this study show that in Brazil the interventions have not produced positive results in the municipal level. The main problems referred were: discontinuity of the activities and strength of subjects involved by the disease, particularly associated with canine reservoir and housing fumigation. It was evaluated also that, although considered strategic, communication actions have not been able to achieve the goals of encouraging adherence to the program and to avoid discomfort in the affected communities. In conclusion, there is a clear need for reassessment of Brazilian policy for the control and prevention of LV to ensure effectiveness of actions
Doutorado
Epidemiologia
Doutora em Saúde Coletiva

Il microbiota intestinale (insieme dei microrganismi che si trovano all’interno dell’apparato gastroenterico) svolge diverse funzioni e, tra queste, di particolare interesse è il suo rapporto con il sistema immunitario. Infatti, diversi studi hanno evidenziato la presenza di disbiosi non solo in corso di patologie gastroenteriche, ma anche autoimmuni ed infettive. Gli studi in medicina veterinaria sull’argomento sono ancora pochi e proprio per questo motivo, all’interno di questo progetto, è stato scelto di indagare la possibile relazione tra il microbiota intestinale e due particolari patologie infettive (la peritonite infettiva felina -FIP- e la leishmaniosi canina) la cui patogenesi è fortemente influenzata dal tipo di risposta immunitaria sviluppata dall’ospite. Gli scopi di questo progetto sono quindi stati: la valutazione del microbiota intestinale in gatti affetti o meno da FIP (studio I). Dal momento che diagnosi in vivo di FIP risulta spesso difficoltosa, è stato valutato il potenziale, come biomarker di FIP, della paraoxonasi-1, una proteina di fase acuta negativa fortemente influenzata da importanti stati ossidativi (studi II e III). Per lo stesso motivo è stata valutata la correlazione tra le performance diagnostiche di istopatologia, immunoistochimica e RT-PCR su differenti organi (studio IV). Infine, è stata indagata la composizione del microbiota intestinale in cani infetti o meno da Leishmania spp., correlando i risultati ottenuti con le differenti popolazioni leucocitarie valutate mediante citofluorimetria (studi V e VI). I risultati ottenuti da questo progetto hanno fornito delle indicazioni preliminari sulla composizione del microbiota intestinale in gatti affetti da FIP o positivi per Coronavirus, che necessitano però un approfondimento su un gruppo di studio più ampio (studio I). È stato possibile determinare gli intervalli di riferimento della paraoxonasi-1 nel gatto ed evidenziare le sue buone performance come marker diagnostico in corso di FIP (studi II e III). Nonostante l’immunoistochimica rimanga il gold standard per la diagnosi di FIP, l’associazione con RT-PCR potrebbe ridurre gli errori diagnostici, vista la buona correlazione tra le due metodiche (studio IV). Infine, la valutazione della composizione del microbiota e delle popolazioni leucocitarie in cani affetti da leishmaniosi ha messo in luce delle differenze significative sia rispetto ai cani sani, che agli esposti asintomatici. Questi risultati sono incoraggianti e possono fungere da punto di partenza per ulteriori indagini (studi V e VI).
The gut microbiota (consortium of all the microorganisms that inhabit the gastrointestinal tract) plays different roles in the host. Among these, its relationship with the immune system has been of great interest in the last few years. Indeed, several studies highlight the presence of dysbiosis not only in gastrointestinal diseases, but also during autoimmune or infectious diseases. Literature about this topic is scarce in veterinary medicine. Thus, in this project, the possible relationship between gut microbiota and two specific diseases (feline infectious peritonis -FIP- and canine leishmaniasis) was investigated. These diseases were chosen due to the pivotal role of the immune response in their pathogenesis. The aims of this projects were: the evaluation of gut microbiota of cats with and without FIP (study I). Since in vivo diagnosis of FIP is quite challenging, the potential role of paroxonase-1 (a negative acute phase protein strongly influenced by oxidation) as a biomarker of FIP was investigated (studies II-III). For the same reason, the diagnostic agreement among histopathology, immunohistochemistry and RT-PCR on different organs was evaluated (study IV). Finally, the gut microbiota composition in dogs infected or not by Leishmania spp. was investigated. The results were correlated with the leukocyte populations studied by flow cytometry (studies V-VI). Results obtained in this project provided preliminary data about gut microbiota composition in cats affected by FIP or only Coronavirus positive. This achievement needs to be further investigated on a bigger sample size (study I). Paraoxonase-1 reference interval and its good performance as a diagnostic biomarker of FIP were determined (studies II-III). Despite the immunohistochemistry is still the gold standard for FIP diagnosis, the good diagnostic agreement obtained in the study suggested that a possible association with RT-PCR could minimize diagnostic errors (study IV). Finally, the gut microbiota composition and leukocyte populations of leishmaniotic dogs highlighted some significant differences compared with both healthy and exposed asymptomatic dogs. These promising results could be a starting point for further researches (studies V-VI).

Orientador: Ingrid Menz
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A incidência das leishmanioses tegumentar (LTA) e visceral americanas (LVA) em hospedeiros caninos e humanos encontra-se em crescente expansão no Brasil. Para a vigilância epidemiológica dessas endemias, é fundamental o conhecimento da distribuição das diferentes espécies vetoras de flebotomíneos e, para a LVA, o conhecimento de parâmetros epidemiológicos como a prevalência, incidência, período de incubação e potencial de transmissibilidade de Leishmania infantum chagasi no cão, seu principal reservatório. Objetivou-se assim esclarecer alguns aspectos epidemiológicos das infecções caninas, incluindo-se levantamento entomológico no município de Monte Mor, situado na região centro-leste do estado de São Paulo, além da obtenção de parâmetros epidemiológicos da LVA por estudo longitudinal de 105 cães em área endêmica para a doença em Campo Grande, Mato Grosso do Sul, por dois anos. Em Monte Mor, 319 amostras de soro canino foram avaliadas por ELISA e RIFI, sendo todas negativas para anticorpos anti-Leishmania, identificou-se sete espécies de flebotomíneos, com predomínio de Nyssomyia neivai (48,84%) considerada a principal transmissora do agente causador da LTA no interior paulista, além do diagnóstico de dois casos caninos de LTA, com sorologia reagente para ELISA FML e infecção por L. (Viannia) braziliensis. No estudo longitudinal dos 105 cães acompanhados por meio de avaliações clínicas, exames sorológicos (ELISA L. major-like, FML e S7) e parasitológicos diretos (esfregaços e PCR de aspirados de medula óssea e linfonodo e imunoistoquímica de pele) obteve-se prevalência sorológica inicial de 30,40% (145/477) no ELISA L. major-like e 26,28% (97/369) no ELISA FML. A prevalência da doença clínica (sintomáticos) foi de 7,13% (62/870), sendo que 24,53% (117/477) foram soropositivos no ELISA L. major-like, mas sem sintomas de leishmaniose visceral canina (LVC), demonstrando quantidade elevada de cães infectados assintomáticos na área. Ao final de 24 meses não se observou associação estatística significativa nas variáveis ambientais avaliadas no início do estudo e a ocorrência de casos de LVC, como a ocorrência prévia de LVA e/ou LVC no entorno ou na casa do proprietário, a existência de outras espécies animais na casa, o hábito intra ou peridomiciliar, o temperamento, a idade e o sexo do cão. A incidência de novas infecções variou de 11,76% (8/68), 11,76% (8/68) e 18,18% (12/66) respectivamente entre o Dia -30 e Zero, Dia Zero e Mês 12 por sorologia e Dia Zero e Mês 12 para os métodos diretos. A mortalidade natural e induzida via eutanásia de animais doentes e/ou infectados foi de 28,57% (30/105). O período de incubação médio foi de 6,46 meses. Alguns animais infectados com resultados positivos em prova diagnóstica de PCR e/ou prova de sorologia no início do estudo não apresentaram novos resultados positivos após 12 meses, indicando possível cura ou não estabelecimento da infecção. Observaram-se alguns animais com provas diretas positivas mostrando infecção assintomática por período de 24 meses. Obteve-se baixa prevalência de amastigotas em pele saudável, presente apenas em animais sintomáticos, enquanto que a ausência de amastigotas observada em cães portadores assintomáticos indica que os mesmos podem não ter papel importante na transmissão de parasitas ao flebotomíneo vetor
Abstract: Cutaneous (ACL) and visceral american leishmaniasis (AVL) incidences in human and canine hosts are increasing and expanding in Brazil. In order to perform an adequate vigilance of these diseases, the knowledge regarding distribution of different sandfly vector species is mandatory, besides of precising epidemiological parameters like prevalence, incidence, incubation period and potential of transmissibility in the dog, the main reservoir for the AVL etiologic agent. This way, the objectives of this study were to clarify some epidemiological aspects of canine leishmaniases, including entomological surveillance in the county of Monte Mor, central east region of São Paulo state and performance of a longitudinal study in an AVL endemic area located in Campo Grande, Mato Grosso do Sul state, including 105 dogs in order to evaluate epidemiological data during two years. In Monte Mor county, 319 sera samples were analysed through in house developed ELISA and IFA methods. No seropositive result was found, seven different sandfly species were identified, prevailing Nyssomyia neivai (48.84%) considered the main vector for the ACL etiologic agent in São Paulo state countryside, and two dogs were diagnosed with ACL symptoms, presenting seropositivity through ELISA FML and positive identification of L. (Viannia) braziliensis infection using PCR. The longitudinal study was performed using clinical examination, serology (ELISA L. major-like, FML and S7) and direct diagnostic techniques (bone marrow and lymph node smears and PCR and immunohistochemistry in skin tissues) on dogs. A seroprevalence of 30.40% (145/477) at ELISA L. major-like and 26.28% (97/369) at ELISA FML was obtained at the pre-initial phase. Clinical disease prevalence was 7.13% (62/870), and 24.53% (117/477) dogs were seropositive at ELISA L. major-like, but asymptomatic, showing the high amount of infected healthy carriers. At the end of the 24 months period no significant association was found between visceral leishmaniasis (VL) canine cases with environmental variables evaluated at Day Zero like previous registration of human or canine VL on the study house or neighborhood, other domestic animal species at the backyard, intra or peridomiciliar, aggressive behavior, age or sex of the study dog. Incidence of infections varied from 11.76% (8/68), 11.76% (8/68) e 18.18% (12/66) respectively between Day -30 and Zero, Day Zero and Month 12 using serology and Day Zero and Month 12 for direct diagnostic methods. Natural and induced mortality through euthanasia of sick/infected dogs was 28.57% (30/105). The mean disease incubation period was 6.46 months. Some of the infected animals with positive diagnosis at the beggining of the study had no other positive results after 12 months, indicating a possible cure or an absence of infection establishment, while others had positive diagnosis at the beginning and at month 12 with asymptomatic condition for more than 24 months. A low Leishmania amastigotes prevalence at healthy skin was obtained and positive results were observed only in symptomatic animals. Absence of parasites in skin of asymptomatic carriers may indicate they have no important role on the transmission of Leishmania to competent vectors
Doutorado
Parasitologia
Doutor em Parasitologia

The aims of the work presented in this thesis were two-fold: [i) to investigate whether domestic dogs are important reservoir hosts of ACL in a L. [Viannia]-endemic area where domestic transmission to humans has been reported [Part 1]; and [ii] to identify the shortcomings of currently practiced leishmaniasis dog control programmes and to evaluate whether topical insecticides could be used to control canine leishmaniasis [Part 2]. There is a growing belief that dogs [Canis familiaris] are peridomestic reservoirs of American cutaneous leishmaniasis [ACL] , as numerous studies have reported high ACL infection rates in dogs. The work described here is the first longitudinal study of ACL in dogs, and was carried out in 18 Leishmania [Viannia] -endemic villages of the Department of Huanuco, Peru. Over three years [1997-1999] a total 1104 dogs were surveyed, 104 of which prospectively. A polymerase chain reaction [PCR)] protocol to identify L. [Viannia] parasites in dogs was developed [Chapter 2], and, together with serology [ELISA. and IFAT], used to calculate prevalence and incidence of disease [Chapter 4]. The data was used to estimate the basic reproduction number [Ro] [Chapter 4] of canine ACL and to demonstrate a correlation between canine and human ACL incidences in the study villages [Chapter 5]. Several findings presented in Chapters 2-5 suggest that dogs are reservoir hosts of [peri-]domestic L. [Viannia] transmission in Huanuco, Peru. First, whereas the prevalence (3.8%) and incidence of clinical disease [4.2%] are low, the prevalence [25.6%] and incidence [29.0% per year] of L. [Viannia] infection in dogs is comparatively high. Second, the average duration of infection [2.2. years] can be as long as the mean life expectancy of an infected dog [2.5 years]. Third, L. [Viannia] parasites in dogs do not remain localised at the site of inoculation but are able to disseminate to both viscera and mucosa. Fourth, the detection of L. [Viannia] parasites by PCR in the blood of a high proportion of both symptomatic [32%] and asymptomatic [7.5%] dogs suggests that infected dogs are potentially infectious to sandfly vectors. Fifth, after controlling for inter-village differences in transmission rates, household dog ownership was shown to be a significant risk factor for human ACL. The results presented here show that if dogs were the main ACL reservoir host and if L. [Viannia] transmission were homogeneous, a dog control strategy (e.g. culling, insecticide-treated dog collars) in the study villages in Huanuco would be very feasible and effective, because the control effort [i.e. coverage] to reduce Ro<1 would be comparatively small [as low as 47%]. Domestic dogs are established reservoir hosts of ZVL caused by L. infantum. Hence, one of the approaches to reduce the incidence of human ZVL is to target infected dogs. The findings of a comparative study testing topical insecticides and applications to protect dogs from sandfly bites are presented in Chapter 7. It was shown that whilst permethrin and fenthion pour-on lotions had a more immediate effect on sandfly biting rates and mortality, deltamehtrin-impregnated collars [DMC] had a more prolonged protective effect, with the survival rate of bloodfed sandflies reduced by up to 86% after two months of deltamethrin collar application. In the work described in Chapter 8 the effectiveness of DMC to control canine ZVL was tested in a matched cluster intervention trial. Possible constraints associated with a community-wide implementation of a dog collar ZVL control strategy were also investigated using mathematical modelling. Although ZVL incidence was 32% lower in collared as compared to uncollared dogs after five months collar application, the difference was not significant. However, DMC did significantly reduce the odds (by 50%) of dogs increasing their anti-Leishmania antibody titre. Whether topical insecticides such as DMC will be effective as leishmaniasis control tools will depend on several factors. Firstly, the strategy will be most effective in those endemic areas where domestic dogs are the main ZVL reservoir and the epidemiological significance of wild reservoirs or stray dogs contributing to ZVL transmission is negligible. Secondly, in order to achieve a significant epidemiological impact on ZVL transmission, high dog collar coverage rates are essential. This will not only require the rapid replacement of lost collars, but also the collaring of new dogs recruited into the population; where population turnover rates are high, maintaining high coverage rates will be a greater logistic challenge, which invariably applies to dog populations in tropical, ZVL-endemic countries. Ultimately, the decision to replace the dog culling strategy with community-wide application of DMC will depend on [i] the relative cost of the interventions; and [ii] the practical applicability of DMC in the field [e.g. the willingness of the community to apply DMC and the efficiency with which they replace collars which have detached]. Clearly, the implementation of DMC on dogs is more likely to have the consent of the population at risk than the highly unpopular dog culling policy that continues to be practised in some ZVL-endemic countries.

Orientador: Maria Jaqueline Mamprim
Resumo: A literatura veterinária possui escasso conteúdo a respeito do uso da ultrassonografia e elastossonografia para caracterização de lesões em linfonodos de cães. O objetivo do primeiro estudo foi comparar as características ultrassonográficas e elastossonográficas entre 50 linfonodos neoplásicos (LN) e 69 linfonodos não neoplásicos (LNN), em cães, com base no diagnóstico microscópico. A hipótese desse estudo é que seja possível distinguir lesões neoplásicas e não neoplásicas com tais técnicas de imagem. Variáveis quantitativas foram comparadas entre os grupos com teste t de student não pareado e, as variáveis categóricas, com teste U de Mann-Whitney. Linfonodos neoplásicos apresentaram dimensões significativamente maiores, relação entre eixo curto e eixo longo (RECEL) superior, maior frequência na perda da arquitetura interna, distribuição vascular predominante mista, índices de resistividade (IR) e de pulsatilidade (IP) superiores e maior rigidez à distribuição do escore elastográfico, em comparação com LNN. O objetivo do segundo estudo foi descrever as características ultrassonográficas e elastossonográficas de 25 linfonodos caninos parasitados por Leishmania spp. A hipótese desse estudo é que seja possível padronizar linfonodos contendo formas amastigotas de Leishmania spp por meio da ultrassonografia e elastografia. Houve aumento nas dimensões dos linfonodos, com RECEL próximo da normalidade. Observou-se alta prevalência de contornos irregulares, bordas nítidas e ausência d... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Applicability of ultrasonography and sonoelastography for characterization of lymph node lesions has not been established. The aim of the first study was to compare sonographic and sonoelastographic features between 50 neoplastic and 69 non-neoplastic lymph nodes of dogs, categorized according to microscopy. We hypothesize that sonography and sonoelastography allow the differentiation between neoplastic and non-neoplastic lymph node lesions. Quantitative variables were compared using Student’s unpaired t test and categoric variables were assessed using non-parametric Mann-Whitney U test. Neoplastic nodes had larger size, and short-to-long axis, predominantly mixed vascular flow distribution (hilar and peripheral) on Color Doppler and on Power Doppler, higher resistivity and pulsatility indices, and higher stiffness (score predominantly 4) on elastographic chromatic scale in comparison with non-neoplastic lymph nodes. The aim of the second study was to describe sonographic and elastosonographic features of 25 canine lymph nodes parasitized with Leishmania spp. We hypothesize that sonography and sonoelastography allow standardization of lymph nodes with Leishmania spp. There was enlargement of the lymph nodes associated with maintenance of the shape. Most of the nodes had irregular contour, well-defined borders and absent hilar tissue definition. A minority of the nodes had heterogeneous uniformity due to focal hypoechoic areas or peripheric hypoechoic areas. Vascular flow dist... (Complete abstract click electronic access below)
Doutor

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FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO
Canine babesiosis and canine visceral leishmaniasis (CVL) are vector borne diseases, where dogs exert a play as reservoir or source for arthropods responsible by the transmission of these protozoosis. Babesia canis vogeli, is transmited by tick Rhipicephalus sanguineus while Leishmania infantum (sin. Leishmania chagasi) is transmited by sand fly (Lutzomyia longipalpis). The results showed that CVL remains endemic in São Luís Municipality. Despite that the coinfection between Leishmania and Babesia was low considering that both diseases are endemic in this tropical area. Beside that was observed that Yorkshire terrier presented higher predisposition to acquire the infection by B. canis vogeli. A remarkable result was the occurrence of ocular lesions associated to L. infantum infection.
A babesiose canina e a leishmaniose visceral canina são doenças transmitidas por vetores, sendo os cães competentes reservatórios e fonte alimentar dos artrópodes envolvidos. Babesia canis vogeli, é um parasita intraeritrocitário transmitido pelo carrapato Rhipicephalus sanguineus. Leishmania infantum (sin. Leishmania chagasi) transmitidos a mamíferos pela picada dos flebotomíneos (Lutzomyia longipalpis), infectando macrófagos do Sistema Fagocítico Mononuclear do hospedeiro. O presente trabalho é divido em capítulos e os resultados encontrados mostraram que a leishmaniose visceral canina ainda é endêmica no município de São Luís, e que apesar disso a taxa de coinfecção com Babesia foi baixa. Também foi observado que a raça Yorkshire terrier, dentre as raças estudadas, apresentou maior predisposição para contrair a infecção por B. canis vogeli. Outro resultado significativo foi a ocorrência de lesões oculares associadas à infecção por L. infantum.

Canine Leishmaniasis (CanL) is due to Leishmania infantum (syn. Leishmania chagasi) and is endemic in Mediterranean countries, Portugal, Latin America and Southern Asia. In the last few decades, imported and even autochthonous cases have been recorded in traditionally non-endemic areas such as Central and Northen Europe and Northen America. This is possibly due to a wider spread of the vector and especially to a larger numbers of travelling dogs. Many studies about CanL have been published in the last years and have contributed in understanding different aspects of this disease, including the alternative ways of transmission and the pathologic mechanisms underlying the clinical findings. However, CanL still remains a very challenging disease to diagnose, treat and prevent. Moreover, it is still very difficult to predict the outcome given the low numbers of controlled studies evaluating markers of prognosis. So, the main aims of the present thesis were to investigate new clinico-pathological aspects of CanL and to possibly identify useful prognostic factors. The first study demonstrated that a significant proportion of dogs with leishmaniasis have increased serum cTnI concentration, suggesting that CanL can cause cardiac disease, mainly myoand endocarditis. In the second study, the iron status and its relationship with C-reactive protein (CRP) was for the first time investigated in CanL. The results indicated that dogs with leishmaniasis have decreased serum iron, total iron-binding capacity (TIBC), unsaturated iron-binding capacity (UBIC) and percentage of transferrin saturation and increased concentrations of ferritin. Increased CRP and decreased TIBC are also risk factors for moratility. Finally, since the disease is progressively changing its geographical distribution, the last investigation was conducted in the United Kingdom (UK), currently considered a non-endemic country. The majority of dogs that were diagnosed of leishmaniasis have been adopted from an endemic area (especially from the Mediterranean countries) respect a minority that have travelled to those regions. No autochthonous cases were recognised. Purebreed dogs and those that were classified in stage D according to the Canine Leishmaniasis Working Group guidelines were at higher risk of death. Differently to what has been reported in endemic countries, serology titre at diagnosis and IRIS staging for chronic kidney disease did not influence the outcome.

Visceral leishmaniasis is a zoonosis of great importance due to its incidence and high lethality, and the dog as its main reservoir in urban centers. Furthermore, environmental characteristics such as soil with abundant organic matter can predispose local ecosystems to the development of the vector Lutzomyia longipalpis. This study aimed to carry out a data collection in partnership with the Health Department of the municipality of Vassouras, determining environmental characteristics and favorable means for the dissemination of the sand fly, in an area of 150 meters from a confirmed human case of leishmaniasis in the Itakamosi neighborhood. During the months of October and November 2021, an environmental study was carried out in 7 homes, where a total of 14 dogs lived. Through questionnaires, data were collected regarding the environmental conditions of these homes. It was observed that 100% of the animals lived in households close to the forest and vegetation. Of the 7 households analyzed (6/7), 85,71% had banana trees in their surroundings, followed by the presence of fruit trees, which corresponds to (5/7) 71,42% of households. In contrast, in (3/7), 42,83% and (2/7) 28,57% represent the number of houses with the presence of chicken coops and kennels, respectively. In contrast, in (1/7) 14,28% of the households, there was the presence of organic matter debris, aiding in the sand fly cycle. The animals residing in these houses were tested for leishmaniasis and showed a negative result, but the possibility of future infection of these animals cannot be ruled out, given that these factors corroborate the easy adaptation of the sandfly exploiting the accumulation of organic matter in areas of socioeconomic vulnerability.

Canine Visceral Leishmaniasis (CVL) is a disease caused by the protozoan genus Leishmania and transmitted by the bite of the sand fly mosquito. It is considered a zoonosis and its control is based on the diversity of urban vector reservoir agents, where dogs are the main reservoirs of the parasite. The present article aimed to investigate the prevalence and incidence of CVL in different regions of Brazil, from a literature review. An analysis of scientific articles focusing on the epidemiological, clinical, diagnostic, prophylaxis and control aspects of the disease was carried out. The prevalence of CVL in Brazilian regions is determined by means of clinical, epidemiological and laboratory diagnostic methods. Laboratory confirmation is necessary to avoid false positive results, whose consequences can be fatal, such as euthanasia in non infected animals. The study is based on the survey of transmission areas with the evaluation of the effectiveness of actions to control and progress the disease, such as the reduction of prevalence and lethality, with measures of interventions and environmental sanitation that can reduce its incidence. It was found that the knowledge of the epidemiological indicators of CVL are essential to implement health actions to promote control and prevention in susceptible populations.

Canine visceral leishmaniasis (CVL) is a disease with a great impact on public health in Brazil due to its zoonotic potential. One of the biggest challenges in controlling the disease is the fact that its main reservoir in urban areas is the domestic dog, and thus, it is a source of infection that lives very close to the human being. This study aimed to determine the seroprevalence of L. chagasi and the symptoms of CVL present in dogs living near a human case confirmed by the Municipal Health Department of the municipality of Vassouras. Blood samples were collected from the cephalic vein of 14 resident dogs within a radius of 150 meters from a confirmed human case. This collected material was submitted to the DPP screening test, and the positive samples were submitted to the ELISA confirmatory test. Information was also obtained through questionnaires about the presence of the disease's clinical signs. Of the 14 animals tested in the DPP, only 4 were positive in the screening test, and all presented negative results in the ELISA confirmatory test. Of the 14 dogs, 4 had symptoms. Of these, 2 presented skin lesions, and 1 animal showed cough, while the last one exhibited vomiting. It is concluded that the DPP screening test for CVL is a practical and easy to handle method, although it requires attention due to the possibility of cross-reaction with other etiological agents in dogs. The human case is probably a result of a non-autochtone infection. Therefore, asymptomatic dogs should be under disease surveillance since these hosts also act as a source of infection for vector insects.