RESUMO
BACKGROUND OBJECTIVES: In Brazil, one of the visceral leishmaniasis control measures in urban environments is the elimination of Lutzomyia longipalpis, which occurs through the application of pyrethroid insecticides with residual action in homes and outbuildings. Due to the loss of sensitivity of this vector to these insecticides, the search for more efficient insecticide compounds against L. longipalpis has been intensified. The objective of this work was to evaluate the toxicity of Trixis vauthieri essential oil on adult sandflies of the species L. longipalpis, and identify the phytochemical composition of these essential oils. METHODS: Essential oils from leaves collected from T. vauthieri at different times were obtained at concentrations of 5, 10 and 20 mg/mL. Twenty sandflies were exposed to the essential oils and the mortality was evaluated after 1, 2, 4, 16, 24, 48 and 72 h. The chemical constituents of the essential oil were also identified. RESULTS: The essential oils of T. vauthieri at a concentration of 20 mg/mL were the most toxic to sandflies, reaching a mortality rate of 98.33% and 95%, respectively, after 72 h of exposure. The analysis of chemical constituents revealed the presence of triterpenes and/or steroids, tannins, flavonoids, alkaloids, saponins and coumarins. INTERPRETATION CONCLUSION: The results obtained suggest that T. vauthieri essential oil is fairly promising as an insecticidal potential against L. longipalpis. A more detailed analysis of the oil's phytochemical composition is necessary to identify active and pure compounds that can be used in vector control of visceral leishmaniasis.
Assuntos
Insetos Vetores , Inseticidas , Leishmaniose Visceral , Óleos Voláteis , Psychodidae , Animais , Psychodidae/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Inseticidas/farmacologia , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/transmissão , Brasil , Insetos Vetores/efeitos dos fármacos , Folhas de Planta/química , Feminino , Óleos de Plantas/farmacologia , Óleos de Plantas/químicaRESUMO
The identification of parasite fauna can contribute to the assessment of the health status of sea turtles, and thus make it possible to develop effective management and treatment strategies aimed at conserving these animals. The present study aimed to investigate the parasite fauna in sea turtles rescued in six sections of the coast of Santa Catarina and Paraná (Brazil) from January 2020 to December 2022 through the recording of exam reports available in the Information System of Aquatic Biota Monitoring. In total, records of 334 sea turtles were analyzed during this period, of which 219 (65.6 %) were infected with at least one parasite. Chelonia mydas was the most frequent species with 86.5 % of rescues and presented the highest species richness. At least 43 species belonging to 36 different genera have been recorded parasitizing sea turtles. The most common helminths were Cricocephalus albus, Metacetabulum invaginatum, Pronocephalus obliquus, with 12.3 %, 8.7 % and 8.4 %, respectively, while protozoa of the genus Entamoeba were the most prevalent in the turtles analyzed (8.1 %). An interesting finding was the unprecedented finding of Hymenolepis sp. eggs in faeces of some turtle species. The results showed that the parasite fauna was quite diverse, with several species known to be capable of harming the physical health and well-being of sea turtles. In view of this, it is necessary to adopt strategies for monitoring the health of the different rescued species with a view to conserving sea turtles in Brazilian territory.
Assuntos
Parasitos , Tartarugas , Animais , Brasil , Poluição Ambiental , BiotaRESUMO
BACKGROUND: Porteirinha is endemic for visceral leishmaniasis (VL), with intense disease transmission of the disease. We evaluated the impact of canine euthanasia as a single control measure on the incidence of VL in humans and canines. METHODS: A prospective observational cohort study was carried out over four years (1998-2002) in 8 of the 12 neighborhoods of the city. The dynamics of canine visceral leishmaniasis (CVL) transmission were evaluated for 2 years, before beginning the screening-culling intervention. The comparative morbidity index (CMI) was used to stratify areas with the greatest risk of CVL, and the spatial distribution of human and canine VL cases was compared using univariate and bivariate K-functions. RESULTS: Human cases conglomerated in three neighborhoods. Spatial clusters were detected for CVL in 1998, 2000, and 2001, but not in 1999, when greater spatial dispersion occurred. The screening and culling intervention reduced the number of human VL cases and decreased the incidence of CVL, mainly in neighborhoods with a high CMI. CONCLUSIONS: The systematic euthanasia of seropositive dogs was shown to be an effective control action of the Program for Control of Visceral Leishmaniasis (PCLV) in Brazil. The fundamental role of domestic dogs in the epidemiological chain of VL was reaffirmed.
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Abstract The geographical distribution of leishmaniasis has undoubtedly expanded, and is now being reported to be in areas that were previously non-endemic. This study therefore aimed to investigate whether there is any variation in the structure and in the composition of phlebotomine communities along an environmental gradient - from a mesic to a xeric environment, across different climatic periods (rainy and dry seasons). Furthermore, we test whether there were differences in sex ratio of sand flies between wet and dry environments. A total of 535 specimens of sand flies belonging to 18 species were recorded. Richness, abundance, and composition of species were significatively higher in the xeric environment (semidecidual Forest) compared to the mesic environment (Riparina Forest). We unveiled site specific differences in sand fly collections since the community composition changes with the geographic distance among the sampling points. These results led to the conclusion that for sand flies species, the environmental conditions available for each species could be different within the habitat taking into account the degree of humidity in the forest as well as the climatic season (dry or wet). The present study gives a valuable contribution to the knowledge of sand flies, as a group of insects, from the Atlantic Forest biome.
Resumo A distribuição geográfica das leishmanioses, sem dúvida, tem se expandido, e agora está sendo relatada em áreas previamente consideradas como não endêmicas. Assim, este estudo teve como objetivo investigar se existe alguma variação na estrutura e na composição das comunidades de flebotomíneos ao longo de um gradiente ambiental - em habitats classificados como mesicos e xericos, em diferentes períodos climáticos (chuva e seca). Além disso, testamos se havia diferenças na razão sexual entre ambientes mais umidos e mais secos. Um total de 535 espécimes de flebotomíneos pertencentes a 18 espécies foram registradas. Riqueza, abundância e composição de espécies foram significativamente maiores nos habitats xericos (Floresta semidecidual) em comparação com os habitats mesicos (Floresta Ciliar). Revelamos diferenças específicas entre os habitats, nas assembleias de flebotomíneos, uma vez que a composição da comunidade muda com a distância geográfica entre os pontos de amostragem. Estes resultados levaram à conclusão de que as condições ambientais disponíveis para cada espécie de fletomonineo varia dentro do habitat, tendo em conta o grau de umidade na floresta assim como a estação climatica (seca-chuva). O presente estudo dá uma contribuição valiosa para o conhecimento da fauna de flebotomíneos, no bioma Mata Atlântica.
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Intestinal parasites are a major public health problem in developing countries, most prevalent in areas where sanitation is poor and the population's hygiene is inadequate. They affect people of all ages, although school-age children are the most susceptible. In this study, we investigated the presence of intestinal parasites in the shared environments of a public school in the town of Diamantina, Minas Gerais State. From December 2012 to February 2013, samples were collected for three months (once a month) by using the Graham method (1941), in duplicate, by affixing a 6 x 5 cm clear tape, six times in each collection site, in a space of about 30 cm2. Then, each tape was positioned longitudinally on a microscope slide and the identification of the biological forms of the parasites was performed with the aid of a 40X objective from an optical microscope. Eleven sites were selected for sampling. Cysts of Entamoeba coli were the most frequently found in this study (50%), followed by Hymenolepis diminuta eggs (27.6%), Iodamoeba butschllii cysts (5.6%), Ascaris lumbricoides eggs (5.6%), Taenia species eggs (5.6%) and hookworm eggs (5.6%). The highest positivity rates were found in the samples drawn from the cafeteria's eating table. The results have indicated the need to improve the cleaning in the school environments, as well as the development of educational practices that may help in the preservation of public health.
Assuntos
Fezes/parasitologia , Helmintíase/epidemiologia , Enteropatias Parasitárias/epidemiologia , Infecções por Protozoários/epidemiologia , Adolescente , Animais , Brasil/epidemiologia , Criança , Feminino , Helmintíase/diagnóstico , Helmintíase/parasitologia , Humanos , Enteropatias Parasitárias/diagnóstico , Enteropatias Parasitárias/parasitologia , Masculino , Prevalência , Infecções por Protozoários/diagnóstico , Infecções por Protozoários/parasitologia , Fatores de RiscoRESUMO
The aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis(82.1%) and Lutzomyia cortelezzii(17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission.
Assuntos
Comportamento Alimentar/fisiologia , Insetos Vetores/fisiologia , Psychodidae/fisiologia , Animais , Brasil , Galinhas , Cães , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Insetos Vetores/classificação , Leishmaniose Cutânea/transmissão , Leishmaniose Visceral/transmissão , Masculino , Psychodidae/classificação , Roedores , Estações do AnoRESUMO
SUMMARYThe aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis(82.1%) and Lutzomyia cortelezzii(17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission.
RESUMOO objetivo deste estudo foi identificar o repasto sanguíneo de fêmeas de flebotomíneos capturadas no município de Governador Valadares, área endêmica de leishmaniose visceral e tegumentar no Estado de Minas Gerais, Brasil. Entre maio de 2011 e janeiro 2012 foram realizadas capturas com armadilhas luminosas HP em quatro bairros. Foram capturados 2.614 exemplares (2.090 machos e 524 fêmeas). Noventa e sete fêmeas ingurgitadas foram identificadas como pertencentes às espécies Lutzomyia longipalpis(82,1%) e Lutzomyia cortelezzii(17,9%). Considerando a alimentação simples e a mista, o ensaio imunoenzimático revelou em Lutzomyia longipalpisuma predominância de sangue de galinhas (43,6%), mostrando o importante papel que galinhas podem exercer no peridomicílio, aumentando a chance de contato dos flebotomíneos com outros vertebrados e, consequentemente, o risco de transmissão da leishmaniose.
Assuntos
Humanos , Animais , Masculino , Feminino , Cães , Comportamento Alimentar/fisiologia , Insetos Vetores/fisiologia , Psychodidae/fisiologia , Brasil , Galinhas , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática , Insetos Vetores/classificação , Leishmaniose Cutânea/transmissão , Leishmaniose Visceral/transmissão , Psychodidae/classificação , Roedores , Estações do AnoRESUMO
BACKGROUND: Sand fly collections were performed to study ecological aspects of the Phlebotominae fauna of the Xakriabá Indigenous Reserve, an area with endemic cutaneous leishmaniasis, located in the state of Minas Gerais, Brazil. METHODS: The collections were performed in peridomicile areas and along trails previously selected for the study of wild and synanthropic Leishmania hosts. Differences in the distribution patterns of the sand fly species as well as in species richness and abundance between the different ecotopes were investigated during both rainy and dry seasons over the course of the study period. RESULTS: A total of 8,046 sand flies belonging to 11 genera and 28 species were collected. Lutzomyia longipalpis and Nyssomyia intermedia were the most abundant species in peridomicile areas, whereas Martinsmyia minasensis and Lutzomyia cavernicola were the most abundant species among the different trail ecotopes. CONCLUSION: The different composition of the sand fly fauna observed in the peridomicile areas and in the trails during the study, reinforces the importance of sampled different areas in a phlebotomine fauna survey. The presence of Lutzomyia longipalpis and Ny. Intermedia most abundant in peridomicile can be important to Leishmania infantum and Leishmania braziliensis transmission in the Imbaúbas native village.
Assuntos
Psychodidae/fisiologia , Animais , Brasil , Clima , Conservação dos Recursos Naturais , Fenômenos Ecológicos e Ambientais , Ecossistema , Feminino , Humanos , Masculino , Grupos Populacionais , Psychodidae/classificação , Estações do AnoRESUMO
In the present study we surveyed the fauna of phlebotomine sand flies and small mammals in peridomestic areas from a Brazilian municipality where the American cutaneous leishmaniasis (ACL) is endemic. A total of 608 female phlebotomine sand flies were captured during nine months in 2009 and 2010. Seven different species were represented with 60% of them being Lutzomyia intermedia and Lu. whitmani, both incriminated vectors of ACL. Lu. longipalpis, a proven vector of visceral leishmaniasis (VL) was also captured at high proportion (12.8%). Genomic DNA analysis of 136 species-specific pools of female sand flies followed by molecular genotyping showed the presence of Leishmania infantum DNA in two pools of Lu. longipalpis. The same Leishmania species was found in one blood sample from Rattus norvegicus among 119 blood and tissue samples analysed. This is the first report of Le. infantum in R. norvegicus in the Americas and suggests a possible role for this rodent species in the zoonotic cycle of VL. Our study coincided with the reemergence of VL in Governador Valadares.
Assuntos
DNA/isolamento & purificação , Leishmania infantum/patogenicidade , Leishmaniose/sangue , Animais , Brasil , Humanos , Leishmania infantum/isolamento & purificação , Leishmaniose/parasitologia , Psychodidae/parasitologia , RatosRESUMO
This study was developed in the urban area of Governador Valadares, a reemerging focus of intense transmission of visceral leishmaniasis (VL) in Brazil, presenting 86 human cases of VL from 2008 to 2011. The disease prevailed in males (73.2%) with most patients between 0 and 9 years (44.1%) and a lethality rate of 16.2%. A canine survey was carried out on 16,529 domestic dogs in 35 districts in the area and it showed that 30.2% of them (4,992 dogs) were positive for VL by serum assays. Prevalence ratios for canine VL varied between 13.6% and 53.4%. The clinical exam of 343 seropositive dogs showed that 49.9% of them were considered symptomatic, with larger prevalence of canine VL being in short-furred animals (90%). The entomological survey was performed in eight districts, where 2,539 phlebotomines were captured, preferentially in the peridomicile (84.5%). Lutzomyia longipalpis was the predominant species (90%) suggesting its participation in the VL transmission in the area. The correlation between canine prevalence and L. longipalpis density was evaluated.