Evidence map of diagnosis, treatment, prognosis, prevention, and control in visceral leishmaniasis.

Objective: To develop an evidence map on visceral leishmaniasis prevention, control, diagnosis, treatment, and prognosis. Methods: Systematic reviews on visceral leishmaniasis were searched using MEDLINE/PubMed and Virtual Health Library. After selection, each included systematic review was assessed, characterized, and categorized by intervention type and by outcomes, according to the methodology offered by the PAHO/WHO Latin American and Caribbean Center on Health Sciences Information (BIREME). The methodological quality was assessed using the AMSTAR2 tool to determine the confidence level of the evidence obtained. Results: Among the prevention and control interventions, insecticide spraying, bednets, dog collars, and dog culling were the most assessed, emphasizing that insecticidal dog collars can reduce visceral leishmaniasis incidence in dogs. Regarding diagnosis, polymerase chain reaction (PCR), rK39 immunochromatographic test (rK39 ICT), and direct agglutination test (DAT) presented high sensitivity and specificity. As for treatment, pentavalent antimonials and amphotericin B were the most analyzed drugs and showed therapeutic success; however, serious adverse events can occur due to their use. The prognostic factors identified were anemia, edema, bleeding, jaundice, age, and HIV coinfection. Conclusions: The evidence map developed shows rK39 ICT and DAT as promising diagnostic alternatives and reinforces the efficacy of liposomal amphotericin B and pentavalent antimonials. Insecticide-impregnated dog collars appear as a promising measure for the control of visceral leishmaniasis, but there is also a need for future studies and reviews with higher methodological quality, especially on prevention and control interventions.

Epidemiological aspects of Chagas disease in the state of Piauí (Northeast Brazil) in the period 2010-2019.

Chagas disease (ChD), caused by the hemoflagellate protozoan Trypanosoma cruzi, is an important morbidity that affects approximately six million people in the American continent. T. cruzi parasites are mainly transmitted to human by the infected feces of blood-sucking triatomine insects. The persistent disease is endemic in many regions of South America, mostly affecting residents of rural areas. The aim of this study was to evaluate epidemiological aspects of ChD in the state of Pi-auí located in northeastern Brazil. This is an analytical cross-sectional study carried out from the collection of data of the Notifiable Diseases Information System (SINAN, in Portuguese, Sistema de Informações de Agravos de Notificação) of suspected and confirmed cases of acute ChD in the state of Piauí, in the period 2010-2019. Associations between T. cruzi positivity and the study variables were determined by the chi-square test or Fisher's exact test and were raised as prevalence ratios (PR) with 95% confidence interval. According to this survey, 517 suspected cases of acute ChD were reported in Piauí, with 70 cases (13.5%) confirmed. In 88.5% of confirmed cases, confirmation occurred by laboratory diagnosis. Most of the confirmed cases occurred in municipalities located in the semiarid region, with the municipality of São João do Piauí presenting the highest number of cases. Regarding sociodemographic data, females represent 55.7% of cases, people over 50 years of age (55.7%), being three cases in people up to 18 years of age, and less than 8 years of schooling (67.1%). 77.9% of confirmed cases had vector transmission as the probable form of infection. The data available in this study conclude that vectorial transmission of ChD in the state of Piauí remains active. This fact is corroborated by the number of notified and confirmed cases of acute ChD, requiring housing improvement programs and more effective epidemiological surveillance to control the transmission of the disease in the state.

Evidence map of diagnosis, treatment, prognosis, prevention, and control in visceral leishmaniasis / Mapa de evidencia sobre el diagnóstico, tratamiento, pronóstico, prevención y control de la leishmaniasis visceral / Mapa de evidências de diagnóstico, tratamento, prognóstico, prevenção e controle da leishmaniose visceral

ABSTRACT Objective. To develop an evidence map on visceral leishmaniasis prevention, control, diagnosis, treatment, and prognosis. Methods. Systematic reviews on visceral leishmaniasis were searched using MEDLINE/PubMed and Virtual Health Library. After selection, each included systematic review was assessed, characterized, and categorized by intervention type and by outcomes, according to the methodology offered by the PAHO/WHO Latin American and Caribbean Center on Health Sciences Information (BIREME). The methodological quality was assessed using the AMSTAR2 tool to determine the confidence level of the evidence obtained. Results. Among the prevention and control interventions, insecticide spraying, bednets, dog collars, and dog culling were the most assessed, emphasizing that insecticidal dog collars can reduce visceral leishmaniasis incidence in dogs. Regarding diagnosis, polymerase chain reaction (PCR), rK39 immunochromatographic test (rK39 ICT), and direct agglutination test (DAT) presented high sensitivity and specificity. As for treatment, pentavalent antimonials and amphotericin B were the most analyzed drugs and showed therapeutic success; however, serious adverse events can occur due to their use. The prognostic factors identified were anemia, edema, bleeding, jaundice, age, and HIV coinfection. Conclusions. The evidence map developed shows rK39 ICT and DAT as promising diagnostic alternatives and reinforces the efficacy of liposomal amphotericin B and pentavalent antimonials. Insecticide-impregnated dog collars appear as a promising measure for the control of visceral leishmaniasis, but there is also a need for future studies and reviews with higher methodological quality, especially on prevention and control interventions.

RESUMEN Objetivo. Elaborar un mapa de evidencia sobre la prevención, el control, el diagnóstico, el tratamiento y el pronóstico de la leishmaniasis visceral. Métodos. Se realizaron búsquedas de revisiones sistemáticas sobre la leishmaniasis visceral en MEDLINE/PubMed y la Biblioteca Virtual en Salud. Tras la selección, cada revisión sistemática incluida fue sometida a evaluación, caracterización y categorización según tipo de intervención y resultados, de acuerdo con la metodología ofrecida por el Centro Latinoamericano y del Caribe de Información en Ciencias de la Salud de la OPS/OMS (BIREME). La calidad metodológica se evaluó con la herramienta AMSTAR2 para determinar el nivel de confianza de la información obtenida. Resultados. Entre las intervenciones de prevención y control, las más evaluadas fueron la fumigación con insecticidas, los mosquiteros, los collares para perros y el sacrificio de perros y se hizo hincapié en que los collares insecticidas para perros pueden reducir la incidencia de leishmaniasis visceral en perros. En cuanto al diagnóstico, la reacción en cadena de la polimerasa (PCR, por su sigla en inglés), la prueba inmunocromatográfica rK39 (rK39 ICT) y la prueba de aglutinación directa (DAT, por su sigla en inglés) mostraron alta sensibilidad y especificidad. Con respecto al tratamiento, los fármacos más analizados que arrojaron éxito terapéutico fueron los antimoniales pentavalentes y la anfotericina B; sin embargo, su uso puede provocar efectos adversos graves. Los factores pronósticos que se identificaron fueron anemia, edema, sangrado, ictericia, edad y coinfección por el VIH. Conclusiones. El mapa de evidencia elaborado presenta la prueba inmunocromatográfica rK39 y la prueba de aglutinación directa como alternativas diagnósticas prometedoras, y consolida la eficacia de la anfotericina B liposomal y los antimoniales pentavalentes. Los collares de perro impregnados de insecticida parecen ser una medida prometedora para el control de la leishmaniasis visceral, si bien también son necesarios estudios y revisiones adicionales de mayor calidad metodológica, especialmente sobre intervenciones de prevención y control.

RESUMO Objetivo. Desenvolver um mapa de evidências de prevenção, controle, diagnóstico, tratamento e prognóstico da leishmaniose visceral. Métodos. Foram realizadas buscas por revisões sistemáticas sobre leishmaniose visceral no MEDLINE/PubMed e na Biblioteca Virtual em Saúde. Após a seleção, cada revisão sistemática incluída foi avaliada, caracterizada e classificada por tipo de intervenção e por desfechos, de acordo com a metodologia oferecida pelo Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde (BIREME) da OPAS/OMS. A qualidade metodológica foi avaliada utilizando a ferramenta AMSTAR2 para determinar o nível de confiança das evidências obtidas. Resultados. Entre as intervenções de prevenção e controle, pulverização com inseticida, mosquiteiros, coleiras para cães e abate de cães foram as mais frequentemente avaliadas, com destaque para as coleiras inseticidas na redução da incidência de leishmaniose visceral em cães. Quanto ao diagnóstico, a reação em cadeia da polimerase (PCR), o teste imunocromatográfico rK39 (rK39 ICT) e o teste de aglutinação direta (DAT, sigla em inglês para direct agglutination test) apresentaram alta sensibilidade e especificidade. Em relação ao tratamento, os antimoniais pentavalentes e a anfotericina B foram os medicamentos mais analisados e demonstraram sucesso terapêutico, embora seu uso possa resultar em eventos adversos graves. Os fatores prognósticos identificados foram anemia, edema, sangramento, icterícia, idade e coinfecção com HIV. Conclusões. O mapa de evidências desenvolvido mostra o rK39 ICT e o DAT como alternativas promissoras para o diagnóstico e reforça a eficácia da anfotericina B lipossomal e dos antimoniais pentavalentes. As coleiras impregnadas com inseticida aparecem como medida promissora para o controle da leishmaniose visceral, mas estudos e revisões futuras com mais qualidade metodológica, especialmente sobre intervenções de prevenção e controle, são necessários.

[Epidemiological profile and time trend in visceral leishmaniasis: Piauí, Brazil, 2008-2018]. / Perfil epidemiológico e tendência temporal da leishmaniose visceral: Piauí, Brasil, 2008 a 2018.

Visceral leishmaniasis (VL) or kala azar is one of the main neglected tropical diseases, of major importance due to the lethal nature of this zoonosis caused by protozoa of genus Leishmania. The study aimed to analyze the time trend in VL cases in the state of Piauí, Brazil, from 2008 to 2018, within the total period from 1971 to 2018. Data were obtained from the Brazilian Information System for Notificable Diseases (SINAN) and the Brazilian Mortality Information System (SIM). For burden of disease analysis, data were collected from the Institute for Health Metrics and Evaluation through the Global Burden of Diseases, Injuries, and Risk Factors (GBD Compare). Prais-Winsten regression analysis was used. A total of 2,374 cases were recorded with probable infection in the state of Piauí and 2,492 cases in residents of the state. The historical series analyzed, from 1971 to 2018, reaffirms the cyclical nature of the disease, based on the identification of epidemic peaks in 1983-1984, 1993-1994, 2003-2004, and 2013-2014. No significant alterations were identified in the trends in incidence, mortality, and case-fatality coefficients in the state. However, there was a significant increase in the incidence coefficient in the Chapada das Mangabeiras Development Territory, with an annual percent change of 17.5%, and a decrease in the Vale do Sambito Development Territory (-18.3%) and Vale do Rio Guaribas Development Territory (-8,1%). VL has a high burden of disease, measured by disability-adjusted life years, and is among the leading neglected tropical diseases in the state of Piauí. The study concludes by recommending the improvement of surveillance and control measures for this disease.

A leishmaniose visceral (LV) ou calazar é uma das principais doenças tropicais negligenciadas, de grande importância devido ao caráter letal desta zoonose causada por protozoários do gênero Leishmania. Objetivou-se analisar a tendência temporal dos casos de LV no Estado do Piauí, Brasil, de 2008 a 2018, inserindo-o dentro do período total de 1971 a 2018. Utilizaram-se dados do Sistema de Informação de Agravos de Notificação (SINAN) e do Sistema de Informações sobre Mortalidade (SIM). Para análise da carga da doença, foram coletados dados do Instituto de Métricas e Avaliação em Saúde através do estudo Carga Global de Doenças, Lesões e Fatores de Risco. Foi empregada a análise de regressão Prais-Winsten. Foram registrados 2.374 casos com provável local de infecção no Piauí e 2.492 casos em residentes do estado. A série histórica analisada, de 1971 a 2018, reafirma o caráter cíclico da doença, pela presença dos picos epidêmicos identificados em 1983 e 1984, 1993 e 1994, 2003 e 2004 e 2013 e 2014. Não foram identificadas alterações significativas na tendência dos coeficientes de incidência, mortalidade e letalidade no estado. No entanto, houve aumento significativo do coeficiente de incidência no Território de Desenvolvimento (TD) Chapada das Mangabeiras (variação percentual anual de 17,5%) e redução no TD Vale do Sambito (-18,3%) e TD Vale do Rio Guaribas (-8,1%). A LV tem a maior carga de doença medida em anos de vida ajustados por deficiência entre as doenças tropicais negligenciadas do estado. Recomenda-se o aprimoramento das medidas de vigilância e controle do agravo.

La leishmaniasis visceral (LV) o kala azar es una de las principales enfermedades tropicales desatendidas de gran importancia, debido al carácter letal de esta zoonosis causada por protozoos del género Leishmania. El objetivo fue analizar la tendencia temporal de los casos de LV en el estado de Piauí, Brasil, de 2008 a 2018, incluyéndola dentro del período total de 1971 a 2018. Se utilizaron datos del Sistema Brasileño de Información de Enfermedades de Notificación (SINAN) y del Sistema de Información sobre Mortalidad (SIM). Para el análisis de la carga de la enfermedad, se recogieron datos del Instituto de Métricas y Evaluación en Salud, a través del estudio Carga Global de Enfermedades, Lesiones y Factores de Riesgo (GBD Compare). Se empleó el análisis de regresión Prais-Winsten. Se registraron 2.374 casos con probable lugar de infección en Piauí y 2492 casos en residentes del estado. La serie histórica analizada, de 1971-2018, reafirma el carácter cíclico de la enfermedad por la presencia de los picos epidémicos, identificados en 1983 y 1984, 1993 y 1994, 2003 y 2004 y 2013 y 2014. No se identificaron alteraciones significativas en la tendencia de los coeficientes de incidencia, mortalidad y letalidad en el estado. No obstante, hubo un aumento significativo del coeficiente de incidencia en el Territorio de Desarrollo (TD) Chapada das Mangabeiras (variación del porcentaje anual de 17,5%) y reducción en el TD Vale do Sambito (-18,3%) y TD Vale do Rio Guaribas (-8,1%). La LV tiene una mayor carga de enfermedad medida en años de vida ajustados por deficiencia entre las enfermedades tropicales olvidadas del estado. Se recomienda el perfeccionamiento de las medidas de vigilancia y control de la enfermedad.

Checklist and phenetics studies of nymphs of two species of triatomines: Triatoma lenti Sherlock & Serafim, 1967 and Triatoma sherlocki Papa, Jurberg, Carcavallo, Cerqueira, Barata, 2002 (Hemiptera: Reduviidae: Triatominae).

INTRODUCTION: Triatoma lenti and Triatoma sherlocki are endemic species of the State of Bahia, located in northeastern Brazil, where they have records of domiciliation in the human environment. In view of the epidemiological aspect and taxonomic importance of these species for the systematics of the Triatoma genus, a study was carried out with nymphs of all five instars. METHODS: An extensive review of studies on nymphs from the subfamily Triatominae is presented. Morphology was studied using a scanning electron microscope and morphometric analyses. RESULTS: The morphological study allowed us to characterize and discriminate species by means of scanning electron microscope of the last abdominal segment. In addition, the results show morphometric variability, with the total size of the head that best discriminates the species. CONCLUSIONS: Studies on nymphs are fundamental to the ecosystem; however, the literature on the immature forms of certain groups is scarce, difficult to use, or nonexistent. Therefore, this study includes morphological and morphometric data of the nymphal instars of T. lenti and T. sherlocki, corroborating the specific taxonomy of these species.

Seroprevalence of Chagas disease in rural communities at Campinas do Piauí city, Brazil.

OBJECTIVES: This manuscript aimed to evaluate the seroprevalence of Chagas's disease in the population of rural communities at Campinas do Piauí city, State of Piauí, Brazil. METHODS: The techniques of the indirect immunofluorescence reaction and enzyme-linked immunosorbent assay were used to detect reagent samples for Chagas disease and estimate its prevalence in the rural population. Blood samples were collected on filter paper through digital and venipuncture. Blood samples with reactive or indeterminate results were re-evaluated and subjected to the test by ELISA. RESULTS: In total, 763 blood samples were analysed from 161 residences of 18 rural communities, collected in residents aged between 2 and 92 years. In the indirect immunofluorescence reaction technique, 44 (5.8%) of the results were positive, being 40 (5.2%) confirmed by the enzyme-linked immunosorbent assay. Among the communities surveyed, we observed reactive cases in 15 of them, these cases being distributed, according to the age group, as follows: 1 case from 0 to 10 years; 13 cases from 11 to 60 years old; and 30 cases over 61 years. CONCLUSION: The results indicate that Chagas's disease remains with active transmission in the Campinas do Piaui city according to the occurrence of a case in a resident under 10 years of age. The region is endemic for Chagas's disease, as observed by the high prevalence of positive cases.

OBJECTIFS: Ce manuscrit visait à évaluer la séroprévalence de la maladie de Chagas dans la population des communautés rurales de la ville de Campinas do Piauí, état de Piauí, au Brésil. MÉTHODES: Les techniques de la réaction d'immunofluorescence indirecte et ELISA ont été utilisées pour détecter des échantillons réagissant pour la maladie de Chagas et estimer sa prévalence dans la population rurale. Des échantillons de sang ont été collectés sur papier filtre par ponction digitale et veineuse. Les échantillons de sang avec des résultats positifs ou indéterminés ont été réévalués et soumis au test ELISA. RÉSULTATS: Au total, 763 échantillons de sang ont été analysés dans 161 résidences de 18 communautés rurales, prélevés chez des résidents âgés de 2 à 92 ans. Dans la technique de la réaction d'immunofluorescence indirecte, 44 (5,8%) des résultats étaient positifs, dont 40 (5,2%) confirmés par le test ELISA. Parmi les communautés enquêtées, nous avons observé des cas réactifs dans 15 d'entre eux, ces cas se répartissant, selon la tranche d'âge, comme suit: 1 cas chez les 0 à 10 ans, 13 cas chez les 11 à 60 ans, 30 cas chez des plus de 61 ans. CONCLUSION: Les résultats indiquent que la maladie de Chagas maintient une transmission active dans la ville de Campinas do Piauí avec la survenue d'un cas chez un résident de moins de 10 ans. La région est endémique pour la maladie de Chagas, comme en témoigne la forte prévalence des cas positifs.

Perfil epidemiológico e tendência temporal da leishmaniose visceral: Piauí, Brasil, 2008 a 2018 / Epidemiological profile and time trend in visceral leishmaniasis: Piauí, Brazil, 2008-2018 / Perfil epidemiológico y tendencia temporal de la leishmaniasis visceral: Piauí, Brasil, 2008 a 2018

A leishmaniose visceral (LV) ou calazar é uma das principais doenças tropicais negligenciadas, de grande importância devido ao caráter letal desta zoonose causada por protozoários do gênero Leishmania. Objetivou-se analisar a tendência temporal dos casos de LV no Estado do Piauí, Brasil, de 2008 a 2018, inserindo-o dentro do período total de 1971 a 2018. Utilizaram-se dados do Sistema de Informação de Agravos de Notificação (SINAN) e do Sistema de Informações sobre Mortalidade (SIM). Para análise da carga da doença, foram coletados dados do Instituto de Métricas e Avaliação em Saúde através do estudo Carga Global de Doenças, Lesões e Fatores de Risco. Foi empregada a análise de regressão Prais-Winsten. Foram registrados 2.374 casos com provável local de infecção no Piauí e 2.492 casos em residentes do estado. A série histórica analisada, de 1971 a 2018, reafirma o caráter cíclico da doença, pela presença dos picos epidêmicos identificados em 1983 e 1984, 1993 e 1994, 2003 e 2004 e 2013 e 2014. Não foram identificadas alterações significativas na tendência dos coeficientes de incidência, mortalidade e letalidade no estado. No entanto, houve aumento significativo do coeficiente de incidência no Território de Desenvolvimento (TD) Chapada das Mangabeiras (variação percentual anual de 17,5%) e redução no TD Vale do Sambito (-18,3%) e TD Vale do Rio Guaribas (-8,1%). A LV tem a maior carga de doença medida em anos de vida ajustados por deficiência entre as doenças tropicais negligenciadas do estado. Recomenda-se o aprimoramento das medidas de vigilância e controle do agravo.

Visceral leishmaniasis (VL) or kala azar is one of the main neglected tropical diseases, of major importance due to the lethal nature of this zoonosis caused by protozoa of genus Leishmania. The study aimed to analyze the time trend in VL cases in the state of Piauí, Brazil, from 2008 to 2018, within the total period from 1971 to 2018. Data were obtained from the Brazilian Information System for Notificable Diseases (SINAN) and the Brazilian Mortality Information System (SIM). For burden of disease analysis, data were collected from the Institute for Health Metrics and Evaluation through the Global Burden of Diseases, Injuries, and Risk Factors (GBD Compare). Prais-Winsten regression analysis was used. A total of 2,374 cases were recorded with probable infection in the state of Piauí and 2,492 cases in residents of the state. The historical series analyzed, from 1971 to 2018, reaffirms the cyclical nature of the disease, based on the identification of epidemic peaks in 1983-1984, 1993-1994, 2003-2004, and 2013-2014. No significant alterations were identified in the trends in incidence, mortality, and case-fatality coefficients in the state. However, there was a significant increase in the incidence coefficient in the Chapada das Mangabeiras Development Territory, with an annual percent change of 17.5%, and a decrease in the Vale do Sambito Development Territory (-18.3%) and Vale do Rio Guaribas Development Territory (-8,1%). VL has a high burden of disease, measured by disability-adjusted life years, and is among the leading neglected tropical diseases in the state of Piauí. The study concludes by recommending the improvement of surveillance and control measures for this disease.

La leishmaniasis visceral (LV) o kala azar es una de las principales enfermedades tropicales desatendidas de gran importancia, debido al carácter letal de esta zoonosis causada por protozoos del género Leishmania. El objetivo fue analizar la tendencia temporal de los casos de LV en el estado de Piauí, Brasil, de 2008 a 2018, incluyéndola dentro del período total de 1971 a 2018. Se utilizaron datos del Sistema Brasileño de Información de Enfermedades de Notificación (SINAN) y del Sistema de Información sobre Mortalidad (SIM). Para el análisis de la carga de la enfermedad, se recogieron datos del Instituto de Métricas y Evaluación en Salud, a través del estudio Carga Global de Enfermedades, Lesiones y Factores de Riesgo (GBD Compare). Se empleó el análisis de regresión Prais-Winsten. Se registraron 2.374 casos con probable lugar de infección en Piauí y 2492 casos en residentes del estado. La serie histórica analizada, de 1971-2018, reafirma el carácter cíclico de la enfermedad por la presencia de los picos epidémicos, identificados en 1983 y 1984, 1993 y 1994, 2003 y 2004 y 2013 y 2014. No se identificaron alteraciones significativas en la tendencia de los coeficientes de incidencia, mortalidad y letalidad en el estado. No obstante, hubo un aumento significativo del coeficiente de incidencia en el Territorio de Desarrollo (TD) Chapada das Mangabeiras (variación del porcentaje anual de 17,5%) y reducción en el TD Vale do Sambito (-18,3%) y TD Vale do Rio Guaribas (-8,1%). La LV tiene una mayor carga de enfermedad medida en años de vida ajustados por deficiencia entre las enfermedades tropicales olvidadas del estado. Se recomienda el perfeccionamiento de las medidas de vigilancia y control de la enfermedad.

Phenotypic and genetic variation of Triatoma costalimai (Hemiptera: Reduviidae)

Abstract INTRODUCTION: We aimed to study intraspecific variation in Triatoma costalimai, a potential vector of Chagas disease present in Brazil and Bolivia. METHODS: We analyzed phenotypic (connexivum color patterns, wing morphometrics) and genetic variation (16S mtDNA) of three Brazilian T. costalimai populations. We compared 16S sequences with those of putative Bolivian T. costalimai and its sister species, T. jatai. RESULTS: Brazilian populations had different connexivum color patterns and forewing shapes. A 16S mtDNA haplotype network showed a clear separation of Brazilian T. costalimai from both T. jatai and Bolivian T. costalimai. CONCLUSIONS: We report considerable variability in T. costalimai populations.

Phenotypic and genetic variation of Triatoma costalimai (Hemiptera: Reduviidae).

INTRODUCTION: We aimed to study intraspecific variation in Triatoma costalimai, a potential vector of Chagas disease present in Brazil and Bolivia. METHODS: We analyzed phenotypic (connexivum color patterns, wing morphometrics) and genetic variation (16S mtDNA) of three Brazilian T. costalimai populations. We compared 16S sequences with those of putative Bolivian T. costalimai and its sister species, T. jatai. RESULTS: Brazilian populations had different connexivum color patterns and forewing shapes. A 16S mtDNA haplotype network showed a clear separation of Brazilian T. costalimai from both T. jatai and Bolivian T. costalimai. CONCLUSIONS: We report considerable variability in T. costalimai populations.

Triatoma brasiliensis Neiva, 1911 and Triatoma pseudomaculata Corrêa and Espínola, 1964 (Hemiptera, Reduviidae, Triatominae) in rural communities in Northeast Brazil.

Chagas disease is an important endemic morbidity in Latin America affecting millions of people in the American continent. It is caused by the protozoan Trypanosoma cruzi, and transmitted through the feces of the insect vector belonging to the subfamily Triatominae. The present conducted an entomological survey of triatomines and analyzed entomological indicators, such as the rate of infestation, colonization, triatomine density and natural infection in rural communities in the municipality of Campinas do Piaui, Piaui State, in the Northeast region of Brazil. Data on the search of triatomines performed in 167 domiciliary units (DUs), harvested during the period of February to July 2019, in 12 rural communities were analyzed. The capture of triatomines occurred in all studied communities, being 76 the number of positive DUs, of the 167 surveyed, presenting a global rate of infestation of 45.51%. Two triatomines species were collected: Triatoma brasiliensis (98.49%) and T. pseudomaculata (1.51%), the first was found in the domiciliary and peridomiciliary areas, while the second was captured only in peridomiciliary areas. The index of colonization was 17.1%. Natural infection was observed only in 5.44% of T. brasiliensis samples. The entomological survey was conducted in rural communities, showingthe risk of transmission of Chagas disease to the local population, requiring continuous entomological surveillance and vector control.

Triatoma brasiliensis species complex: characterization of the external female genitalia.

The Triatoma brasiliensis complex is composed of six species (Triatoma bahiensis, T. juazerensis, T. lenti, T. melanica, T. petrocchiae, and T. sherlocki) and two subspecies (T. brasiliensis brasiliensis and T. b. macromelasoma). Phylogenetic studies have shown that it is a monophyletic group, but the morphological relationships among the members can be better understood. We applied a tool of high resolution based on morphology to identify details that characterize the female genitals for each member of this group. The external genital structures of five to fifteen females of each taxon were analyzed. Insects had their abdomen transversely cut to separate the last abdominal segments, and representative illustrations obtained via scanning electron microscopy (SEM) are shown. Observations were performed in the dorsal and the ventral views. The morphological characterization of female external genitalia allowed a differentiation of each species/subspecies. The subspecies T. b. brasiliensis and T. b. macromelasoma were the most similar. On the other hand, dorsal view of structures evidenced some unique characteristics for T. petrocchiae and T. sherlocki. Regarding these structures for T. petrocchiae, the differentiation was in accordance with molecular studies, since this species exhibits the highest genetic distances in relation to other species of T. brasiliensis complex.

Differentiation of Rhodnius neglectus and Rhodnius prolixus (Hemiptera: Reduviidae: Triatominae) by multiple parameters.

INTRODUCTION: The genus Rhodnius in the subfamily Triatominae comprises 20 species, which can transmit Trypanosoma cruzi and Trypanosoma rangeli. Due to the development of molecular techniques, Triatominae species can now be characterized by mitochondrial and nuclear markers, making it possible to verify and/or correct the existing data on these species. The results achieved in this study provide a more detailed and accurate differentiation of the Rhodnius species, helping the establishment of a more appropriate classification. METHODS: Data collection was performed by DNA analysis, morphological and morphometric studies to distinguish four populations of R. neglectus and four of R. prolixus. Phylogenetic data were compared to morphological and morphometric data. RESULTS: The analysis of Cytb fragments suggests that the four colonies designated to Rhodnius neglectus as well as those of R. prolixus were correctly identified. CONCLUSIONS: The morphological characters observed in the specimens of the colonies originally identified as R. prolixus and R. neglectus, such as the presence or absence of collar in the eggs, the patterns of the median process of the pygophore, and anterolateral angle, are consistent with the species. Geometric morphometrics also show an intraspecific variability in R. prolixus.

Differentiation of Rhodnius neglectus and Rhodnius prolixus (Hemiptera: Reduviidae: Triatominae) by multiple parameters

Abstract Introduction: The genus Rhodnius in the subfamily Triatominae comprises 20 species, which can transmit Trypanosoma cruzi and Trypanosoma rangeli. Due to the development of molecular techniques, Triatominae species can now be characterized by mitochondrial and nuclear markers, making it possible to verify and/or correct the existing data on these species. The results achieved in this study provide a more detailed and accurate differentiation of the Rhodnius species, helping the establishment of a more appropriate classification. Methods: Data collection was performed by DNA analysis, morphological and morphometric studies to distinguish four populations of R. neglectus and four of R. prolixus. Phylogenetic data were compared to morphological and morphometric data. Results: The analysis of Cytb fragments suggests that the four colonies designated to Rhodnius neglectus as well as those of R. prolixus were correctly identified. Conclusions: The morphological characters observed in the specimens of the colonies originally identified as R. prolixus and R. neglectus, such as the presence or absence of collar in the eggs, the patterns of the median process of the pygophore, and anterolateral angle, are consistent with the species. Geometric morphometrics also show an intraspecific variability in R. prolixus.

Genetic Structure of Brazilian Populations of Triatoma sordida (Stål, 1859) (Hemiptera, Triatominae) by Means of Chromosomal Markers.

Triatoma sordida is among the main Brazilian species considered as Chagas disease vectors. The genetic studies are directed mainly to phylogenetic questions because this species possibly have suffered cryptic speciation. Furthermore, there are few studies that analyzed the structure and genetic variability of specimens from Brazil and that showed low genetic diversity and strong genetic structuring of the population samples. Therefore, because of great epidemiological importance of T. sordida and mainly the restriction of genetic characterization of this vector only for populations of Minas Gerais state, this article performs a genetic analysis of the T. sordida from seven different Brazilian states (representing different biomes), by means of cytogenetic markers. All analyzed specimens presents the same cytogenetic characteristics: early meiotic prophase with several heterochromatic bodies dispersed in the nucleus (CG-rich), being one of them formed by the associated sex chromosomes surrounded by some autosomal heterochromatic regions, meiotic metaphase with most autosomal pairs exhibiting a C-heterochromatic block in one chromosomal end (CG-rich), Y sex chromosome fully heterochromatin (AT-rich), and X chromosome may present a small C-block (CG-rich). These results are important because the chromosomal markers enable to confirm and expand the low genetic diversity for all Brazilian states occupied by T. sordida, suggesting that all Brazilian populations were originated from a small ancestral population and possibly dispersed to other biomes by founder effect. In addition, we suggest that T. sordida from Brazil are not suffering cryptic speciation and we confirm the classification of all Brazilian examples as T. sordida sensu stricto.

Hybrid Collapse Confirms the Specific Status of Triatoma bahiensis Sherlock and Serafim, 1967 (Hemiptera, Triatominae), an Endemic Species in Brazil.

Six to seven million people worldwide are estimated to be infected with Trypanosoma cruzi, the etiologic agent of Chagas disease transmitted mainly by triatomines. Triatoma bahiensis was recently collected in the Brazilian state of Bahia and revalidated using different approaches. The main criterion used to define a "good" biological species is reproductive isolation, so we evaluated the cytogenetics of first-generation (F1) hybrids resulting from the experimental cross between T. bahiensis females and Triatoma lenti males to possibly characterize the postzygotic isolation associated with the hybrid breakdown. All cells analyzed presented a karyotype of 2n = 22 and a pair of univalent autosomes. This chromosome behavior represents hybrid collapse and underscores the specific status of T. bahiensis. Thus, we have characterized the presence of the hybrid collapse phenomenon in an experimental cross, and we confirm the specific status of T. bahiensis, thus contributing to the Triatominae taxonomy.

Morphology of the spermathecae of twelve species of Triatominae (Hemiptera, Reduviidae) vectors of Chagas disease.

Trypanosoma cruzi, the etiological agent of Chagas disease, is transmitted by triatomines that have been described in a large number of studies. Most of those studies are related to external morphology and taxonomy, but some biochemical, genetic and physiological studies have also been published. There are a few publications in the literature about the internal organs of Triatominae, for instance the spermathecae, which are responsible for storing and maintaining the viability of the spermatozoids until the fertilization of the oocytes. This work aims to study the spermathecae of twelve species of triatomines obtained from the Triatominae Insectarium of the Faculty of Pharmaceutical Sciences, UNESP, Araraquara, using optical microscopy and scanning electron microscopy. The spermathecae of the twelve species studied showed three morphological patterns: a) P. herreri sn, P. lignarius, P. megistus, Triatoma brasiliensis, T. juazeirensis, T. sherlocki and T. tibiamaculata have spermathecae with a thin initial portion and an oval-shaped final portion; b) R. montenegrensis, R. nasutus, R. neglectus, R. pictipes and R. prolixus have tubular and winding spermathecae; c) T. infestans has oval spermathecae. In addition to the three morphological patterns, it was noted that each of the twelve species has particular features that differentiate them.

A new species of Rhodnius from Brazil (Hemiptera, Reduviidae, Triatominae).

A colony was formed from eggs of a Rhodnius sp. female collected in Taquarussu, Mato Grosso do Sul, Brazil, and its specimens were used to describe R. taquarussuensissp. n. This species is similar to R. neglectus, but distinct characters were observed on the head, thorax, abdomen, female external genitalia and male genitalia. Chromosomal differences between the two species were also established.

Automated identification of insect vectors of Chagas disease in Brazil and Mexico: the Virtual Vector Lab.

Identification of arthropods important in disease transmission is a crucial, yet difficult, task that can demand considerable training and experience. An important case in point is that of the 150+ species of Triatominae, vectors of Trypanosoma cruzi, causative agent of Chagas disease across the Americas. We present a fully automated system that is able to identify triatomine bugs from Mexico and Brazil with an accuracy consistently above 80%, and with considerable potential for further improvement. The system processes digital photographs from a photo apparatus into landmarks, and uses ratios of measurements among those landmarks, as well as (in a preliminary exploration) two measurements that approximate aspects of coloration, as the basis for classification. This project has thus produced a working prototype that achieves reasonably robust correct identification rates, although many more developments can and will be added, and-more broadly-the project illustrates the value of multidisciplinary collaborations in resolving difficult and complex challenges.

Revalidation of Triatoma bahiensis Sherlock & Serafim, 1967 (Hemiptera: Reduviidae) and phylogeny of the T. brasiliensis species complex.

Triatoma bahiensis Sherlock & Serafim, 1967, T. lenti Sherlock & Serafim, 1967, and T. pessoai Sherlock & Serafim, 1967 were described based on material collected in the Brazilian state of Bahia. These species were later included in the T. brasiliensis complex based on their geographic distribution. Triatoma bahiensis and T. pessoai were subsequently synonymized with T. lenti. However, the phylogenetic position of T. lenti within the T. brasiliensis complex has remained doubtful. This study aims to assess the taxonomic status of T. bahiensis and to infer the phylogenetic relationships between T. lenti, T. bahiensis and the other members of the T. brasiliensis species complex. The identities of the species in concern were confirmed by comparisons with high resolution photos of the respective type materials; lectotypes are designated for T. pessoai and T. bahiensis. Morphological, morphometric, molecular, and cytogenetic approaches as well as experimental crosses were used. The low viability of experimental crosses combined with morphological and morphometric data allow the differentiation of T. bahiensis and T. lenti. Pairwise cyt b sequence divergence between T. lenti and T. bahiensis was 2.5%. Cytogenetic and molecular analyses grouped T. lenti and T. bahiensis as members of the T. brasiliensis complex. These results revalidate the specific status of T. bahiensis.

Triatominae survey (Hemiptera: Reduviidae: Triatominae) in the south-central region of the state of Bahia, Brazil between 2008 and 2013.

Triatomine surveillance in rural areas, artificial ecotypes, and natural ecotopes of the cities of Caturama, Ibipitanga, Macaúbas, and Seabra in the south-central region of the Brazilian state of Bahia was carried out between 2008 and 2013. Natural infection by Trypanosoma cruzi was evaluated in the specimens collected to monitor vectors of Chagas disease. A total of 1,357 specimens were collected, and four species were identified: Triatoma sordida (83%), Triatoma lenti (16.4%), Triatoma pseudomaculata (0.5%), and Panstrongylus geniculatus (0.1%). Triatoma sordida was found in four cities, only 0.7% in intradomiciliary environments. Triatoma lenti was found only in Macaúbas; 8.5% were found in intradomiciliary environments, 88.3% in peridomiciliary environments, and 3.1% in sylvatic environments. Natural infection by T. cruzi was 0.5% for T. sordida and 3.1% T. lenti. All of these cases were found in peridomiciliary environments of Macaúbas. As the results show, triatomines were found in intradomiciliary environments in three cities that were surveyed in the south-central region of the state of Bahia. Thus, an epidemiologic survey should be performed to avoid the risk of transmission to the population.