Circulation of Trypanosoma cruzi in triatomines and Didelphis sp. in urban areas: Transmission risk assessment in the Metropolitan Region.

The presence of Trypanosoma cruzi vectors in urban areas has been frequent, with colonization of homes and associated with reservoir animals that increase risk to humans, with simultaneous circulation of vectors and T. cruzi. The study aimed to describe the circulation of triatomines and T. cruzi in the Metropolitan Region of São Paulo, as well as evaluate risk situations. For analysis purposes, the triatomine notification information from January 2016 to July 2023 was used. While for Didelphis sp. collection with the aid of traps, notification information used was from 2019 to 2023. Information about triatomines came from spontaneous demand by the population and notification services were carried out by state field teams following defined protocols. 202 notifications were received with the capture of 448 triatomines. The positivity for T. cruzi observed was 60.5%. Regarding Didelphis sp., 416 animals were collected, 5.3% of which were positive for T. cruzi. There was overlapping areas of presence of infected triatomines and Didelphis sp., whose Discrete Typing Unit (DTU) was T. cruzi I. This work indicates the presence of infected vectors in urban areas, and the presence of a wild cycle of T. cruzi in didelphiids, reaffirming the need for and importance of vector surveillance work, through actions that can prevent the transmission of Chagas disease.

Avaliação externa da qualidade da identificação entomológica de triatomíneos realizada na Rede de Laboratórios Públicos em Pernambuco, 2017 / Evaluación externa de la calidad en la identificación entomológica de triatominos realizada en la red de laboratorios públicos en Pernambuco, Brasil, 2017 / External quality assessment of entomological identification of triatomines carried out in the Pernambuco Public Health Laboratory network, Brazil, 2017

Objetivo: Avaliar a qualidade da identificação de triatomíneos na rede de laboratórios do estado de Pernambuco, Brasil. Métodos: Os nove laboratórios participantes receberam material de apoio com as chaves dicotômicas e um painel composto por sete insetos triatomíneos conhecidos no estado, para identificação da situação do espécime no recebimento (estrutura completa ou danificada), espécie e sexo. Resultados: Nove laboratórios de 12 aderiram ao estudo. A proporção de acerto para identificação do sexo foi de 56/63, e para espécie, 45/63, não apresentando relação direta com a ocorrência de danos nas estruturas morfológicas durante o transporte dos insetos. Para Panstrongylus megistus, houve acerto em todos os espécimes (9/9), enquanto para espécies do gênero Rhodnius a proporção foi menor (3/9). Conclusão: Apesar do bom desempenho na identificação entomológica, as fragilidades observadas poderão orientar ações para melhoria na rede de laboratórios e serão essenciais para os programas de controle vetorial da doença de Chagas.

Objetivo: Evaluar la calidad de la identificación de triatominos en la red de laboratorios del estado de Pernambuco, Brasil. Métodos: Los nueve laboratorios participantes recibieron material de apoyo con claves dicotómicas y un panel conformado por siete insectos triatominos conocidas en el estado, para identificar la situación del espécimen al recibirlo (estructura completa o dañada), especie y sexo. Resultados: La adherencia al laboratorio fue del 9/12. La proporción de aciertos para la identificación del sexo fue del 56/63, y para las especies 45/63, no mostraron relación directa con la ocurrencia de daños en las estructuras morfológicas durante el transporte de insectos. Solo Panstrongylus megistus logró el 9/9 de precisión, mientras que para las especies del género Rhodnius fue el más pequeño (3/9). Conclusión: A pesar del buen desempeño en identificación entomológica, la evaluación indicó debilidades que permitirán implementar acciones correctivas para mejorar la red de laboratorios, esenciales para los programas de control vectorial de la enfermedad de Chagas.

Objective: To assess the quality of triatomine identification in the laboratory network of the state of Pernambuco, Brazil. Methods: The participating laboratories received support material with dichotomous keys and a panel made up of seven triatomine insects known in the Pernambuco, in order to identify specimen status on receipt (intact or damaged structure), as well as species and sex. Results: Nine out of 12 laboratories took part of the study. The proportion of correct answers was 56/63 for sex identification, and 45/63, for species. The answers did not present a direct relationship with occurrence of damage to morphological structures during insect transportation. Panstrongylus megistus identification was correct for all specimens (9/9 laboratories), while correct identification of species of the Rhodnius genus was the lowest (3/9 laboratories). Conclusion: Despite the good performance in entomological identification, the weaknesses observed may guide improvements in the laboratory network and will be essential for Chagas disease vector control programs.

Chagas Disease: Epidemiology and Barriers to Treatment.

Chronic human infection by the protozoan parasite Trypanosoma cruzi, known as Chagas disease, results in heart failure and death in 20%-30% of affected individuals. Recognition and treatment of the infection are difficult. Disease control requires elimination of the vector, the reduviid bug, that infests housing of poor quality in endemic areas. In South America, control has largely succeeded in the Southern Cone countries-Argentina, Chile, Uruguay, southern Brazil and São Paulo, and Paraguay-but lags severely in the Northern Triangle (Central American) countries: El Salvador, Honduras, and Guatemala. Surges in poverty and violence in Central America have increased immigration of persons at risk for Chagas disease to the United States, and immigrants to the United States with Chagas disease face multiple barriers to obtaining effective care. These include issues with financing and payment for health care, limited effectiveness of screening and diagnosis, limited effectiveness of available treatment, and lack of provider awareness, public health education, and research. Each of these barriers presents a unique public health challenge.

Multi-criteria decision analysis and spatial statistic: an approach to determining human vulnerability to vector transmission of Trypanosoma cruzi

BACKGROUND Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is a neglected human disease. It is endemic to the Americas and is estimated to have an economic impact, including lost productivity and disability, of 7 billion dollars per year on average. OBJECTIVES To assess vulnerability to vector-borne transmission of T. cruzi in domiciliary environments within an area undergoing domiciliary vector interruption of T. cruzi in Colombia. METHODS Multi-criteria decision analysis [preference ranking method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive assistance (GAIA) methods] and spatial statistics were performed on data from a socio-environmental questionnaire and an entomological survey. In the construction of multi-criteria descriptors, decision-making processes and indicators of five determinants of the CD vector pathway were summarily defined, including: (1) house indicator (HI); (2) triatominae indicator (TI); (3) host/reservoir indicator (Ho/RoI); (4) ecotope indicator (EI); and (5) socio-cultural indicator (S-CI). FINDINGS Determination of vulnerability to CD is mostly influenced by TI, with 44.96% of the total weight in the model, while the lowest contribution was from S-CI, with 7.15%. The five indicators comprise 17 indices, and include 78 of the original 104 priority criteria and variables. The PROMETHEE and GAIA methods proved very efficient for prioritisation and quantitative categorisation of socio-environmental determinants and for better determining which criteria should be considered for interrupting the man-T. cruzi-vector relationship in endemic areas of the Americas. Through the analysis of spatial autocorrelation it is clear that there is a spatial dependence in establishing categories of vulnerability, therefore, the effect of neighbors' setting (border areas) on local values should be incorporated into disease management for establishing programs of surveillance and control of CD via vector. CONCLUSIONS The study model proposed here is flexible and can be adapted to various eco-epidemiological profiles and is suitable for focusing anti-T. cruzi serological surveillance programs in vulnerable human populations.

Multi-criteria decision analysis and spatial statistic: an approach to determining human vulnerability to vector transmission of Trypanosoma cruzi.

BACKGROUND: Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is a neglected human disease. It is endemic to the Americas and is estimated to have an economic impact, including lost productivity and disability, of 7 billion dollars per year on average. OBJECTIVES: To assess vulnerability to vector-borne transmission of T. cruzi in domiciliary environments within an area undergoing domiciliary vector interruption of T. cruzi in Colombia. METHODS: Multi-criteria decision analysis [preference ranking method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive assistance (GAIA) methods] and spatial statistics were performed on data from a socio-environmental questionnaire and an entomological survey. In the construction of multi-criteria descriptors, decision-making processes and indicators of five determinants of the CD vector pathway were summarily defined, including: (1) house indicator (HI); (2) triatominae indicator (TI); (3) host/reservoir indicator (Ho/RoI); (4) ecotope indicator (EI); and (5) socio-cultural indicator (S-CI). FINDINGS: Determination of vulnerability to CD is mostly influenced by TI, with 44.96% of the total weight in the model, while the lowest contribution was from S-CI, with 7.15%. The five indicators comprise 17 indices, and include 78 of the original 104 priority criteria and variables. The PROMETHEE and GAIA methods proved very efficient for prioritisation and quantitative categorisation of socio-environmental determinants and for better determining which criteria should be considered for interrupting the man-T. cruzi-vector relationship in endemic areas of the Americas. Through the analysis of spatial autocorrelation it is clear that there is a spatial dependence in establishing categories of vulnerability, therefore, the effect of neighbors' setting (border areas) on local values should be incorporated into disease management for establishing programs of surveillance and control of CD via vector. CONCLUSIONS: The study model proposed here is flexible and can be adapted to various eco-epidemiological profiles and is suitable for focusing anti-T. cruzi serological surveillance programs in vulnerable human populations.

Community participation and domiciliary occurrence of infected Meccus longipennis in two Mexican villages in Jalisco state.

The entomological features of Chagas disease in two western Mexican villages were analyzed through triatomines collection by the inhabitants and active research in the peridomicile. The inhabitant collections have the following comparable characteristics: 1) Meccus longipennis was the dominant species (> 91%), 2) around 43% of the insects were collected indoors, 3) about 70% of triatomines were adults, 4) cumulated rates of infestation of the dwellings reached 40-50%, 5) the triatomine infection rate by Trypanosoma cruzi was > 50%, and 6) the indoor triatomines frequently feed on humans (range 38.5-56.2%). However, the collection was twice as abundant in the first village and the peridomicile infestation, evaluated by the active collection, reached up to 60% and only 4.9% in the other village. Furthermore, females predominated in the first village, whereas males in the other. The current results allow discussing the course of action to prevent Chagas disease in this region.

[Evaluation of knowledge and practices related to Chagas disease and its vectors among adults and children in an endemic region in Minas Gerais State, Brazil]. / Avaliação de conhecimentos e práticas que adultos e crianças têm acerca da doença de Chagas e seus vetores em região endêmica de Minas Gerais, Brasil.

Despite the success of the Chagas Disease Control Program (PCCD) in Brazil, some endemic areas have experienced difficulty in maintaining the program's activities, especially after the health system's decentralization, since the sustainability of control measures for Chagas disease and vectors is known to depend on information and community participation. This study aimed to analyze knowledge and practices related to vectors and Chagas disease in Bambuí, Minas Gerais State, Brasil. The population's knowledge was tested with a questionnaire, accompanied by six illustrations of triatomine bugs for identification. Both adults and primary and secondary schoolchildren in rural areas of the county participated in the research. The Bambuí population showed good overall knowledge on triatomines and Chagas disease in both groups (adults and children), although the concepts were limited to preventing the insect vector from invading houses. The results emphasize the importance of educational campaigns in the context of the program as a fundamental component of community participation in Chagas disease vector control.

Avaliação de conhecimentos e práticas que adultos e crianças têm acerca da doença de Chagas e seus vetores em região endêmica de Minas Gerais, Brasil / Evaluation of knowledge and practices related to Chagas disease and its vectors among adults and children in an endemic region in Minas Gerais State, Brazil

Apesar do sucesso no Programa de Controle da Doença de Chagas (PCDCh) no Brasil, alguns locais encontram dificuldades na manutenção do programa, sobretudo após a descentralização do setor saúde. Sabe-se que a sustentabilidade das ações de controle dos vetores da doença de Chagas depende da informação e participação comunitária. O presente trabalho avaliou os conhecimentos e práticas que a população de Bambuí, Minas Gerais, apresenta sobre os triatomíneos e a doença de Chagas. O conhecimento foi testado por meio da aplicação de questionário acompanhado de seis figuras de hemípteros para identificação. Participaram da pesquisa tanto adultos, como crianças dos ensinos fundamental e médio das escolas rurais presentes no município. Os dados apontaram que a população de Bambuí tem bons conhecimentos gerais sobre os triatomíneos e a doença de Chagas em ambos os grupos (adultos e crianças), entretanto os conceitos se mostraram limitados quanto ao que fazer para evitar esses vetores invadindo domicílios. Os resultados ressaltam a necessidade de campanhas educativas no contexto do PCDCh como elemento fundamental da participação comunitária no combate aos triatomíneos.

Despite the success of the Chagas Disease Control Program (PCCD) in Brazil, some endemic areas have experienced difficulty in maintaining the program's activities, especially after the health system's decentralization, since the sustainability of control measures for Chagas disease and vectors is known to depend on information and community participation. This study aimed to analyze knowledge and practices related to vectors and Chagas disease in Bambuí, Minas Gerais State, Brasil. The population's knowledge was tested with a questionnaire, accompanied by six illustrations of triatomine bugs for identification. Both adults and primary and secondary schoolchildren in rural areas of the county participated in the research. The Bambuí population showed good overall knowledge on triatomines and Chagas disease in both groups (adults and children), although the concepts were limited to preventing the insect vector from invading houses. The results emphasize the importance of educational campaigns in the context of the program as a fundamental component of community participation in Chagas disease vector control.

Importância do método de obtençäo das dejeçöes dos triatomíneos na avaliaçäo da suscetibilidade triatomínica para Trypanosoma cruzi / Importance of the method for obtaining feces from triatominae in the assessment of triatomine susceptibility to Trypanosoma cruzi

Foi estudada a suscetibilidade de Dipetalogaster maximus, Rhodnius neglectus, R. prolixus, R. robustus, Triatoma infestans e T. rubrovaria ao Trypanosoma cruzi, através do xenodiagnóstico, em dois pacientes na fase aguda da doença de Chagas. Usaram-se como parâmetros o número de triatomíneos infectados e o número de tripanosomas excretados. A leitura do senodiagnóstico foi realizada pelos métodos da compressäo abdominal e o das dejeçöes espontâneas. Este foi mais eficiente que aquele, em relaçäo ao número de T. cruzi por lâmina pelo teste de Wilcoxon. Em um dos pacientes, tendo como parámetro o número de triatomíneos infectados, a suscetibilidade das espécies obedeceu a seguinte ordem: D. maximus e R. neglectus (100 por cento), R. robustus (95 por cento), R. prolixus e T. rubrovaria (90 por cento) e T. infestans (85 por cento). Nesse mesmo paciente, a suscetibilidade das espécies de triatomíneos, avaliada pelo número de T. cruzi excretados, usando-se compressäo abdominal, encontra-se na seguinte ordem: R. neglectus, R. prolixus, D. maximus e R. robustus, T. infestans e T. rubrovaria. Pelo método das dejeçöes, a ordem foi: D. maximus e r. prolixus, T. rubrovaria, R. robustus, T. infestans e R. negelctus. No outro paciente, esse parâmetro, em ambas as técnicas de leitura, mostrou a mesma ordem de suscetibilidade (R.neglectus, T. rubrovaria e T. infestans), porém, o número de tripanosomas excretados foi significativamente maior pelo método das dejeçöes espontâneas

[Importance of the method for obtaining feces from triatominae in the assessment of triatomine susceptibility to Trypanosoma cruzi]. / Importância do método de obtenção das dejeções dos triatomíneos na avaliação da suscetibilidade triatomínica para Trypanosoma cruzi.

Two patients on the acute phase of Chagas' disease were submitted to xenodiagnosis examination with different species of triatomine bugs, in order to study bug susceptibility to Trypanosoma cruzi. Species used were Dipetalogaster maximus, Rhodnius neglectus, R. prolixus, R. robustus, Triatoma infestans and T. rubrovaria. Both the number of infected bugs, and the number of excreted trypanosomes by bug, were used as parameters for evaluation of species susceptibility. Xenodiagnosis reading was performed by two methods, the classic abdominal compression and the spontaneous dejection method; this was more efficient than the former in relation to the number of parasites per wet smear (by Wilcoxon test). When susceptibility was evaluated by the number of infected bugs, in one of the patients all D. maximus and R. neglectus became infected (100%), 95% of R. robustus, 90% of R. prolixus and T. rubrovaria, and 85% of T. infestans. When evaluation was performed through the number of excreted parasites in this patient with reading by abdominal compression, the higher susceptibility was with R. neglectus, followed by R. prolixus, D. maximus and R. robustus, T. infestans and T. rubrovaria; reading by spontaneous dejection yielded better results for D. maximus and R. prolixus followed by T. rubrovaria, R. robustus, T. infestans and R. neglectus. For the other patient susceptibility evaluated by the number of excreted parasites was similar by both reading methods and did show the same susceptibility pattern (R. neglectus and then T. rubrovaria and T. infestans), but the number of excreted trypanosomes was much higher by the spontaneous dejection method.

Estudo do controle dos triatomíneos domiciliados no estado de Säo Paulo

O Programa de Controle da doença de Chagas no Estado de Säo Paulo iniciou-se em 1950. No decorrer desses anos foi possível caracterizá-lo em fases bem definidas, de acordo com as estruturas administrativas envolvidas na sua execuçäo e extensäo do trabalho realizado pelos órgäos que precederam a atual Superintendência de Controle de Endemias - SUCEN. A base do Programa tem sido, desde a sua origem, o combate ao triatomíneos domiciliados, vetores da doença, particularmente o Triatoma infestans, através da aplicaçäo do inseticida (BHC) nos domicílios e anexos da zona rural do Estado. No início dos anos 70, alcançou-se a interrupçäo de transmissäo natural da endemia por triatomíneos, no meio rural paulista. Em que pesem as variaçöes no volume de trabalho executado, as açöes de controle lograram reduzir drasticamente as populaçöes de Triatoma infestans e em menor grau das duas espécies consideradas secundárias na transmissäo, Triatoma sordida e Panstrongylus megistus. Após esse período, o programa se estruturou no sentido de manter essa situaçäo, evoluindo gradativamente para uma situaçäo vigilância entomológica. Embora seja indiscutível o papel prenponderante das açöes de controle no processo de interrupçäo da transmissäo, outros fatores contribuiram para o resultado, quais sejam, aqueles ligados ao desenvolvimento econômico do meio rural paulista. A análise desse desenvolvimento indica que a doença de Chagas vem perdendo ao longo dos anos, os determiantes de sua expansäo e manutençäo como endemia rural, processo no qual se incluem os mecanismos de intervençäo do Estado. A avaliaçäo que se faz hoje do programa de controle aponta para a necessidade de nova orientaçäo, que busque incorporar à análise técnica - dos determinantes biológicos da infestaçäo residual por triatomíneos, os elementos da visäo estrutural - organizaçäo do espaço rural, que situa os limites dessa açäo no tempo e no espaço. Diante desse quadro, procurou-se estudar as açöes de controle dos triatomíneos desenvolvida no Estado, desde sua origem até os dias atuais, enfocando três níveis de explicaçäo. O conhecimento técnico-científico da endemia chagásica, a organizaçäo do serviço de controle e alguns elementos da estrutura social claramente ligados ao processo. Do encadeamento dos fatos históricos e da análise da situaçäo atual. propôs-se elementos para um sistema de vigilância epidemiológica

Chagas: uma doença escondida

Mostra o que é a doença de Chagas, contando um pouco da história de sua descoberta e evolução. Apresenta as formas de contaminação, especificamente pelo inseto conhecido por barbeiro. Discorre sobre seus sintomas e a forma de tratamento, bem como as ações de saúde que visam prevenir e até mesmo erradicar a doença