Optimising the surveillance of Aedes aegypti in Brazil by selecting smaller representative areas within an endemic city.

OBJECTIVES: Arboviruses, such as dengue (DENV), zika (ZIKV), and chikungunya (CHIKV), constitute a growing urban public health threat. Focusing on Aedes aegypti mosquitoes, their primary vectors, is crucial for mitigation. While traditional immature-stage mosquito surveillance has limitations, capturing adult mosquitoes through traps yields more accurate data on disease transmission. However, deploying traps presents logistical and financial challenges, demonstrating effective temporal predictions but lacking spatial accuracy. Our goal is to identify smaller representative areas within cities to enhance the early warning system for DENV outbreaks. METHODS: We created Sentinel Geographic Units (SGUs), smaller areas of 1 km2 within each stratum, larger areas, with the aim of aligning the Trap Positivity Index (TPI) and Adult Density Index (ADI) with their respective strata. We conducted a two-step evaluation of SGUs. First, we examined the equivalence of TPI and ADI between SGUs and strata from January 2017 to July 2022. Second, we assessed the ability of SGU's TPI and ADI to predict DENV outbreaks in comparison to Foz do Iguaçu's Early-Warning System, which forecasts outbreaks up to 4 weeks ahead. Spatial and temporal analyses were carried out, including data interpolation and model selection based on Akaike information criteria (AIC). RESULTS: Entomological indicators produced in small SGUs can effectively replace larger sentinel areas to access dengue outbreaks. Based on historical data, the best predictive capability is achieved 2 weeks after infestation verification. Implementing the SGU strategy with more frequent sampling can provide more precise space-time estimates and enhance dengue control. CONCLUSIONS: The implementation of SGUs offers an efficient way to monitor mosquito populations, reducing the need for extensive resources. This approach has the potential to improve dengue transmission management and enhance the public health response in endemic cities.

Entomo-virological surveillance followed by serological active survey of symptomatic individuals is helpful to identify hotspots of early arbovirus transmission.

Arboviruses transmitted by Aedes aegypti in urban environments have spread rapidly worldwide, causing great impacts on public health. The development of reliable and timely alert signals is among the most important steps in designing accurate surveillance systems for vector-borne diseases. In July and September 2017, we conducted a pilot study to improve an existing integrated surveillance system by using entomo-virological surveillance to prioritize areas to conduct active searches for individuals with arbovirus infection symptoms. Foz do Iguaçu City has a permanent entomo-virological surveillance system with approximately 3,500 traps to capture Aedes sp. in the adult stage. The Aedes aegypti females are captured alive and human samples are submitted to RT-qPCR (real-time qPCR) screening for DENV, ZIKV, and CHIKV diagnosis. Of the 55 Ae. aegypti mosquitoes tested in July 2017, seven (12.7%) were considered positive for DENV-2 and three (5.4%) for CHIKV. In September, we tested a sample of 54 mosquitoes, and 15 (27.7%) were considered infected by DENV-2. We created 25 circumferences with 150-m radius each to perform an active survey to identify symptomatic householders. In July, we selected one circumference, and five (35.7%) patients were positive for DENV, whereas two (14.3%) for CHIKV. In September, we selected four circumferences, and, from the 21 individuals sampled, nine (42.8%) were positive for DENV-2. A statistical model with a binomial response was used to estimate the number of cases in areas without active surveys, i.e., 20 circumferences. We estimated an additional 83 symptomatic patients (95% CI: 45-145) to be found in active searches, with 38 (95% CI: 18-72) of them confirming arbovirus infection. Arbovirus detection and serotyping in mosquitoes, but also in symptomatic individuals during active surveys, can provide an alert signal of early arbovirus transmission.

Adaptation of a Human Diagnostic Kit to Detect Dengue, Zika, and Chikungunya Viruses in Mosquito Samples (Aedes aegypti and Aedes albopictus): A Contribution to Public Health in the International Triple Border (Brazil, Paraguay, and Argentina).

Objective: The objective of this work was to adapt a diagnostic kit developed for humans to identify Dengue (DENV1, DENV2, DENV3, DENV4), Zika (ZIKV) and Chikungunya virus (CHIKV) in females of Aedes aegypti and Aedes albopictus and to verify if the occurrence of mosquitoes infected with these three arboviruses are being found in regions with high occurrence of these diseases in humans. Materials and Methods: For this purpose, live mosquitoes were captured between January and June 2020 using 3,476 traps permanently installed in the field were used. After capture, the species were identified, then the females were placed in a pool of 2 to 10 specimens and sent to the laboratory for detection of DENV1, DENV2, DENV3, DENV4, ZIKV and CHIKV by RT-PCR using a commercial human kit for arboviruses. Results: Of the 76 mosquito pools collected, six (7.9%) pools tested positive for the DENV2 virus. The DENV-positive mosquitoes were collected in regions with a high incidence of reported cases of Dengue or in adjacent areas. Conclusion: The absence of kits for the detection of these arboviruses in Aedes is a limiting factor and the adequacy of commercial kits, already used for the diagnosis of arboviruses in humans, the results presented demonstrate that it is possible to identify the presence of DENV2 in mosquitoes with the respective kit, reinforcing the use of RT-qPCR as a robust diagnostic tool for epidemiological surveillance allowing managers to receive timely results for decision-making regarding prevention and control actions.

Entomo-Virological Aedes aegypti Surveillance Applied for Prediction of Dengue Transmission: A Spatio-Temporal Modeling Study.

Currently, DENV transmitted primarily by Aedes aegypti affects approximately one in three people annually. The spatio-temporal heterogeneity of vector infestation and the intensity of arbovirus transmission require surveillance capable of predicting an outbreak. In this work, we used data from 4 years of reported dengue cases and entomological indicators of adult Aedes collected from approximately 3500 traps installed in the city of Foz do Iguaçu, Brazil, to evaluate the spatial and temporal association between vector infestation and the occurrence of dengue cases. Entomological (TPI, ADI and MII) and entomo-virological (EVI) indexes were generated with the goal to provide local health managers with a transmission risk stratification that allows targeting areas for vector control activities. We observed a dynamic pattern in the evaluation; however, it was a low spatio-temporal correlation of Ae. aegypti and incidence of dengue. Independent temporal and spatial effects capture a significant portion of the signal given by human arbovirus cases. The entomo-virological index (EVI) significantly signaled risk in a few areas, whereas entomological indexes were not effective in providing dengue risk alert. Investigating the variation of biotic and abiotic factors between areas with and without correlation should provide more information about the local epidemiology of dengue.

'Candidatus Mycoplasma haemoalbiventris' and tick-borne pathogens screening in white-eared opossums (Didelphis albiventris) from Curitiba and Foz do Iguaçu Cities, Paraná State, southern Brazil.

Hemoplasmas are epierythrocytic bacteria that infect mammals. 'Candidatus Mycoplasma haemoalbiventris' was detected in white-eared opossums (Didelphis albiventris) from southern and central-western Brazil. The present study aimed at: i) screening opossums for tick-borne (TBP) pathogens (Piroplasmida and Anaplasmataceae) and ii) detecting and characterizing hemoplasma species infecting opossums from Curitiba and Foz do Iguaçu cities in the Paraná State, southern Brazil. Thirty blood samples from white-eared opossums were evaluated by PCR assays. Animals were not infested by ectoparasites. The mammalian endogenous gapdh gene was consistently amplified in all samples. All opossums tested negative for Theileria/Babesia spp. and Ehrlichia/Anaplasma spp. by PCR based on 18S rRNA and 16S rRNA genes, respectively. A genus-specific PCR assay based on the 16S rRNA gene of hemoplasmas showed that three/13 (23.08%; CI 95%: 8.18-50.26%) opossums from Foz do Iguaçu were positive for hemotropic Mycoplasma sp. All opossums from Curitiba tested negative for hemoplasmas. Sequencing of both the 16S and 23S rRNA genes revealed that the animals were infected by 'Ca. M. haemoalbiventris'. Although 'Ca. M. haemoalbiventris' is prevalent in opossums in Brazil, clinical signs associated with its infection and its putative vectors remain unknown.

The adoption of the One Health approach to improve surveillance of venomous animal injury, vector-borne and zoonotic diseases in Foz do Iguaçu, Brazil.

Public health institutions with sectorized structure and low integration among field teams, old-fashioned practices such as paper-based storage system, and poorly qualified health agents have limited ability to conduct accurate surveillance and design effective timely interventions. Herein, we describe the steps taken by the Zoonosis Control Center of Foz do Iguaçu (CCZ-Foz) in the last 23 years to move from an archaic and sectorized structure to a modern and timely surveillance program embracing zoonotic diseases, venomous animal injuries, and vector-borne diseases epidemiology under the One Health approach. The full implementation of the One Health approach was based on 5 axes: (1) merging sectorized field teams; (2) adoption of digital solutions; (3) health agents empowerment and permanent capacitation; (4) social mobilization; and (5) active surveys. By doing so, notifications related to zoonotic diseases and venomous animals increased 10 and 21 times, respectively, with no impairment on arbovirus surveillance (major concern in the city). Open sources database (PostgreSQL) and software (QGis) are daily updated and create real-time maps to support timely decisions. The adoption of One Health approach increased preparedness for endemic diseases and reemerging and emerging threats such as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

'Candidatus Mycoplasma haemoalbiventris' and tick-borne pathogens screening in white-eared opossums (Didelphis albiventris) from Curitiba and Foz do Iguaçu Cities, Paraná State, southern Brazil / 'Candidatus Mycoplasma haemoalbiventris' e triagem para patógenos transmitidos por carrapatos em gambás de orelha branca (Didelphis albiventris) das cidades de Curitiba e Foz do Iguaçu, Estado do Paraná, sul do Brasil

Abstract Hemoplasmas are epierythrocytic bacteria that infect mammals. 'Candidatus Mycoplasma haemoalbiventris' was detected in white-eared opossums (Didelphis albiventris) from southern and central-western Brazil. The present study aimed at: i) screening opossums for tick-borne (TBP) pathogens (Piroplasmida and Anaplasmataceae) and ii) detecting and characterizing hemoplasma species infecting opossums from Curitiba and Foz do Iguaçu cities in the Paraná State, southern Brazil. Thirty blood samples from white-eared opossums were evaluated by PCR assays. Animals were not infested by ectoparasites. The mammalian endogenous gapdh gene was consistently amplified in all samples. All opossums tested negative for Theileria/Babesia spp. and Ehrlichia/Anaplasma spp. by PCR based on 18S rRNA and 16S rRNA genes, respectively. A genus-specific PCR assay based on the 16S rRNA gene of hemoplasmas showed that three/13 (23.08%; CI 95%: 8.18-50.26%) opossums from Foz do Iguaçu were positive for hemotropic Mycoplasma sp. All opossums from Curitiba tested negative for hemoplasmas. Sequencing of both the 16S and 23S rRNA genes revealed that the animals were infected by 'Ca. M. haemoalbiventris'. Although 'Ca. M. haemoalbiventris' is prevalent in opossums in Brazil, clinical signs associated with its infection and its putative vectors remain unknown.

Resumo Hemoplasmas são bactérias epieritrocíticas que infectam mamíferos. 'Candidatus Mycoplasma haemoalbiventris' foi detectado previamente em gambás-de-orelha-branca (Didelphis albiventris) das regiões sul e centro-oeste do Brasil. O presente estudo objetivou: i) triar os gambás para as doenças transmitidas por carrapatos (Piroplasmida e Anaplasmataceae); e ii) detectar e caracterizar as espécies de hemoplasma que infectam gambás nas cidades de Curitiba e Foz do Iguaçu, no Estado do Paraná, sul do Brasil. Trinta amostras de sangue de gambás-de-orelha-branca foram analisadas por PCR. Os animais não estavam infestados por ectoparasitos. O gene endógeno de mamífero gapdh foi amplificado em todas as amostras. Todos os gambás testaram negativos para Theileria/Babesia spp. e Ehrlichia/Anaplasma spp. por PCR, respectivamente, para os genes 18S rRNA e 16S rRNA. Uma PCR gene-específica, baseada no gene 16S rRNA de hemoplasmas, mostrou que três/13 (23,08%; CI 95%: 8,18-50,26%) gambás de Foz do Iguaçu foram positivos para Mycoplasma sp. hemotrópico. Todos os gambás de Curitiba testaram negativos para hemoplasmas. O sequenciamento de fragmentos dos genes 16S e 23S rRNA revelou que os animais estavam infectados pelo 'Ca. M. haemoalbiventris'. Embora 'Ca. M. haemoalbiventris' seja prevalente em gambás no Brasil, os sinais clínicos associados à infecção e os prováveis vetores permanecem desconhecidos.

Malathion insecticide resistance in Aedes aegypti: laboratory conditions and in situ experimental approach through adult entomological surveillance.

OBJECTIVE: In Brazil, the most common method of controlling outbreaks of arbovirus is by the use of chemical sprays, which kill the insect vector, Aedes aegypti. The main objective of this study was to evaluate the resistance of Ae. aegypti to the insecticide, malathion, in situ. The location of this study was the municipality of Foz do Iguaçu, in the state of Paraná, Brazil. METHODS: Ultra-low-volume (ULV) fogging equipment was used, by vehicle, to apply the insecticide in situ, and mosquito populations after treatment were compared with those of control areas. The resistance of strains collected from the municipality was compared to the Rockefeller strain under laboratory conditions. RESULTS: We found 220 adult female specimens and 7423 eggs of Ae. aegypti in the areas subjected to UBV treatment, whereas 245 adult females and 10 557 eggs were found in the control areas. The UBV treatment area showed no significant difference compared to the control area, for all the indices. Mortality of the Rockefeller colony varied more quickly when there were slight variations in malathion concentration than the Foz do Iguaçu population.

OBJECTIF: Au Brésil, la méthode la plus courante de lutte contre les épidémies d'arbovirus consiste à utiliser des pulvérisations chimiques qui tuent l'insecte vecteur, Aedes aegypti. L'objectif principal de cette étude était d'évaluer la résistance de Ae. aegypti à l'insecticide, le malathion, in situ. Le lieu de cette étude était la municipalité de Foz do Iguaçu, dans l'état du Paraná, au Brésil. MÉTHODES: Un équipement de brumisation à très faible volume (ULV) a été utilisé, par véhicule, pour appliquer l'insecticide in situ et les populations de moustiques après le traitement ont été comparées à celles des zones témoins. La résistance des souches collectées dans la municipalité a été comparée à la souche Rockefeller dans des conditions de laboratoire. RÉSULTATS: Nous avons trouvé 220 spécimens femelles adultes et 7.423 œufs d'Ae. aegypti dans les zones soumises au traitement ULV, alors que 245 femelles adultes et 10.557 œufs ont été trouvés dans les zones témoins. La zone de traitement ULV n'a montré aucune différence significative par rapport à la zone témoin, pour tous les indices. La mortalité de la colonie de Rockefeller variait plus rapidement lorsqu'il y avait de légères variations dans la concentration de malathion que la population de Foz do Iguaçu.

Uso de microrganismos de efluente industrial no controle biológico de vetores / Use of industrial effluent microorganisms in biological vector control / Uso de microorganismos de efluentes industriales en el control biológico de vectores

Justificativa e Objetivos: a utilização de microrganismos como controle biológico de vetores sanitários pode ser considerada uma prática menos agressiva ao ambiente, em comparação com os produtos químicos utilizados. O presente estudo avaliou a eficiência de suspensões celulares de fungos e bactérias isolados de efluentes industriais têxteis no controle sanitário dos vetores naturais Aedes aegypti e Dermacentor nitens como alternativa sustentável de controle biológico. Métodos: foram avaliadas sete linhagens de fungos e seis de bactérias. Os isolados foram cultivados em caldo nutriente e caldo de batata, para bactérias e fungos, respectivamente. Alíquotas de 2 mL de cada suspensão microbiana foram adicionadas diretamente nas larvas dos mosquitos e nos carrapatos adultos. Foram analisadas alterações de movimentação e paralisação dos vetores em diferentes tempos de exposição entre zero e 20 minutos e três e 24 horas. Resultados: duas bactérias e um fungo promoveram uma desaceleração dos movimentos e/ou um aumento da movimentação dos ectoparasitas logo após a administração. Dois isolados bacterianos promoveram a paralisação dos movimentos de uma larva do mosquito Aedes aegypti em seu primeiro estágio de desenvolvimento, enquanto que um fungo provocou aumento da movimentação das larvas em seu estágio de desenvolvimento mais avançado. Conclusão: os microrganismos mostraram potencial uso no controle de vetores sanitários. Testes subsequentes de atividade dos possíveis metabólitos secundários produzidos e das formas de administração das culturas microbianas serão executados. Os resultados encontrados encorajam futuros estudos de otimização e caracterização dos extratos celulares, os quais poderão ser utilizados como ferramenta sustentável no controle biológico.(AU)

Background and Objectives: the use of microorganisms as biological control of health vectors can be considered a less aggressive practice to the environment, in comparison with the chemicals used. The present study evaluated the efficiency of cell suspensions of fungi and bacteria isolated from industrial textile effluents in the sanitary control of the natural vectors Aedes aegypti and Dermacentor nitens as a sustainable alternative for biological control. Methods: seven fungi and six bacteria strains were evaluated. The isolates were grown in nutrient broth and potato broth, for bacteria and fungi, respectively. 2 mL aliquots of each microbial suspension were added directly to mosquito larvae and adult ticks. Changes in movement and paralysis of vectors at different exposure times between zero and 20 minutes and three and 24 hours were analyzed. Results: two bacteria and a fungus promoted a slowdown in movement and / or an increase in the movement of ectoparasites shortly after administration. Two bacterial isolates caused the movement of a larva of the Aedes aegypti mosquito to stop in its first stage of development, while a fungus caused increased movement of the larvae in their most advanced stage of development. Conclusion: the microorganisms showed potential use in the control of health vectors. Subsequent activity tests of the possible secondary metabolites produced and the ways of administering the microbial cultures will be performed. The results found encourage future studies of optimization and characterization of cell extracts, which can be used as a sustainable tool in biological control.(AU)

Justificación y objetivos: el uso de microorganismos como control biológico de vectores sanitarios puede considerarse una práctica menos agresiva para el medio ambiente en comparación con los productos químicos utilizados. El presente estudio evaluó la eficiencia de las suspensiones de células fúngicas y bacterianas de efluentes industriales textiles en el control sanitario de los vectores Aedes aegypti y Dermacentor nitens como una alternativa sostenible para el control biológico. Métodos: evaluaron siete hongos y seis de bacterias. Los aislamientos se cultivaron en medio de cultivo, caldo nutrientes y de papa para bacterias y hongos, respectivamente. Se agregaron alícuotas de 2 mL de cada suspensión microbiana directamente a las larvas de mosquito y las garrapatas adultas. Analizaron los cambios en el movimiento y la parálisis de los vectores a diferentes tiempos de exposición entre cero y 20 minutos y tres y 24 horas. Resultados: dos bacterias y un hongo causaron una reducido el movimiento y/o aumentó el movimiento del ectoparásito poco después de la administración. Dos bacterias paralizaron los movimientos de las larvas de un mosquito en su primera etapa de desarrollo y un hongo causó un mayor movimiento de las larvas en su etapa posterior de desarrollo. Conclusión: los microorganismos mostraron uso potencial como control de vectores sanitarios. Se realizarán pruebas de actividad de los posibles metabolitos secundarios producidos y las formas de administración de los cultivos microbianos. Los resultados fomentan más estudios de optimización y caracterización de extractos celulares, que pueden utilizarse como herramienta sostenible en el control biológico.(AU)

Molecular Detection of Dengue Virus in Mosquitoes as an Early Indicator to Aid in the Prevention of Human Infection in Endemic Areas.

Human cases of dengue virus based on the National Dengue Control Plan were compared with the molecular detection of the dengue virus in trapped mosquitoes, verifying the prediction and efficacy potentials of vector control between the two methodologies in a city with three endemic frontiers. Molecular detection of dengue virus in trapped mosquitoes was significantly higher than in human cases (p = 0.0435). Thus, molecular detection could be used as an early indicator to help prevent more human cases of dengue.

Epidemiological relevance of dogs for the prevention of Toxoplasma gondii, Neospora caninum and Leptospira spp.

This study evaluated the seroprevalence of Toxoplasma gondii, Neospora caninum and Leptospira spp. in dogs from Foz do Iguaçu, Paraná, Brazil. Indirect immunofluorescent antibody test was used to detect antibodies anti-T.gondii and anti-N. caninum. Immunoenzymatic assay and microscopic serum agglutination were used for screening antibodies anti-T.gondii and anti-Leptospira spp., respectively. The results were: 67.02% of the samples reactive for T.gondii and 1.38% for N. caninum, both without statistically significant variables. For Leptospira spp. the results indicated seroprevalence of 23.11%. The analysis of the variables without distinction of serovar showed association for intrinsic characteristics as breed, age, nutritional status and dog category. The extrinsic variables as city region and access to the street presented association (p<0.05). The most prevalent serovars were: Canicola 59.47%; Bratislava 13.07% and Butembo 15.68%. Variables that make up the adjusted multiple analysis model using Leptospira spp. were: age, breed and nutritional status; serovar Canicola, sex, nutritional status and area (p<0.05); serovar Bratislava, lymphadenomegaly and presence of fleas (p<0.05). Given the results obtained, dogs can be used as sentinels for toxoplasmosis and leptospirosis in Foz do Iguaçu and other cities with similar outcomes. In addition, preventive measures should be taken by health authorities because they are zoonoses and humans are also at risk.

Epidemiological relevance of dogs for the prevention of Toxoplasma gondii, Neospora caninum and Leptospira spp / Relevância epidemiológica de cães para a prevenção de Toxoplasma gondii, Neospora caninum e Leptospira spp

Abstract This study evaluated the seroprevalence of Toxoplasma gondii, Neospora caninum and Leptospira spp. in dogs from Foz do Iguaçu, Paraná, Brazil. Indirect immunofluorescent antibody test was used to detect antibodies anti-T.gondii and anti-N. caninum. Immunoenzymatic assay and microscopic serum agglutination were used for screening antibodies anti-T.gondii and anti-Leptospira spp., respectively. The results were: 67.02% of the samples reactive for T.gondii and 1.38% for N. caninum, both without statistically significant variables. For Leptospira spp. the results indicated seroprevalence of 23.11%. The analysis of the variables without distinction of serovar showed association for intrinsic characteristics as breed, age, nutritional status and dog category. The extrinsic variables as city region and access to the street presented association (p<0.05). The most prevalent serovars were: Canicola 59.47%; Bratislava 13.07% and Butembo 15.68%. Variables that make up the adjusted multiple analysis model using Leptospira spp. were: age, breed and nutritional status; serovar Canicola, sex, nutritional status and area (p<0.05); serovar Bratislava, lymphadenomegaly and presence of fleas (p<0.05). Given the results obtained, dogs can be used as sentinels for toxoplasmosis and leptospirosis in Foz do Iguaçu and other cities with similar outcomes. In addition, preventive measures should be taken by health authorities because they are zoonoses and humans are also at risk.

Resumo Este estudo avaliou a soroprevalência de Toxoplasma gondii, Neospora caninum e Leptospira spp. em cães de Foz do Iguaçu, Paraná, Brasil. O teste de imunofluorescência indireta foi utilizado para detectar anticorpos anti-T. gondii e anti-N. caninum. Ensaio imunoenzimático e soroaglutinação microscópica foram utilizados para pesquisa de anticorpos anti-T. gondii e anti-Leptospira spp., respectivamente. Os resultados obtidos foram: 67,02% (435/649) das amostras reativas para T. gondii e, 1,38% (9/649) para N. caninum, ambas com ausência de variáveis significativas estatisticamente. Para Leptospira spp. os resultados indicaram soroprevalência de 23,11% (153/649). A análise das variáveis sem distinção de sorovar mostraram associação para caraterísticas intrísecas como raça, idade, estado nutricional e categoria de cães. Para as variáveis extrínsecas, a região da cidade e ter acesso à rua mostraram associação estatística (p<0,05). Os sorovares mais prevalentes foram: Canicola com 59,47% (91/153); Bratislava 13,07% (20/153) e Butembo 15,68% (24/153). As variáveis que compõem o modelo de análise multivariada ajustada usando como desfecho Leptospira spp. foram: idade, raça, estado nutricional e área. Para o sorovar Canicola, as variáveis significantes (p<0,05) foram sexo, estado nutricional e área; para o sorovar Bratislava, as variáveis significantes (p<0,05) foram linfadenomegalia e presença de pulgas. Dos resultados obtidos, cães podem ser usados como sentinelas para infecção por T. gondii e Leptospira spp. na cidade de Foz do Iguaçu e em outras cidades com desfechos similares. Além disso, medidas preventivas devem ser tomadas pelas autoridades de saúde, pois são zoonoses e os seres humanos também estão em risco.

Hidden danger: Unexpected scenario in the vector-parasite dynamics of leishmaniases in the Brazil side of triple border (Argentina, Brazil and Paraguay).

Every year about 3 million tourists from around the world visit Brazil, Argentina and Paraguay´s triple border region where the Iguaçu Falls are located. Unfortunately, in recent years an increasing number of autochthonous canine and human visceral leishmaniasis (VL) cases have been reported. The parasite is Leishmania (Leishmania) infantum and it is transmitted by sand flies (Phlebotominae). To assess the risk factors favorable for the establishment and spread of potential vectors the Centers for Disease Control and Prevention light trap (CDC-light trap) collections were made in the Foz do Iguaçu (FI) and Santa Terezinha de Itaipu (STI) townships and along two transects between them. Our study determined the Phlebotominae fauna, the factors that affect the presence and abundance of Lutzomyia longipalpis and Nyssomyia whitmani, the presence of L. infantum in different sand fly species and which Leishmania species are present in this region. Lutzomyia longipalpis was the prevalent species and its distribution was related to the abundance of dogs. Leishmania infantum was found in Lu. longipalpis, Ny. whitmani, Ny. neivai and a Lutzomyia sp. All the results are discussed within the Stockholm Paradigm and focus on their importance in the elaboration of public health policies in international border areas. This region has all the properties of stable VL endemic foci that can serve as a source of the disease for neighboring municipalities, states and countries. Most of the urban areas of tropical America are propitious for Lu. longipalpis establishment and have large dog populations. Pan American Health Organization´s initiative in supporting the public health policies in the border areas of this study is crucial and laudable. However, if stakeholders do not act quickly in controlling VL in this region, the scenario will inevitable become worse. Moreover, L. (Viannia) braziliensis found in this study supports the need to develop public health policies to avoid the spread of cutaneous leishmaniasis. The consequences of socioeconomic attributes, boundaries and frontiers on the spread of diseases cannot be neglected. For an efficient control, it is essential that urban planning is articulated with the neighboring cities.

Building Infestation Index for Aedes aegypti and occurrence of dengue fever in the municipality of Foz do Iguaçu, Paraná, Brazil, from 2001 to 2016.

INTRODUCTION: the Building Infestation Index (BII) uses the Rapid Assay of the Larval Index for Aedes aegypti (LIRAa) to express the relationship between positive and surveyed properties. We evaluated LIRAa and the relationship between the BII and climate variables for dengue cases in Foz do Iguaçu municipality, Paraná. METHODS: Spearman's correlations for mean precipitation, mean temperature, BII, and dengue cases (time lag). RESULTS: positive correlations between BII and cases, and mean temperature and cases at two months. Weak correlation between precipitation and cases at three months. CONCLUSIONS: LIRAa and climate variables correlate with dengue cases.

Building Infestation Index for Aedes aegypti and occurrence of dengue fever in the municipality of Foz do Iguaçu, Paraná, Brazil, from 2001 to 2016

Abstract INTRODUCTION: the Building Infestation Index (BII) uses the Rapid Assay of the Larval Index for Aedes aegypti (LIRAa) to express the relationship between positive and surveyed properties. We evaluated LIRAa and the relationship between the BII and climate variables for dengue cases in Foz do Iguaçu municipality, Paraná. METHODS: Spearman's correlations for mean precipitation, mean temperature, BII, and dengue cases (time lag). RESULTS: positive correlations between BII and cases, and mean temperature and cases at two months. Weak correlation between precipitation and cases at three months. CONCLUSIONS: LIRAa and climate variables correlate with dengue cases.

More than the eyes can see: The worrying scenario of canine leishmaniasis in the Brazilian side of the triple border.

A cross-sectional epidemiological study in the extreme-west of the state of Paraná was carried out to access the prevalence, distribution, and risk variables of canine Visceral Leishmaniases (cVL). This study was conducted in three areas, two cities of far west of Parana state: Foz do Iguaçu (FI) and Santa Terezinha de Itaipu (STI), and along two transects between these two municipalities. To sample the entire urban area, the cities (FI and STI) were divided into a grid of squares of 400 m2 (patch). Among the 526 patches, 123 in FI, 40 in the transects and 33 in STI were selected according to the 'worst scenario' criterion. In the transect areas, in each 0.86 km five dogs from houses were surveyed to leishmaniasis. In each patch, blood of five dogs from houses (and from neighborhood when necessary) in the areas that seemed to be the most appropriate for the proliferation of vector were surveyed. The infection of the dogs by cVL were assessed using two serological tests were used (cELISA and TR-DPP®), and, for those seropositive for both methods, the PCR method were used. Moreover, dogs presenting clinical signs or cutaneous lesions were sampled to PCR. The identification of Leishmania species was confirmed using PCR-RFLP followed by DNA sequencing. Micro, meso and macro scale environmental variables were also surveyed and statistically analyzed. The prevalence rate Leishmania infantum was 23.8% in FI, 4.7% in STI and 9.1% in the transects areas. Among the extrinsic variables analysed, the number of vectors and the presence of infected dogs in neighbouring were positively correlated with the occurrence of infected dogs. Dog size was positively correlated with cVL infection, while the quality of the dog's nutrition affected cVL negatively. As for cutaneous leishmaniasis (CL), the first registry of dogs infected with L. braziliensis in the region shows that there is potential for transmission in peri-urban areas, since environmental conditions allow the proliferation of vectors capable of transmitting this species of parasite. cVL is widely spread in FI, with high prevalence. This supports the hypothesis that the parasite has been present in the region for longer than previously believed, despite the fact that the presence of leishmaniais in the region has only been recognized recently. It is important to control the population of dogs infected with L. infantum (parasite and non-antibodies) to prevent the spread of the disease to other dogs and also to people in the region.

Estimação da infestação predial por Aedes aegypti (Díptera: Culicidae) por meio da armadilha Adultrap / Estimation of House Infestation by Aedes aegypti (Diptera: Culicidae) Using Adultrap

Foi utilizada a armadilha Adultrap® em uma amostra de domicílio preconizada pelo levantamento de índice rápido de infestação por Aedes aegypti (LIRAa) para mensuração do número de adulto de Aedes aegypti no domicílio. Foi vistoriada uma média de 555 imóveis/mês: 15 unidades continham criadouros da espécie; e 53, a presença de fêmeas. O índice de infestação para larva/pupa (IPL) variou de zero ao máximo de 4,97 por cento, enquanto o índice de infestação para adulto (IPA), de 2,21 a 17,32 por cento. O teste de MacNemar mostrou diferenças significativas entre a positividade de IPL e IPA em todos os meses do ano. Além disso, detectaram-se fêmeas de Ae. aegypti em período de baixa densidade populacional, sem o caráter invasivo e incômodo da pesquisa de recipientes para o IPL. A Adultrap® mostrou-se útil para revelar situações propícias à transmissão da dengue, bem como de fácil operacionalidade.

It was analyzed the application of the Adultrap® in a same sample of the reading of the fast house index for measuring the number of adults of Aedes aegypti (LIRAa) in a domicile or premise. From the average of 555 premise/month, 15 units had breeding sites for the species and 53 showed the presence of females. The house index for larva/pupa (IPL) varied from zero to the maximum of 4.97 per cent, while the house index for adult (IPA) was from 2.21 to 17.32 per cent. The MacNemar test showed significant differences between the positivity of IPL and IPA in every month of the year. Moreover, it detected females of Ae. aegypti in period of low population density, without the invasive and nuisance character of container researching for the IPL. The Adultrap® revealed to be useful to identify situations of dengue transmission, as well easiness in operational use.

[Specificity of the Adultrap for capturing females of Aedes aegypti (Diptera: Culicidae)]. / Especificidade da armadilha Adultrap para capturar fêmeas de Aedes aegypti (Diptera: Culicidae).

The Adultrap is a new trap built for capturing females of Aedes aegypti. Tests were carried out to evaluate the specificity of this trap in comparison with the technique of aspiration of specimens in artificial shelters. Adultraps were kept for 24 hours inside and outside 120 randomly selected homes in two districts of the city of Foz do Iguaçú, State of Paraná. The statistical test was Poissons log-linear model. The result was 726 mosquitoes captured, of which 80 were Aedes aegypti. The Adultrap captured only females of this species, while the aspiration method captured both sexes of Aedes aegypti and another five species. The Adultrap captured Aedes aegypti inside and outside the homes, but the analysis indicated that, outside the homes, this trap captured significantly more females than aspiration did. The sensitivity of the Adultrap for detecting females of Aedes aegypti in low-frequency situations was also demonstrated.

Especificidade da armadilha Adultrap para capturar fêmeas de Aedes aegypti (Diptera: Culicidae) / Specificity of the Adultrap for capturing females of Aedes aegypti (Diptera: Culicidae)

A Adultrap é uma nova armadilha feita para capturar fêmeas de Aedes aegypti. Foram realizados testes para avaliar sua especificidade tendo como referência a técnica da aspiração da espécie em abrigos artificiais. A Adultrap ficou exposta por 24 horas no intradomicílio e peridomicílio de 120 casas sorteadas em dois bairros da Cidade de Foz do Iguaçu, Estado do Paraná. O teste estatístico foi o modelo log-linear de Poisson. O resultado foi a captura de 726 mosquitos Culicidae, dos quais 80 eram Aedes aegypti. A Adultrap capturou apenas fêmeas desta espécie, enquanto o aspirador os dois sexos de Aedes aegypti e mais cinco outras espécies. A Adultrap capturou Aedes aegypti dentro e fora das casas, mas a análise indicou que no peridomicílio a armadilha capturou significantemente mais fêmeas do que a aspiração. Também, ficou evidenciada a sensibilidade da Adultrap para detectar Aedes aegypti em situação de baixa freqüência.

The Adultrap is a new trap built for capturing females of Aedes aegypti. Tests were carried out to evaluate the specificity of this trap in comparison with the technique of aspiration of specimens in artificial shelters. Adultraps were kept for 24 hours inside and outside 120 randomly selected homes in two districts of the city of Foz do Iguaçú, State of Paraná. The statistical test was Poisson's log-linear model. The result was 726 mosquitoes captured, of which 80 were Aedes aegypti. The Adultrap captured only females of this species, while the aspiration method captured both sexes of Aedes aegypti and another five species. The Adultrap captured Aedes aegypti inside and outside the homes, but the analysis indicated that, outside the homes, this trap captured significantly more females than aspiration did. The sensitivity of the Adultrap for detecting females of Aedes aegypti in low-frequency situations was also demonstrated.