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.

SARS-CoV-2 Research in Dogs (Canis lupus familiaris) and Felines (Felis silvestris catus) Domiciled in an International Border Region (Paraguay and Brazil).

Introduction: COVID-19 is an infectious disease caused by SARS-CoV-2 that has become a serious threat to public health owing to its rapid spread from aerosols from infected people. Despite being considered a strictly human disease, there are reports in the literature about animals with confirmed presence of the virus. Aim: Owing to the scarcity of scientific literature on the potential for infection of animals and their importance for One Health, the objective of this work was to research SARS-CoV-2 RNA in felines (Felis silvestris catus) and dogs (Canis lupus familiaris) domiciled. Materials and Methods: Oropharyngeal swabs were collected from domestic dogs and cats belonging to patients diagnosed with COVID-19 from August to October 2021 and residents of the northwest and west regions of Paraná, Brazil. Results: Of the 34 samples collected, 14 were from dogs and 20 from cats. Three of these samples tested positive in real-time PCR, and two of them were also positive in the immunochromatographic test. After testing positive in real-time PCR, the samples underwent genetic sequencing using the Illumina COVIDSeq test. Of the 34 samples collected, three (9%), all of them female and from the feline species, tested positive in real-time PCR, with two of these (67%) also testing positive in the immunochromatographic test. Regarding sequencing, it was possible to sequence the three samples aligned with the AY.101 lineage, corresponding to the Delta variant. Conclusion: The occurrence of SARS-CoV-2 infection in dogs and cats is seen as an unintended event with significant implications for public health, including its potential transmission to other animal species. Further research is required to enhance our understanding of how this disease spreads among these animals and its broader impact on One Health initiatives.

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.

Urban capuchin monkeys Sapajus nigritus (Goldfuss, 1809) (Primates, Cebidae) as environmental bioindicators of leishmaniasis.

The aim of this study was to investigate the presence of Leishmania sp. DNA and anti-Leishmania spp. antibodies in free-ranging Sapajus nigritus from an urban forest located in a city in the North Central region of the state of Paraná. For the indirect diagnosis, the direct agglutination test was used with promastigote forms of Leishmania (V.) braziliensis, where it was possible to detect the agglutination reaction in 53.33% of the S. nigritus blood samples. For direct diagnosis, the samples were submitted to real-time quantitative polymerase chain reaction, which confirmed the presence of Leishmania spp. DNA in 26.66% of the tested samples. It reinforces the importance of considering the concept of One Health in the face of diseases with high prevalence, such as leishmaniasis and the need for health education measures. This result shows that the animals in the present study have a role as environmental bioindicators for leishmaniasis.

'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.

Urban Horses As Environmental Bioindicators for Leishmaniasis.

The presence of DNA and anti-Leishmania spp. antibodies in the serum of 112 healthy horses was investigated by evaluating the physical examination, from a rural society located in the north central region of Paraná. The antigens of Leishmania amazonensis, Leishmania braziliensis, and Leishmania infantum were used to perform the indirect enzyme-linked immunosorbent assay, where it was possible to detect the reaction in 27.67% of the samples. These were also subjected to the real-time quantitative PCR, which confirmed the presence of Leishmania spp. DNA in 67.34% of the tested samples. The results show that the tested animals were previously exposed to the protozoan. Thus, these animals can be considered environmental bioindicators of the presence of Leishmania spp. at the study site. The material used in this study (serum), although not ideal, proved to be effective and less invasive. Taking into account the importance of the disease, the absence of more in-depth information on the species, the high zootechnical value of these animals, and their strictly close contact with the urban area and the human species, it is essential that further studies are carried out to elucidate the epidemiological profile of them in the face of the disease, as well as the possibility of them acting not only as hosts but also as reservoirs.

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.

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.

Estudo da conservação de material biológico com a tecnologia Fta-card® / Study on the conservation of biological material with Fta-card® technology / Estudio de conservación de material biológico con la tecnología Fta-card®

O Whatman FTA-Card® é um papel-filtro quimicamente tratado, destinado à coleta, transporte, armazenamento de amostras para posterior extração de ácidos nucléicos. A tecnologia FTA-Card® é utilizada para manter estável DNA e RNA em temperatura ambiente, podendo ser utilizados para fixação de uma ampla variedade de material orgânico ou tecidos. Foram realizados testes para certificar sua eficiência na conservação do material a ser analisado com o intuito de eliminar a cadeia fria de conservação, agilizando o processo e diminuindo os custos da execução de exames moleculares associados ao diagnóstico de patologias. Foram testadas oito amostras de felinos na forma de sangue total e soro, para a extração utilizou-se o kit Magazorb RNA Total mini-prep kit (Promega®, EUA), para o diagnóstico foi utilizada a técnica de PCR em tempo real para amplificar o gene CI2 de mamíferos, a fim de visualizar a eficácia na conservação de ácidos nucleicos. A utilização desse método torna possível que o material biológico seja enviado por serviços de transporte postais, reduzindo os custos e viabilizando diagnósticos provenientes de áreas mais remotas.(AU)

Whatman FTA-Card® is a chemically treated filter paper intended for the collection, transport, and storage of samples for later extraction of nucleic acids. FTA-Card® technology is used to keep DNA and RNA stable at room temperature and can be used to fix a wide variety of organic material or tissues. Tests were carried out to certify its efficiency in the conservation of the material to be analyzed in order to eliminate the cold conservation chain, speeding up the process and decreasing the costs of performing molecular tests associated with the diagnosis of pathologies. By using this method, biological material can be sent by postal transport services, reducing costs and making diagnoses from more remote areas feasible. Samples of feline specimens were tested in the form of whole blood and serum, using the Magazorb RNA Total mini-prep kit (Promega®, USA) for the extraction. Diagnosis was performed using real-time PCR technique to amplify the mammalian CI2 gene in order to visualize the effectiveness in conserving nucleic acids.(AU)

Whatman FTA-Card® es un papel de filtro tratado químicamente, destinado a la recogida, transporte, almacenamiento de muestras para su posterior extracción de ácidos nucleicos. La tecnología FTA-Card® se usa para mantener el ADN y el ARN estables a la temperatura ambiente y se puede usar para la fijación de una amplia variedad de materiales o tejidos orgánicos. Se realizaron pruebas para certificar su eficiencia en la conservación del material a analizar con el fin de eliminar la cadena de frío de conservación, agilizando el proceso y reduciendo los costos de realización de pruebas moleculares asociadas al diagnóstico de patologías. Se analizaron ocho muestras felinas en forma de sangre total y suero, para la extracción se utilizó el mini-prep kit Magazorb RNA Total (Promega®, USA), para el diagnóstico se utilizó la técnica de PCR en tiempo real para amplificar el CI2 de mamífero gen, con el fin de visualizar la efectividad en la conservación de ácidos nucleicos. El uso de ese método permite el envío de material biológico por los servicios de transporte postal, lo que reduce los costes y permite realizar diagnósticos desde zonas más remotas.(AU)

'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.

Efeitos da ingestão de semente de linhaça e seu possivel efeito hipocolesterolêmico / Effects of linseed intake and its possible hypocholesterolemic effects

Introdução: O colesterol é essencial para a vida. Em excesso no sangue, deposita-se nas paredes das artérias promovendo seu estreitamento ou obstrução. Objetivos: O objetivo foi verificar o possível efeito hipocolesterolêmico da semente de linhaça. Materiais e Métodos: Utilizaram-se 30 ratos Wistar fêmeas divididos em três grupos: Controle, Hipercolesterolêmico, e Linhaça. Os parâmetros avaliados foram: ingestão hídrica; ingestão de ração; peso corporal; gordura peritoneal e níveis de colesterol; Resultados e Discussão: O grupo controle apresentou maior ingestão hídrica (57,46 ± 0,13mL) e ração (30,68 ± 1,96g) quando comparados ao hipercolesterolêmico e linhaça; Para peso corporal total, somente o controle não sofreu alteração; Em relação ao acúmulo de gordura peritoneal, o grupo hipercolesterolêmico se sobressaiu (17,06 ± 3,99g) em comparação ao linhaça e ao controle; para os níveis de colesterol sérico, o grupo controle obteve (1,14 ± 0,14g), sendo observado portanto no grupo linhaça (1,66 ± 0,16g), uma maior aproximação para o resultado do grupo controle do que do hipercolesterolêmico (2,20 ± 6,32g), resultado que nos leva a reconhecer que a linhaça surtiu efeito benéfico sobre o colesterol. Conclusão: Os resultados obtidos demonstram benefícios na utilização da semente para redução dos níveis de gordura peritoneal, peso total e colesterol

Introduction: Cholesterol is essential for life, when in excess in blood, is deposited on the artery walls promoting its narrowing or obstruction. Objectives: The objective was to verify the possible hypocholesterolemic effect of linseed. Methods: We used 30 female Wistar rats divided into three groups: control, hypercholesterolemic, and linseed. The evaluated parameters were: water intake, feed intake, body weight, peritoneal fat, and cholesterol levels; Results and Discussion: The results were: the control group had a higher fluid intake (57.46 ± 0.13ml) and feed (30.68 ± 1.96g) when compared to hypercholesterolemic and linseed; for total body weight, only the control group did not change; in relation to the accumulation of peritoneal fat, the hypercholesterolemic group stood out (17.06 ± 3.99g) compared to linseed and control; for serum cholesterol levels, the control group obtained (1.14 ± 0.14g), thus being observed in linseed group (1.66 ± 0.16g), closer to the result of the control group than the hypercholesterolemic (2.20 ± 6.32g), a result that leads us to recognize that linseed has had a beneficial effect on cholesterol.Conclusion: The results obtained demonstrate benefits in the use of the seed to reduce levels of peritoneal fat, total weight and cholesterol

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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.