Spatial distribution and population dynamics of free-roaming (stray and semi-domiciled) dogs in a major Brazilian city.

Introduction: Although estimate models have been proposed to determine free-roaming (both stray and semi-domiciled) dog populations, to date, no study has focused on the three major border areas of Brazil. Therefore, the present study assessed the free-roaming dog population of Foz do Iguaçu, a major far-west Brazilian city located in a three-border area (Brazil, Argentina, and Paraguay), which is considered among the top five Brazilian tourist destinations. Methods: Capture-release sampling was performed in three phases with a 6-month interval and 10-day duration of each phase, totaling 18 months, between 2018 and 2019. Results: A total of 1,273 dogs were estimated in the first [95% confidence interval (CI), 468-2,078 dogs], 904 in the second (95%CI, 452-1,355 dogs), and 1,564 in the third (95%CI, 521-2,607 dogs) capture phases in this area, suggesting a population density of 18.4 dogs/km2 (6.1-30.6 dogs/km2, 95% CI). Of all free-roaming dogs, 452/1,125 (40.2%) were stray with no confirmed ownership or household, whereas 672/1,125 (59.8%) had a known origin, among which 625/1,125 (55.6%) were semi-domiciled with ownership or a household, 36/1,125 (3.2%) were neighborhood dogs with maintainers, and 11/1,125 (1.0%) were owned by recycling material collectors and homeless individuals. The majority of the 1,125 dogs (862/1,125; 76.6%) had an ideal body condition score. The high outdoor access of owned dogs is likely caused by cultural behavior. However, because 533/1,125 (47.4%) of the free-roaming dogs presented with clinical abnormalities, irresponsible ownership may have negatively impacted dog health and welfare. Discussion: This study was the first to establish the density of free-roaming dogs, the ratio of stray and semi-domiciled dogs, and their dynamics over time in Foz do Iguaçu. The findings may serve as a warning for the high level of dog outdoor access and irresponsible guardianship, which may negatively affect animal health and welfare, leading to diseases, accidents, trauma, and animal cruelty.

'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.