Navegando por Autor "Secundino, Nagila Francinete Costa"
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Item Aedes (Stegomyia) albopictus’ dynamics influenced by spatiotemporal characteristics in a Brazilian dengue-endemic risk city.(2016) Bezerra, Juliana Maria Trindade; Araújo, Raphaela Guedes Pereira; Melo, Fabrício Freire de; Gonçalves, Caroline Macedo; Chaves, Bárbara Aparecida; Silva, Breno de Mello; Silva, Luciana Diniz; Brandão, Silvana Tecles; Secundino, Nagila Francinete Costa; Norris, Douglas; Pimenta, Paulo Filemon PaolucciBrazil reported the majority of the dengue cases in Americas during the last two decades, where theoccurrence of human dengue cases is exclusively attributed to the Aedes (Stegomyia) aegypti (Linnaeus).Nowadays, other recognized Dengue virus (DENV) vector in Asian countries, Aedes (Stegomyia) albopictus(Skuse), has been detected in more than half of the 5565 Brazilian municipalities. Therefore, the aim of thepresent study was to investigate the presence of, and determine the Ae. albopictus’ dynamics influencedby spatiotemporal characteristics in a dengue-endemic risk city of Belo Horizonte, Minas Gerais State’scapital. Aedes albopictus were collected across four consecutive DENV transmission seasons from 2010 to2014. These mosquitoes were caught in three selected districts, which had been reported in the previousten years as having high mosquito densities and an elevated concentration of human dengue cases dur-ing epidemic seasons. All field-caught Ae. albopictus was individually processed by real-time RT-PCR, toresearch the DENV presence. The third season (p < 0.05) and the Pampulha district (p < 0.05) had the high-est proportions of field-caught Ae. albopictus, respectively. The second season had the highest proportionof DENV-infected field-caught females (p < 0.05), but there was no difference among the proportions ofDENV-infected Ae. albopictus when comparing the collection in the three districts (p = 0.98). Minimum(p = 0.004) and maximum (p < 0.0001) temperature were correlated with the field-caught Ae. albopic-tus in four different periods and districts. In the generalized linear model of Poisson, the field-caughtDENV-infected Ae. albopictus (p = 0.005), East district (p = 0.003), minimum temperature (p < 0.0001) andrelative humidity (p = 0.001) remained associated with the total number of human dengue cases. Ourstudy demonstrated that the number of field-caught DENV-infected Ae. albopictus was inversed corre-lated with the number of human dengue cases. Our study raises the possibility that the DENV circulating inmosquitoes Ae. albopictus is happening in non-epidemic periods, showing that this species may be keep-ing only the presence of the virus in nature. Further long-term studies are necessary to better understandthe role of Ae. albopictus in DENV transmission and or its vectorial competence in Belo Horizonte and inother endemic cities in Brazil and in the New World countries.Item Coinfection with Zika Virus (ZIKV) and dengue virus results in preferential ZIKV transmission by vector bite to vertebrate host.(2018) Chaves, Bárbara Aparecida; Orfanó, Alessandra da Silva; Nogueira, Paula Monalisa; Rodrigues, Nilton Barnabé; Campolina, Thaís Bonifácio; Pimenta, Rafael Nacif; Pires, Ana Clara Araújo Machado; Vieira Junior, Ademir Bentes; Paz, Andréia da Costa; Vaz, Evelyn Beatriz da Costa; Guerra, Maria das Graças Vale Barbosa; Silva, Breno de Mello; Melo, Fabrício Freire de; Norris, Douglas Eric; Lacerda, Marcus Vinícius Guimarães de; Pimenta, Paulo Filemon Paolucci; Secundino, Nagila Francinete CostaBackground. Several tropical cities are permissive to Aedes aegypti and dengue virus (DENV) endemicity and have allowed for invasion and circulation of Zika virus (ZIKV) in the same areas. People living in arbovirus-endemic regions have been simultaneously infected with ≥2 arboviruses. Methods. A. aegypti mosquitoes from Manaus, the capital city of Amazonas State in Brazil, were coinfected with circulating strains of DENV and ZIKV. The coinfected vectors were allowed to bite BALB/c mice. Results. A. aegypti from Manaus is highly permissive to monoinfection and coinfection with DENV and ZIKV and is capable of cotransmitting both pathogens by bite. Coinfection strongly influences vector competence, favoring transmission of ZIKV to the vertebrate host. Conclusions. This finding suggests that A. aegypti is an efficient vector of ZIKV and that ZIKV would be preferentially transmitted by coinfected A. aegypti. Coinfection in the vector population should be considered a new critical epidemiological factor and may represent a major public health challenge.Item Dengue infection susceptibility of five Aedes aegypti populations from Manaus (Brazil) after challenge with Virus Serotypes 1-4.(2022) Chaves, Bárbara Aparecida; Godoy, Raquel Soares Maia; Campolina, Thaís Bonifácio; Vieira Junior, Ademir Bentes; Paz, Andréia da Costa; Vaz, Evelyn Beatriz da Costa; Silva, Breno de Mello; Nascimento, Rêgila Mello; Guerra, Maria das Graças Vale Barbosa; Lacerda, Marcus Vinícius Guimarães de; Monteiro, Wuelton Marcelo; Secundino, Nagila Francinete Costa; Pimenta, Paulo Filemon PaolucciThe successful spread and maintenance of the dengue virus (DENV) in mosquito vectors depends on their viral infection susceptibility, and parameters related to vector competence are the most valuable for measuring the risk of viral transmission by mosquitoes. These parameters may vary according to the viral serotype in circulation and in accordance with the geographic origin of the mosquito population that is being assessed. In this study, we investigated the effect of DENV serotypes (1–4) with regards to the infection susceptibility of five Brazilian Ae. aegypti populations from Manaus, the capital of the state of Amazonas, Brazil. Mosquitoes were challenged by oral infection with the DENV serotypes and then tested for the presence of the arbovirus using quantitative PCR at 14 days post-infection, which is the time point that corresponds to the extrinsic incubation period of Ae. aegypti when reared at 28 ◦C. Thus, we were able to determine the infection patterns for DENV-1, -2, -3 and -4 in the mosquito populations. The mosquitoes had both interpopulation and inter-serotype variation in their viral susceptibilities. All DENV serotypes showed a similar tendency to accumulate in the body in a greater amount than in the head/salivary gland (head/SG), which does not occur with other flaviviruses. For DENV-1, DENV-3, and DENV-4, the body viral load varied among populations, but the head/SG viral loads were similar. Differently for DENV-2, both body and head/SG viral loads varied among populations. As the lack of phenotypic homogeneity represents one of the most important reasons for the long-term fight against dengue incidence, we expect that this study will help us to understand the dynamics of the infection patterns that are triggered by the distinct serotypes of DENV in mosquitoes.Item Distinct variation in vector competence among nine field populations of Aedes aegypti from a Brazilian dengue-endemic risk city.(2014) Gonçalves, Caroline Macedo; Melo, Fabrício Freire de; Bezerra, Juliana Maria Trindade; Chaves, Bárbara Aparecida; Silva, Breno de Mello; Silva, Luciana Diniz; Pessanha, José Eduardo Marques; Arias, Jorge; Secundino, Nagila Francinete Costa; Norris, Douglas; Pimenta, Paulo Filemon PaolucciItem Vertical Transmission of Zika Virus (Flaviviridae, Flavivirus) in Amazonian Aedes aegypti (Diptera: Culicidae) delays egg hatching and larval development of progeny.(2019) Chaves, Bárbara Aparecida; Vieira Junior, Ademir Bentes; Silveira, Karine Renata Dias; Paz, Andréia da Costa; Vaz, Evelyn Beatriz da Costa; Araújo, Raphaela Guedes Pereira; Rodrigues, Nilton Barnabé; Campolina, Thaís Bonifácio; Orfanó, Alessandra da Silva; Pimenta, Rafael Nacif; Villegas, Luis Eduardo Martínez; Melo, Fabrício Freire de; Silva, Breno de Mello; Monteiro, Wuelton Marcelo; Guerra, Maria das Graças Vale Barbosa; Lacerda, Marcus Vinícius Guimarães de; Norris, Douglas Eric; Secundino, Nagila Francinete Costa; Pimenta, Paulo Filemon PaolucciZika virus (ZIKV) has emerged as a globally important arbovirus and has been reported from all states of Brazil. The virus is primarily transmitted to humans through the bite of an infective Aedes aegypti (Linnaeus, 1762) or Aedes albopictus (Skuse, 1895). However, it is important to know if ZIKV transmission also occurs from Ae. aegypti through infected eggs to her offspring. Therefore, a ZIKV and dengue virus (DENV) free colony was established from eggs collected in Manaus and maintained until the third–fourth generation in order to conduct ZIKV vertical transmission (VT) experiments which used an infectious bloodmeal as the route of virus exposure. The eggs from ZIKV-infected females were allowed to hatch. The resulting F1 progeny (larvae, pupae, and adults) were quantitative polymerase chain reaction (qPCR) assayed for ZIKV. The viability of ZIKV vertically transmitted to F1 progeny was evaluated by cultivation in C6/36 cells. The effects of ZIKV on immature development of Ae. aegypti was assessed and compared with noninfected mosquitoes. Amazonian Ae. Aegypti were highly susceptible to ZIKV infection (96.7%), and viable virus passed to their progeny via VT. Moreover, eggs from the ZIKV-infected mosquitoes had a significantly lower hatch rate and the slowest hatching. In addition, the larval development period was slower when compared to noninfected, control mosquitoes. This is the first study to illustrate VT initiated by oral infection of the parental population by using mosquitoes, which originated from the field and a ZIKV strain that is naturally circulating in-country. Additionally, this study suggests that ZIKV present in the Ae. aegypti can modify the mosquito life cycle. The data reported here suggest that VT of ZIKV to progeny from naturally infected females may have a critical epidemiological role in the dissemination and maintenance of the virus circulating in the vector.Item Zika virus transmission to mouse ear by mosquito bite : a laboratory model that replicates the natural transmission process.(2017) Secundino, Nagila Francinete Costa; Chaves, Bárbara Aparecida; Orfanó, Alessandra da Silva; Silveira, Karine Renata Dias; Rodrigues, Nilton Barnabé; Campolina, Thaís Bonifácio; Pimenta, Rafael Nacif; Villegas, Luis Eduardo Martínez; Silva, Breno de Mello; Lacerda, Marcus Vinícius Guimarães de; Norris, Douglas Eric; Pimenta, Paulo Filemon PaolucciBackground: Zika disease has transformed into a serious global health problem due to the rapid spread of the arbovirus and alarming severity including congenital complications, microcephaly and Guillain-Barré syndrome. Zika virus (ZIKV) is primarily transmitted to humans through the bite of an infective mosquito, with Aedes aegypti being the main vector. Methods: We successfully developed a ZIKV experimental transmission model by single infectious Ae. aegypti bite to a laboratory mouse using circulating Brazilian strains of both arbovirus and vector. Mosquitoes were orally infected and single Ae. aegypti were allowed to feed on mouse ears 14 days post-infection. Additionally, salivary gland (SG) homogenates from infected mosquitoes were intrathoracically inoculated into naïve Ae. aegypti. Mosquito and mouse tissue samples were cultured in C6/36 cells and processed by quantitative real-time PCR. Results: A total of 26 Ae. aegypti were allowed to feed individually on mouse ears. Of these, 17 mosquitoes fed, all to full engorgement. The transmission rate of ZIKV by bite from these engorged mosquitoes to mouse ears was 100%. The amount of virus inoculated into the ears by bites ranged from 2 × 102 –2.1 × 1010 ZIKV cDNA copies and was positively correlated with ZIKV cDNA quantified from SGs dissected from mosquitoes post-feeding. Replicating ZIKV was confirmed in macerated SGs (2.45 × 107 cDNA copies), mouse ear tissue (1.15 × 103 cDNA copies, and mosquitoes 14 days post-intrathoracic inoculation (1.49 × 107 cDNA copies) by cytopathic effect in C6/36 cell culture and qPCR. Conclusions: Our model illustrates successful transmission of ZIKV by an infectious mosquito bite to a live vertebrate host. This approach offers a comprehensive tool for evaluating the development of infection in and transmission from mosquitoes, and the vertebrate-ZIKV interaction and progression of infection following a natural transmission process.