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Racial inequalities in the development of multimorbidity of chronic conditions: results from a Brazilian prospective cohort
Full text linkProdução científica do Laboratório de Educação em Ambiente e Saúde.Antecedentes e objetivos: A ocorrência de multimorbidade e seus impactos têm afetado de forma diferenciada os subgrupos populacionais. As evidências sobre sua incidência provêm principalmente de regiões de alta renda, com exploração limitada das disparidades raciais. Este estudo investigou a associação entre grupos raciais e o desenvolvimento de multimorbidade e de condições crônicas no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Métodos: Foram analisados dados de participantes autodeclarados brancos, pardos (raças mistas) e pretos na linha de base do ELSA-Brasil (2008-2010) que estavam em risco para a multimorbidade. O desenvolvimento de condições crônicas foi avaliado a partir das visitas presenciais e autorrelato de diagnóstico por telefone até a terceira visita de seguimento (2017-2019). A multimorbidade foi definida quando na visita de seguimento o participante possuía duas ou mais morbidades. Foram estimadas incidências acumuladas, taxas de incidência e razões das taxas de incidência (RTI) ajustadas a partir de modelos de Poisson. Resultados: Em um acompanhamento de 8,3 anos, em comparação aos participantes brancos: os pardos tiveram uma incidência 27% maior de hipertensão e obesidade; e os pretos tiveram uma incidência 62% e 45% maior, respectivamente. Os pretos também tiveram 58% mais diabetes. A incidência de câncer foi maior entre os brancos. A multimorbidade afetou 41% dos participantes, com uma taxa bruta de incidência de 57,5 casos por 1.000 pessoasano (variando de 56,3 para brancos a 63,9 para pretos). Estimativas ajustadas mostraram incidência 20% maior de multimorbidade em pretos comparados aos brancos (RTI: 1,20; IC 95%: 1,05-1,38). Conclusões: Foram observadas disparidades raciais significativas no risco de condições crônicas e multimorbidade. Muitas associações revelaram um aumento gradiente no risco de doenças de acordo com tons de pele mais escuros. Abordar causas fundamentais como o racismo e a discriminação racial, juntamente com a consideração dos determinantes sociais da saúde, é vital para o cuidado abrangente da multimorbidade. Políticas intersetoriais e equitativas são essenciais para a garantia do direito à saúde aos grupos historicamente marginalizados.This work was supported by Brazil’s Ministry of Health and Ministry of Science, Technology and Innovation (to ELSA-Brasil).The Studies and Projects Funder—FINEP (to ELSA-Brasil).The National Scientific and Technological Development Council—CNPq (to ELSA-Brasil and Productivity Scholarship to Rosane Härter Griep).The Carlos Chagas Rio de Janeiro State Research Support Foundation—FAPERJ (PhD grant Nota 10 E-26/200,636/2021 to Fernanda Esthefane Garrides Oliveira; Young Scientist of Our State program E-26/201,277/2021 to Leonardo Soares Bastos Scientist of Our State program to Rosane Härter Griep and Maria de Jesus Mendes da Fonseca).The funders played no role in the study’s conceptualisation, design, data collection, analysis, decision to publish or preparation of the manuscript.Background: The occurrence of multimorbidity and its impacts have differentially affected population subgroups. Evidence on its incidence has mainly come from high-income regions, with limited exploration of racial disparities. This study investigated the association between racial groups and the development of multimorbidity and chronic conditions in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods: Data from self-reported white, brown (pardos or mixed-race), and black participants at baseline of ELSABrasil (2008–2010) who were at risk for multimorbidity were analysed. The development of chronic conditions was assessed through in-person visits and self-reported diagnosis via telephone until the third follow-up visit (2017–2019). Multimorbidity was defined when, at the follow-up visit, the participant had two or more morbidities. Cumulative incidences, incidence rates, and adjusted incidence rate ratios (IRRs) were estimated using Poisson models. Results: Over an 8.3-year follow-up, compared to white participants: browns had a 27% greater incidence of hypertension and obesity; and blacks had a 62% and 45% greater incidence, respectively. Blacks also had 58% more diabetes. The cancer incidence was greater among whites. Multimorbidity affected 41% of the participants, with a crude incidence rate of 57.5 cases per 1000 person-years (ranging from 56.3 for whites to 63.9 for blacks). Adjusted estimates showed a 20% higher incidence of multimorbidity in black participants compared to white participants (IRR: 1.20; 95% CI: 1.05–1.38). Conclusions: Significant racial disparities in the risk of chronic conditions and multimorbidity were observed. Many associations revealed a gradient increase in illness risk according to darker skin tones. Addressing fundamental causes such as racism and racial discrimination, alongside considering social determinants of health, is vital for comprehensive multimorbidity care. Intersectoral, equitable policies are essential for ensuring health rights for historically marginalized groups
Entomological assessment of hessian fabric transfluthrin vapour emanators for protecting against outdoor-biting Aedes aegypti in coastal Tanzania
Full text linkProdução científica do Laboratório de Fisiologia e Controle de Artrópodes Vetores (vigente até jan/2023).This research was primarily funded by the UK Medical Research Council, the Newton Fund and the Wellcome Trust through their join Zika Rapid Response scheme (Award number MC_PC_15086) and the United States Agency for International Development through its Combating Zika and Future Threats: A Grand Challenge for Development scheme (Award number AID-OAA-F16-00095).Nicodem J. Govella is supported by the African Research Leaders Award (Grant Ref: MR/T008873/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO) under the MRC/FCDO Concordat agreement, which is part of the EDCTP2 programme supported by the European Union.Gerry F. Killeen was partially supported by an AXA Research Chair award, jointly funded by the AXA Research Fund and the College of Science, Engineering and Food Sciences at University College Cork.Open access publication was funded and facilitated through the ongoing agreement between PLoS and the IReL consortium of Irish research libraries.The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Background: A low technology emanator device for slowly releasing vapour of the volatile pyrethroid transfluthrin was recently developed in Tanzania that provides robust protection against night biting Anopheles and Culex vectors of malaria and filariasis for several months. Here these same emanator devices were assessed in Dar es Salaam city, as a means of protection against outdoor-biting Aedes (Stegomia) aegypti, the most important vector of human arboviruses worldwide, in parallel with similar studies in Haiti and Brazil. Methods: A series of entomological experiments were conducted under field and semi-field conditions, to evaluate whether transfluthrin emanators protect against wild Ae. aegypti, and also compare the transfluthrin responsiveness of Ae. aegypti originating from wild-caught eggs to established pyrethroid-susceptible Ae. aegypti and Anopheles gambiae colonies. Preliminary measurements of transfluthrin vapour concentration in air samples collected near treated emanators were conducted by gas chromatography-mass spectrometry. Results: Two full field experiments with four different emanator designs and three different transfluthrin formulations consistently indicated negligible reduction of human landing rates by wild Ae. aegypti. Under semi-field conditions in large cages, 50 to 60% reductions of landing rates were observed, regardless of which transfluthrin dose, capture method, emanator placement position, or source of mosquitoes (mildly pyrethroid resistant wild caught Ae. aegypti or pyrethroid-susceptible colonies of Ae. aegypti and An. gambiae) was used. Air samples collected immediately downwind from an emanator treated with the highest transfluthrin dose (15g), contained 12 to 19 μg/m3 transfluthrin vapour. Conclusions: It appears unlikely that the moderate levels of pyrethroid resistance observed in wild Ae. aegypti can explain the modest-to-undetectable levels of protection exhibited. While potential inhalation exposure could be of concern for the highest (15g) dose evaluated, 3g of transfluthrin appears sufficient to achieve the modest levels of protection that were demonstrated entomologically. While the generally low levels of protection against Aedes reported here from Tanzania, and from similar entomological studies in Haiti and Brazil, are discouraging, complementary social science studies in Haiti and Brazil suggest end-users perceive valuable levels of protection against mosquitoes. It therefore remains unclear whether transfluthrin emanators have potential for protecting against Aedes vectors of important human arboviruses
In vitro antifungal activity of MMV Pathogen Box® compounds alone or in combination with antifungal drugs against mucormycosis agents
Full text linkMucormycosis is a severe fungal infection that demands immediate and decisive intervention upon suspicion. The causative agents of mucormycosis exhibit inherent resistance to echinocandins and voriconazole, and their in vitro susceptibility to terbinafine is highly variable and species-specific. Considering these factors and the limitations of currently available antifungal therapies, the identification of novel antifungals with potent activity against mucormycosis is of paramount importance. This study aims to identify compounds from the MMV
Pathogen Box® presenting antifungal activity against selected mucormycosis agents and to evaluate their potential synergistic effects when combined with antifungal drugs. A screening of the Pathogen Box® compounds was conducted, isolated or in combination with sub-inhibitory concentrations of amphotericin B, isavuconazole or posaconazole, against a Rhizopus oryzae strain. Hits from the screenings were further evaluated against eight Mucoralean strains for minimal inhibitory and fungicidal concentration determinations and to confirm synergistic interactions using the checkerboard method. Ultrastructural studies were performed using scanning electron microscopy. MMV675968 exhibited fungicidal activity against a R. oryzae strain. All but one Rhizopus spp. strains presented MIC ≤ 1 μg/mL, with a geometric mean of 0.78 μg/mL observed across all isolates for this compound, which did not change significantly the cellular structure of this fungus. The combination screening with antifungal drugs revealed six additional compounds potentially active against the R. oryzae strain, two of
them demonstrated proven synergism through the checkerboard assay. This first study with the MMV Pathogen Box® and Zigomycetes highlights promising new treatment options for mucormycosis in the future
The historical ecological background of West Nile virus in Portugal indicates one health opportunities
Full text linkProdução do Laboratório de Flavivírus (vigente até jan/2023).We acknowledge strategic funding from Fundação para a Ciência e a Tecnologia (FCT, IP) to cE3c and BioISI Research Unit (DOI: 10.54499/UIDB/00329/2020 and DOI: 10.54499/UIDB/04046/2020), the Portuguese Association of Researchers and Students in the UK (PARSUK) for providing a Bilateral Research Fund grant, and to the Associate Laboratory CHANGE (LA/P/0121/2020). Mónica V. Cunha also acknowledges institutional support from FCT (DOI: 10.54499/CEECINST/00032/2018/CP1523/CT0005).West Nile (WNV) is a zoonotic arbovirus with an expanding geographical range and epidemic activity in Europe. Not having yet experienced a human-associated epidemic, Portugal remains an outlier in the Mediterranean basin. In this study, we apply ecological niche modelling informed by WNV historical evidence and a multitude of environmental variables from across Portugal. We identify that ecological backgrounds compatible with WNV historical circulation are mostly restricted to the south, characterized by a warmer and drier climate, high avian diversity, specific avian species and land types. We estimate WNV ecological suitability across the country, identifying overlaps with the distributions of the three relevant hosts (humans, birds, equines) for public and animal health. From this, we propose a category-based spatial framework providing first of a kind valuable insights for WNV surveillance in Portugal under the One Health nexus. We forecast that near future climate trends alone will contribute to pushing adequate WNV ecological suitability northwards, towards regions with higher human density. This unique perspective on the past, present and future ecology of WNV addresses existing national knowledge gaps, enhances our understanding of the evolving emergence of WNV, and offers opportunities to prepare and respond to the first human-associated epidemic in Portugal
Ecological aspects of sand fly fauna (Diptera: Psychodidae, Phlebotominae) of Sumidouro District, State of Rio de Janeiro, Brazil
Full text linkAiming to compare and update the sand fly fauna of Portão de Pedra site, Sumidouro District, Rio de Janeiro State, Brazil, and considering the environmental changes occurred, the biology and ecology of the local sandfly species were examined five years later as a complementary study carried. Captures were made in the cave, surroundings of cave and forest of the region, from 6 p.m. to 6 a.m. Among the 2323 sandflies of eigth species of the Lutzomyia were captured: L. gasparviannai, L. edwardsi, L. tupynambai, L. hirsuta, L. whitmani, L. migonei, L. intermedia, Lutzomyia. sp and one species of the Brumptomyia Kind: B. brumpti. In 2009 and 2010 were collected 1756 samples from ten species of the former genus and two of the second. L. gasparviannai was predominant, in the three collection sites, in both periods. Five species implicated as vectors of Leishmania: L. intermedia, L. whitmani, L. migonei, L. hirsuta and L. davisi have been collected in the area. Poisson regression and ANOVA were used to perform statistical analysis of species most relevant. The record of L. intermedia and a case of American tegumentary leishmaniasis are relevant to the public health of municipality and of state of Rio de Janeiro
Entomological assessment of hessian fabric transfluthrin vapour emanators as a means to protect against outdoor-biting Aedes after providing them to households for routine use in Port-au-Prince, Haiti
Full text linkProdução científica do Laboratório de Fisiologia e Controle de Artrópodes Vetores (vigente até jan/2023).This research was primarily funded by the United States Agency for International Development through its Combating Zika and Future Threats: A Grand Challenge for Development scheme (Award number AID-OAA-F16-00095).Gerry F. Killeen was partially supported by an AXA Research Chair award, jointly funded by the AXA Research Fund and the College of Science, Engineering and Food Sciences at University College Cork.The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Open access publication was funded and facilitated through the ongoing agreement between PLoS and the IReL consortium of Irish research libraries.Background: A simple treated fabric device for passively emanating the volatile pyrethroid transfluthrin was recently developed in Tanzania that protected against nocturnal Anopheles and Culex mosquitoes for several months. Here these transfluthrin emanators were assessed in Port-au-Prince, Haiti against outdoor-biting Aedes. Methods: Transfluthrin emanators were distributed to participating households in poor-to-middle class urban neighbourhoods and evaluated once every two months in terms of their effects on human landing rates of wild Aedes populations. A series of three such entomological assessment experiments were conducted, to examine the influence of changing weather conditions, various transfluthrin formulations and emanator placement on protective efficacy measurements. Laboratory experiments assessed resistance of local Aedes aegypti to transfluthrin and deltamethrin, and the irritancy and repellency of the transfluthrin-treated fabric used in the field. Results: Across all three entomological field assessments, little evidence of protection against wild Ae. aegypti was observed, regardless of weather conditions, transfluthrin formulation or emanator placement: A generalized linear mixed model fitted to the pooled data from all three assessment rounds (921 females caught over 5129 hours) estimated a relative landing rate [95% Confidence interval] of 0.87 [0.73, 1.04] for users of treated versus untreated emanators (P = 0.1241). Wild Ae. aegypti in this setting were clearly resistant to transfluthrin when compared to a fully susceptible colony. Conclusions: Transfluthrin emanators had little if any apparent effect upon Aedes landing rates by wild Ae. aegypti in urban Haiti, and similar results have been obtained by comparable studies in Tanzania, Brazil and Peru. In stark contrast, however, parallel sociological assessments of perspectives among these same end-users in urban Haitian communities indicate strong satisfaction in terms of perceived protection against mosquitoes. It remains unclear why the results obtained from these complementary entomological and sociological assessments in Haiti differ so much, as do those from a similar set of studies in Brazil. It is encouraging, however, that similar contrasts between the entomological and epidemiological results of a recent large-scale assessment of another transfluthrin emanator product in Peru, which indicate they provide useful protection against Aedes-borne arboviral infections, despite apparently providing only modest protection against Aedes mosquito bites
Clinical profile and parameters of patients monoinfected with HBV and infected with HDV in Western Amazon
Full text linkProdução científica do Laboratório de Hepatites Virais.This study was financed by the Foundation Oswaldo Cruz of Rondônia - FIOCRUZ/RO, Fundação Rondônia de Amparo ao Desenvolvimento das Ações Científicas e Tecnológicas and Pesquisa do Estado de Rondônia - FAPERO (Chamada 001/2020 Programa Pesquisa para o SUS Processo nº 0012.259726/1020-70; Process: VPPIS-003-FIO-20-2-75 - INOVAÇÃO NA AMAZONIA).Background: Hepatitis Delta represents a greater risk in the progression of advanced liver disease and HCC compared with HBV. The exact mechanism that determines the spontaneous clearance of delta virus or its progression to cirrhosis remains unknown. Therefore, this study aimed to analyze the clinical profile of HBV and HBV/HDV individuals in the Western Amazon. Methods: The study was carried out at the Specialized Outpatient Clinic for Viral Hepatitis belonging to the Centro de Pesquisa em Medicina Tropical de Rondônia/CEPEM. 100 individuals were included, stratified into two groups: 50 with hepatitis B virus and 50 with hepatitis Delta virus. Results: The overall mean age was 48 years. For the HBV and HDV groups, 66 % (33/50) and 54 % (27/50) were men and 56 % (28/50) and 58 % (29/50) were on antiviral treatment, respectively. Patients with detectable HDV-RNA demonstrated high levels of ALT and AST compared to individuals with undetectable HDV-RNA. Comparative analysis between HBV carriers and infected with HDV shows significant differences in terms of age, HBV-DNA levels, albumin, hepatomegaly and splenomegaly. Conclusion: Several markers were important for differentiating HBV and HDV infections. HDVRNA detectable showed significant changes in biomarkers compared to undetectable patients, suggesting a possible worse prognostic effect in this group
Helminth community of Nectomys squamipes naturally infected by Schistosoma mansoni in an endemic area in Brazil: a comparison of 22 years apart
Full text linkProdução científica do Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios.This project was financially supported by the National Council for Scientific and Technological Development (CNPq), Brazil [315844/2023-0], Oswaldo Cruz Institute (IOC, FIOCRUZ), the Carlos Chagas Filho Foundation for Research Support in Rio de Janeiro, Brazil [E− 26/010.001597/2019 and E− 26/210.194/2019], and the Postgraduate Program on Parasite Biology (IOC-FIOCRUZ).Karina Varella Arpon received grants from the Coordination Office for Improvement of Higher-Education Personnel (CAPES), Brazil, under finance code 001.Rosana Gentile received a researcher fellowship from CNPq [303643/2022-6].Arnaldo Maldonado Júnior received a researcher fellowship from CNPq [315844/2023-0].The municipality of Sumidouro in the state of Rio de Janeiro, southeastern Brazil, is considered an area with low endemicity of Schistosoma mansoni. In this municipality, the wild water rat Nectomys squamipes is a wild reservoir of S. mansoni. A helminth community survey was carried out on N. squamipes populations in Sumidouro from 1997 to 1999. In the present study, we compared the helminth fauna and the helminth community structure of N. squamipes with a recent survey after a 22-year time interval, considering that the prevalence of S. mansoni infection in humans remained stable and that the area showed the same environmental characteristics. Seventythree host specimens of N. squamipes collected between 1997 and 1999 and 21 specimens collected in 2021 were analyzed in this study. Seven helminth species were found in each collection period. The nematode Syphacia evaginata was recorded for the first time in N. squamipes in 2021. Syphacia venteli was the most abundant species in both periods and the most prevalent in 2021. During the period from 1997 to 1999, the most prevalent species was Hassalstrongylus epsilon. Significant differences in prevalence and abundance in relation to host sex were observed only for S. mansoni in 1997–1999. Significant differences in the abundance of the helminth species over time were observed only in Physaloptera bispiculata. Hassalstrongylus epsilon, S. venteli and S. mansoni were the dominant species in both periods. Litomosoides chagasfilhoi, Echinostoma paraensei paraensei and P. bispiculata became dominant, codominant and subordinate, respectively, over time. In conclusion, the helminth community of N. squamipes remained stable, with similar species richness, prevalence and abundance values and low betadiversity over time. The occurrence of S. mansoni in the water rat has remained stable for decades, highlighting its importance for schistosomiasis control
Avaliação de polimorfismos de único nucleotídeo e expressão do gene SOCS5 em pacientes com Carcinoma Hepatocelular (CHC)
Full text linkO Carcinoma Hepatocelular (CHC) é a forma mais comum de câncer primário do fígado, caracterizado por um diagnóstico geralmente tardio. Assim, estudos que identifiquem biomarcadores que auxiliem no diagnóstico precoce de tumores são necessários, como os que destacam a relação do gene SOCS5 na tumorigênese do CHC. Desse modo, o objetivo do estudo foi avaliar os polimorfismos de único nucleotídeo e expressão gênica do gene SOCS5 em pacientes com Carcinoma Hepatocelular (CHC). Este estudo transversal foi realizado com a comparação dos grupos CHC e cirrótico, ambos com diagnóstico confirmado. O DNA analisado foi extraído de amostras de sangue periférico, já o RNA total foi extraído a partir de células mononucleares do sangue periférico (PBMC), sendo o material genético submetido às metodologias de RT-PCR, sequenciamento de Sanger e qPCR para análise de polimorfismos presentes no gene e diferenças da expressão gênica relativa, respectivamente. Para as análises do sequenciamento foram utilizadas as ferramentas BioEdit e Geneious, foram executados ensaios de genotipagem e expressão gênica, sendo realizadas análises de correlação, sobrevida e regressão logística, admitindo para todas análises o nível de significância fixado em p≤ 0,05. Foram encontrados quatro polimorfismos na região gênica do SOCS5, com destaque para o rs6738426, que se apresentou de forma semelhantes entre os grupos analisados. Em relação à expressão do gene, foi observado que pacientes cirróticos com classificação Child-Pugh A apresentaram maiores níveis de SOCS5, indicando que, possivelmente nesse grupo, o gene apresenta um papel supressor de tumor, provavelmente por meio do feedback negativo das vias JAK/STAT. Já nos pacientes com CHC, foi verificada uma menor sobrevida naqueles com níveis elevados de expressão de SOCS5, indicando um papel tumorigênico, provavelmente devido ao feedback positivo da via PI3K/Akt/mTOR. Na análise multivariada, a susceptibilidade ao CHC foi associada à idade [p= 0,003 OR 0,924 IC (0,877-0,9740)] e aos níveis de HDL [(p= 0,043 OR 1,032 IC (1,001 – 1,065)], sendo o aumento da idade e a diminuição do HDL considerados fatores de risco. Deste modo, propõe-se que o gene SOCS5 pode desempenhar um importante papel no processo tumorigênico, podendo atuar de forma oncogênica ou antitumorigênica. No entanto, estudos com coorte maior de amostras são indicados para validar os resultados aqui encontrados, assim como a análise do impacto do SOCS5 dentro das vias JAK/STAT e PI3K/Akt/ mTOR, por meio de ensaios de silenciamento e superexpressão do gene.Hepatocellular Carcinoma (HCC) is the most common type of primary liver cancer, characterized by a typically late diagnosis. Therefore, studies identifying biomarkers that may help in early diagnosis of tumors are necessary, such as those highlighting the relationship of the SOCS5 gene in HCC tumorigenesis. Thus, the aim of the study was to evaluate single nucleotide polymorphisms and gene expression of the SOCS5 gene in patients with HCC. This cross-sectional study was conducted by comparing HCC and cirrhotic groups, both with confirmed diagnoses. The analyzed DNA was extracted from peripheral blood samples, while total RNA was extracted from peripheral blood mononuclear cells (PBMC), and the genetic material was subjected to RT-PCR, Sanger sequencing, and qPCR methodologies for the analysis of gene polymorphisms and relative gene expression differences, respectively. For sequencing analyses, the BioEdit and Geneious tools were used, genotyping and gene expression assays were performed, and correlation, survival and logistic regression analyzes were carried out, allowing for all analyzes the level of significance set at p≤ 0.05. Four polymorphisms were found in the SOCS5 gene region, with emphasis on rs6738426, which showed similar occurrences between the analyzed groups. Regarding gene expression, it was observed that cirrhotic patients with Child-Pugh A classification exhibited higher levels of SOCS5, indicating that in this group, the gene may play a tumor-suppressive role, possibly through negative feedback of the JAK/STAT pathways. In HCC patients, a lower survival rate was observed in those with elevated levels of SOCS5 expression, suggesting a tumorigenic role, likely due to positive feedback from the PI3K/Akt/mTOR pathway. In multivariate analysis, susceptibility to HCC was associated with age [p= 0.003, OR 0.924, CI (0.877-0.9740)] and HDL levels [p= 0.043, OR 1.032, CI (1.001 – 1.065)], with increased age and decreased HDL considered risk factors. Thus, it is proposed that the SOCS5 gene may play a significant role in the tumorigenic process, potentially acting in an oncogenic or antitumorigenic manner. However, larger cohort studies are recommended to validate the results found here, as well as the analysis of the impact of SOCS5 within the JAK/STAT and PI3K/Akt/mTOR pathways through gene silencing and overexpression assays.2025-05-0
Avaliação da dinâmica de coinfecção e superinfecção pelos arbovírus Chikungunya e Mayaro em uma população de Aedes aegypti de laboratório
Full text linkA emergência e reemergência de arbovírus são eventos associados a graves crises na saúde pública, muitas vezes caracterizadas pela presença simultânea de diferentes patógenos em uma mesma região, como o ocorrido no Brasil durante a tríplice epidemia de Dengue (DENV), Zika (ZIKV) e Chikungunya (CHIKV) em 2015-2016. Dentro desse atual panorama de cocirculação arboviral, o vírus Mayaro (MAYV) tem sido apontado como um potencial emergente no ambiente urbano devido a fatores como a notificação de casos de infecções por MAYV nessas regiões, junto com a ampla circulação de potenciais vetores e a presença de hospedeiros suscetíveis. Assim, a consequência da entrada de um novo vírus, como MAYV, no ambiente urbano brasileiro pode gerar um cenário epidemiológico preocupante, especialmente devido à subnotificação de seus casos de infecções por MAYV, decorrente da semelhança clínica com o CHIKV. Desta forma, o objetivo do presente estudo foi avaliar a dinâmica de coinfecção (infecção do mosquito por mais de um vírus em um mesmo repasto sanguíneo) e superinfecção (infecção do mosquito por mais de um vírus em sucessivos repastos sanguíneos) por CHIKV e MAYV em Aedes aegypti de laboratório. Para isso, foram conduzidos experimentos de coinfecção envolvendo MAYV e CHIKV, bem como experimentos de superinfecção, tanto por MAYV quanto por CHIKV, por meio de infecções orais em mosquitos. As taxas de infecção (TI), disseminação (TD) e transmissão (TT) de ambos os vírus foram determinadas por RT-qPCR a partir da coleta e subsequente extração de RNA das amostras individuais de intestino, carcaça e saliva. Adicionalmente, a presença dos vírus na progênie das fêmeas infectadas oralmente nos ensaios de coinfecção e superinfecção também foi avaliada por RT-qPCR. O principal resultado do trabalho mostrou que CHIKV e MAYV podem ser transmitidos simultaneamente por Ae. aegypti em cenários de coinfecção, enquanto que em situações de superinfecção tanto por MAYV quanto por CHIKV, uma primeira infecção afeta a capacidade de transmissão do vírus adquirido posteriormente, evidenciando a ocorrência de interferência de replicação entre os vírus. Em relação à análise de transmissão vertical, não foram encontradas amostras positivas em nenhum dos grupos testados. Tais constatações têm implicações importantes para o planejamento de ações de saúde pública no país, enfatizando cenários complexos de cocirculação de arbovírus e os riscos epidemiológicos associados.The emergence and re-emergence of arboviruses are events associated with serious public health crises, often characterized by the simultaneous presence of different pathogens in the same region, such as what occurred in Brazil during the triple epidemics of Dengue (DENV), Zika (ZIKV) and Chikungunya (CHIKV) in 2015-2016. Within this current panorama of arboviral cocirculation, the Mayaro virus (MAYV) has been identified as an emerging potential in the urban region due to factors such as the notification of cases of MAYV infections in these regions, along with the wide circulation of potential vectors and the presence of susceptible hosts. Thus, the consequence of the entry of a new virus, such as MAYV, into the Brazilian urban area can generate a worrying epidemiological scenario, especially due to the underreporting of cases of MAYV infections, due to its clinical similarity with CHIKV. Therefore, the objective of the present study was to evaluate the dynamics of coinfection (mosquito infection by more than one virus in the same blood meal) and superinfection (mosquito infection by more than one virus in successive blood meals) by CHIKV and MAYV in Aedes aegypti colony. To this end, coinfection experiments involving MAYV and CHIKV were conducted, as well as superinfection experiments, both by MAYV and CHIKV, through oral infections in mosquitoes. The infection (IR), dissemination (DR) and transmission (TR) rates of both viruses were determined by qRT-PCR from the collection and subsequent extraction of RNA from individual intestine, carcass and saliva samples. Additionally, the presence of viruses in the progeny of orally infected females in coinfection and superinfection assays was also evaluated by qRT-PCR. The main result of the work showed that CHIKV and MAYV can be transmitted simultaneously by Ae. aegypti in coinfection scenarios, while in situations of superinfection by both MAYV and CHIKV, a first infection affects the transmission capacity of the subsequently acquired virus, demonstrating the occurrence of replication interference between the viruses. Regarding vertical transmission analysis, no positive samples were found in any of the tested groups. Such findings have important implications for the planning of public health actions in the country, emphasizing complex arbovirus cocirculation scenarios and the associated epidemiological risks