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Dengue and Zika virus infection patterns vary among Aedes aegypti field populations from Belo Horizonte, a Brazilian endemic city
No full textDengue virus (DENV) and Zika virus (ZIKV) belong to the same viral family, the Flaviviridae. They cause recurring threats to the public health systems of tropical countries such as Brazil. The primary Brazilian vector of both viruses is the mosquito Aedes aegypti. After the mosquito ingests a blood meal from an infected person, the viruses infect and replicate in the midgut, disseminate to secondary tissues and reach the salivary gland (SG), where they are ready to be transmitted to a vertebrate host. It is thought that the intrinsic discrepancies among mosquitoes could affect their ability to deal with viral infections. This study confirms that the DENV and ZIKV infection patterns of nine Ae. aegypti field populations found in geographically separate health districts of an endemic Brazilian city vary. We analyzed the infection rate, disseminated infection, vector competence, and viral load through quantitative PCR. Mosquitoes were challenged using the membrane-feeding assay technique and were tested seven and fourteen days post-infection (early and late infection phases, respectively). The infection responses varied among the Ae. aegypti populations for both flaviviruses in the two infection phases. There was no similarity between DENV and ZIKV vector competencies or viral loads. According to the results of our study, the risk of viral transmission overtime after infection either increases or remains unaltered in ZIKV infected vectors. However, the risk may increase, decrease, or remain unaltered in DENV-infected vectors depending on the mosquito population. For both flaviviruses, the viral load persisted in the body even until the late infection phase. In contrast to DENV, the ZIKV accumulated in the SG over time in all the mosquito populations. These findings are novel and may help direct the development of control strategies to fight dengue and Zika outbreaks in endemic regions, and provide a warning about the importance of understanding mosquito responses to arboviral infection
Informativo nr. 147
No full textBoletim informativo desenvolvido pelo Nethis/Fiocruz Brasília com os principais eventos e notícias. Edição publicada no dia 15/06/2021
Diversidade de mosquitos (Diptera: Culicidae) com ênfase na fauna de importância epidemiológica da área do Parque Nacional da Serra dos Órgãos, Estado do Rio de Janeiro, Brasil
No full textO inventário faunístico de mosquitos em áreas de ambiente natural é de considerável importância em estudos ecológicos. As populações naturais de animais em uma determinada área biogeográfica distribuem-se em comunidades ecologicamente estáveis, ocorrendo de forma não estática, estando o seu inter-relacionamento sujeito a constantes flutuações em resposta ao ambiente. O conhecimento da diversidade de insetos na Mata Atlântica é muito importante para avaliações das mudanças no padrão das atividades de suas populações, até então considerados como de hábito preferencialmente silvestre. Frequentemente, espécies de grupos de insetos que apresentam hábitos tipicamente silvestres adaptam-se a criadouros localizados em áreas urbanas e, por conseguinte, à convivência com o homem. Tendo em vista nesse cenário, este estudo teve o objetivo principal de contribuir com o conhecimento da diversidade e calcular indicadores ecológicos para as espécies, comparando também os dados entre os pontos amostrais com ênfase na fauna de importância epidemiológica da área do Parque Nacional da Serra dos Órgãos, Estado do Rio de Janeiro, Brasil. Foram realizadas sete campanhas de campo com duração de três dias consecutivos, sendo estabelecidos pontos amostrais com diferentes características de vegetação e foram efetuadas coletas de formas adultas e imaturas. As capturas dos espécimes adultos foram realizadas com o auxílio de armadilha luminosa de Shannon, no crepúsculo vespertino, e com armadilhas tipo CDC com CO², instaladas por 24 horas, tendo substituição do recipiente coletor a cada quatro horas, incluindo os crepúsculos, método da busca ativa no período vespertino As coletas de formas imaturas foram realizadas com a utilização de conchas entomológicas, sifão manual em bromélias, entrenós de bambu e armadilhas de oviposição do tipo ovitrampa para coleta de ovos. Para avaliar e comparar a diversidade das populações de mosquitos em cada sítio amostral foram realizados: Dendrograma de similaridade, Análise de Correspondência Canônica, Diversidade de Shannon, o Índice de Equabilidade de Pielou o Teste T unilateral. Foi possível observar que Culex iridescens apresentou a maior abundância totalizando 27%, seguida de Limatus durhamii 12%. Trichoprosopon pallidiventer 9%, Culex spinosus 6%, Haemagogus leucocelaenus 8%. A ovitrampa foi a ferramenta de monitoramento que apresentou a maior riqueza de espécies, contudo, o índice de diversidade não foi tão elevado, sendo o quarto maior quando comparado com os demais criadouros. Já a armadilha de CDC com CO², foi a que apresentou a segunda maior riqueza, com 16 espécies capturadas. Destacamos a presença de Aedes scapularis, Haemagogus leucocelaenus e Limatus durhamii vetores de agentes etiológicos. Os estudos nessa unidade de preservação fornecem informações sobre a diversidade e, consequentemente, subsídios para a compreensão de aspectos epidemiológicos de espécies vetoras potenciais de patógenosThe faunal inventory of mosquitoes in areas of natural environment is of considerable importance in ecological studies. The natural populations of animals in each biogeographic area are distributed in ecologically stable communities, occurring in a dynamic way, and their interrelationship is subject to constant fluctuations in response to the environment. The knowledge of the diversity of insects in the Atlantic Forest is particularly important for evaluating changes in the pattern of activities of their populations, which until now were considered to have a preferentially wild habit. Often species of groups of insects that have typically wild habits adapt to breeding sites located in urban areas and, therefore, to coexistence with humans. In view of this scenario, this study had the main objective of contributing to knowledge regarding the diversity and calculating ecological indicators for mosquito species, also comparing the data between the sampling points with an emphasis on fauna of epidemiological importance in the Serra dos Órgãos National Park area, State of Rio de Janeiro, Brazil To assess and compare the diversity of mosquito populations at each sampling site, the Similarity Dendrogram, Canonical Correspondence Analysis, Shannon Diversity, Pielou's Equability Index and One-sided T Test indices were used. It was possible to observe that Culex iridescens had the highest abundance with a total of 27%, followed by Limathus durhamii 12%, Trichoprosopon pallidiventer 9%, Culex spinosus 6% and Haemagogus leucocelaenus 8%. The ovitrap was the monitoring tool that presented the greatest species richness; however, the diversity index was not as high, being the fourth largest when compared to other breeding sites. The CDC trap with CO2, on the other hand, presented the second highest richness, with 16 species captured. We highlight the presence of Aedes scapularis, Haemagogus leucocelaenus and Limatus durhamii vectors of etiological agent
Composition and structure of the helminth community of rodents in matrix habitat areas of the Atlantic forest of southeastern Brazil
No full textThe predominant landscape of the Atlantic Forest of the Brazilian state of Rio de Janeiro is made up of forest fragments surrounded by a matrix of modified habitat, which may influence the occurrence and distribution of host species and their parasites in comparison with the original continuous forest. The present study describes the structure, composition, and diversity of the helminth community found in rodents in two areas of an open matrix of different status of conservation. The abundance, intensity, and prevalence were calculated for each helminth species in rodent species. The influence of biotic and abiotic factors on the abundance and prevalence of the helminth species was also investigated. Community structure was analyzed based on the beta diversity and a bipartite network. Nine helminth species were recovered from Akodon cursor, Necromys lasiurus and Mus mus-culus, with the greatest helminth species richness being recorded in A. cursor (S =8), followed by N. lasiurus (S =6), and M. musculus (S =3). Only three of the helminths recorded in A. cursor had been recorded previously in this rodent in the Atlantic Forest, where 12 different helminths have been recorded, so that the other five are new occurrences for this rodent. All the helminth species of N. lasiurus had been reported previously in this rodent in the Cerrado and Caatinga regions. Mus musculus was infected with the same helminths as the local fauna. Host species and locality were the most important factors influencing helminth abundance and prevalence. Beta- diversity was high for infracommunities indicating more substitutions of helminth species than losses among individuals. Three helminths species were shared by the three host species. The reduced beta-diversity observed in the component communities was consistent with the overlap observed in the helminth fauna of the host species
Princípios Básicos de Cultivo Celular: Biologia Básica das Células
No full textdubladodubladodubladodubladoCuradoria e supervisão de Alessandra Melo de AguiardubladodubladodubladoAprendizado sobre os princípios básicos do cultivo celular dentro do contexto da biologia celularFiocruzMP4Tópicos em cultura de células de mamíferosPrograma de Pós-Graduação em Biociências e Biotecnologi
Cestode and nematode larvae of hygienic-sanitary importance parasitizing Percophis brasiliensis (Actinopterygii) collected from fish markets of the municipality of Niterói, RJ, Brazil
No full textPercophis brasiliensis is a fish species appreciated as a fried appetizer at beachside kiosks of Niterói, state of Rio de Janeiro,
Brazil. The constant presence of helminth larvae in the viscera and serosa of individuals of the species has been the subject of
complaints among local fish traders because of economic losses due to their repugnant aspect. Considering their hygienic-sanitary
importance and significance for collective health, the presence of helminth larvae was investigated in 64 individual fish of
P. brasiliensis purchased from Niterói fish markets in 2019. Cestodes, identified as larvae of Grillotia carvajalregorum, were
found parasitizing the serosa of the stomach, mesentery and abdominal cavity. Nematodes, identified as third-instar larvae of
Contracaecum sp., Terranova sp., Hysterothylacium deardorffoverstreetorum, H. fortalezae and Raphidascaris sp., were found
parasitizing the stomach, intestine, liver, gonads, stomach serosa, mesentery and abdominal cavity. The highest parasitic
indices were for G. carvajalregorum and H. deardorffoverstreetorum, with prevalences of 100% and 81.25%, mean intensities
of 8.05 and 8.13, mean abundances of 8.05 and 6.61 and infection ranges of 1–131 and 1–42 specimens per host, respectively.
Considerations about the zoonotic potential and hygienic-sanitary significance of these parasites are presented in order to
increase food safety for consumers
On the analysis of mortality risk factors for hospitalized COVID-19 patients: A data-driven study using the major Brazilian database
No full textBackground: Brazil became the epicenter of the COVID-19 epidemic in a brief period of a few months after the first officially registered case. The knowledge of the epidemiological/clinical profile and the risk factors of Brazilian COVID-19 patients can assist in the decision making of physicians in the implementation of early and most appropriate measures for poor prognosis patients. However, these reports are missing. Here we present a comprehensive study that addresses this demand.
Methods: This data-driven study was based on the Brazilian Ministry of Health Database (SIVEP-Gripe) regarding notified cases of hospitalized COVID-19 patients during the period from February 26th to August 10th, 2020. Demographic data, clinical symptoms, comorbidities and other additional information of patients were analyzed.
Results: The hospitalization rate was higher for male gender (56.56%) and for older age patients of both sexes. Overall, the lethality rate was quite high (41.28%) among hospitalized patients, especially those over 60 years of age. Most prevalent symptoms were cough, dyspnoea, fever, low oxygen saturation and respiratory distress. Cardiac disease, diabetes, obesity, kidney disease, neurological disease, and pneumopathy were the most prevalent comorbidities. A high prevalence of hospitalized COVID-19 patients with cardiac disease (65.7%) and diabetes (53.55%) and with a high lethality rate of around 50% was observed. The intensive care unit (ICU) admission rate was 39.37% and of these 62.4% died. 24.4% of patients required invasive mechanical ventilation (IMV), with high mortality among them (82.98%). The main mortality risk predictors were older age and IMV requirement. In addition, socioeconomic conditions have been shown to significantly influence the disease outcome, regardless of age and comorbidities.
Conclusion: Our study provides a comprehensive overview of the hospitalized Brazilian COVID-19 patients profile and the mortality risk factors. The analysis also evidenced that the disease outcome is influenced by multiple factors, as unequally affects different segments of population
Phenotypic and Functional Signatures of Peripheral Blood and Spleen Compartments of Cynomolgus Macaques Infected With T. cruzi: Associations With Cardiac Histopathological Characteristics
No full textWe performed a detailed analysis of immunophenotypic features of circulating leukocytes and spleen cells from cynomolgus macaques that had been naturally infected with Trypanosoma cruzi, identifying their unique and shared characteristics in relation to cardiac histopathological lesion status. T. cruzi-infected macaques were categorized into three groups: asymptomatic [CCC(-)], with mild chronic chagasic cardiopathy [CCC(+)], or with moderate chronic chagasic cardiopathy [CCC(++)]. Our findings demonstrated significant differences in innate and adaptive immunity cells of the peripheral blood and spleen compartments, by comparison with non-infected controls. CCC(+) and CCC(++) hosts exhibited decreased frequencies of monocytes, NK and NKT-cell subsets in both compartments, and increased frequencies of activated CD8+ T-cells and GranA+/GranB+ cells. While a balanced cytokine profile (TNF/IL-10) was observed in peripheral blood of CCC(-) macaques, a predominant pro-inflammatory profile (increased levels of TNF and IFN/IL-10) was observed in both CCC(+) and CCC(++) subgroups. Our data demonstrated that cardiac histopathological features of T. cruzi-infected cynomolgus macaques are associated with perturbations of the immune system similarly to those observed in chagasic humans. These results provide further support for the validity of the cynomolgus macaque model for pre-clinical research on Chagas disease, and provide insights pertaining to the underlying immunological mechanisms involved in the progression of cardiac Chagas diseas
Incidence of thyroid diseases: Results from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)
No full textObjective: To evaluate incidence of subclinical and overt hyperthyroidism and hypothyroidism. Subjects
and methods: The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a prospective cohort study
of 15,105 civil servants, examined at baseline and over a 4-year follow-up. This analysis included 9,705
participants with normal thyroid function at baseline, follow-up information about thyroid function and
with no report of using drugs that may interfere in the thyroid function. Thyroid function was defined by
TSH/FT4 levels or routine use of thyroid hormones/anti-thyroid medications. Annual and cumulative (over
4-year) incidence rates were presented as percentages (95% Confidence Intervals). Results: The incidence
of all overt and subclinical thyroid disease was 6.7% (1.73%/year): 0.19% for overt hyperthyroidism (0.048%/
year), 0.54% for subclinical hyperthyroidism (0.14%/year), 1.98% for overt hypothyroidism (0.51%/year),
and 3.99% for subclinical hypothyroidism (1.03%/year). The incidence of all thyroid diseases was higher in
women, when compared to men, with a low women:men ratio (1.36). For Blacks the highest incidence was
for overt hyperthyroidism, while for Whites, the highest incidence was for overt hypothyroidism. However,
the highest incidence of overt hyperthyroidism was detected in Asian descendants. The presence of
antithyroperoxidase antibodies at baseline was associated with higher incidence of overt thyroid diseases.
Conclusions: These results showed a high incidence of hypothyroidism, which is compatible with a
country with a more-than-adequate iodine intake. The low women:men ratio of the incidence of thyroid
dysfunction highlights the importance of the diagnosis of thyroid diseases among men in Brazil
Princípios Básicos de Cultivo Celular: sistema de cultivo celular
No full textdubladoVídeo sobre os princípios básicos de cultivo celular, apresentando a sub-temática: Sistema de cultivo celularFiocruzMP4Tópicos em Cultura de Células de MamíferosPrograma de Pós-Graduação em Biociências e Biotecnologi