Publications by authors named "Claudia Nunes Duarte dos Santos"

Article Synopsis
  • Oropouche virus (OROV) is an arbovirus that has spread beyond its usual Amazon basin habitat, with a significant outbreak occurring in the Brazilian Amazon during 2023-24, leading to cases in other Latin American countries.
  • A genomic and epidemiological study from January 2023 to July 2024 showed a higher incidence of OROV in smaller municipalities, and a correlation between agricultural area sizes, particularly banana and cassava plantations, and the number of OROV cases.
  • Phylogenetic analysis indicated multiple exportation events of a new reassortant lineage of OROV from Amazon regions to other parts of Brazil occurred between January and March 2024.
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Background: The immunological response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and immunisation is variable.

Objectives: To describe the humoral immune response by correlating IgA and IgG antibodies with NAbs titration following CoronaVac® immunisation and an mRNA (Comirnaty®) booster among healthcare workers (HCWs) and to compare the cytokine and interleukin profiles between HCWs vaccinated with CoronaVac and coronavirus disease 2019 (COVID-19) infected patients.

Methods: Samples from 133 HCWs collected at 20 (T1) and 90 (T2) days after CoronaVac immunisation and 15 (T3) days after a booster dose with the Comirnaty vaccine were analysed for IgA and IgG EIA and neutralisation assay.

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Article Synopsis
  • * The lack of epidemics may be due to recent human presence, limited domestication of local species, and past immigration that introduced other viruses, making spillovers less likely.
  • * However, recent large-scale deforestation and environmental changes could temporarily hinder virus emergence, but health authorities should be aware of the potential long-term risks from urbanization and climate change.
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Orthobunyavirus oropouche ense virus (OROV), the causative agent of Oropouche fever, is widely dispersed in Brazil and South America, causing sporadic outbreaks. Due to the similarity of initial clinical symptoms caused by OROV with other arboviruses found in overlapping geographical areas, differential diagnosis is challenging. As for most neglected tropical diseases, there is a shortage of reagents for diagnosing and studying OROV pathogenesis.

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Viruses from the Flaviviridae family, such as Dengue virus (DENV), Yellow fever virus (YFV), and Zika virus (ZIKV) are notorious global public health problems. ZIKV emergence in Polynesia and the Americas from 2013 to 2016 raised concerns as new distinguishing features set it apart from previous outbreaks, including its association with neurological complications and heightened disease severity. Virus detection is impaired as cross-reactivity to other closely related orthoflaviviruses is common among commercially available diagnostic kits.

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Article Synopsis
  • - Dengue virus serotype 2, genotype Cosmopolitan (DENV-2-GII), is widely distributed and was newly identified in Brazil, having been present in other regions since 2019.
  • - A study sequenced 237 confirmed DENV-2 cases from March 2021 to March 2023, discovering that DENV-2-GII circulates in all areas of Brazil, having been introduced multiple times between 2020 and 2022.
  • - Despite its presence, DENV-1 dominated the Brazilian dengue epidemic in 2022, suggesting pre-existing immunity from prior DENV-2-GIII infections may limit symptomatic cases of DENV-2-GII, highlighting the need for ongoing
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The pathogenesis of (DENV) infection is complex and involves viral replication that may trigger an inflammatory response leading to severe disease. Here, we investigated the correlation between viremia and cytokine levels in the serum of DENV-infected patients. Between 2013 and 2014, 138 patients with a diagnosis of acute-phase DENV infection and 22 patients with a non-dengue acute febrile illness (AFI) were enrolled.

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Article Synopsis
  • * Researchers utilized phylogenetic and epidemiological models to map YFV transmission patterns over different epidemic seasons and identified areas of high infection risk linked to low vaccination rates in major urban centers.
  • * By analyzing the genomic data, the study revealed three distinct YFV lineages and demonstrated the connectivity between the endemic North and the extra-Amazonian region, suggesting that genomics combined with eco-epidemiology can enhance understanding and strategies for controlling the virus.
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Article Synopsis
  • * Collaborative efforts led to the collection of 422 chikungunya virus genomes from 12 states, offering insights into how the virus has spread and evolved across the country.
  • * Analysis of the genetic data revealed two distinct subclades of the virus and highlighted Northeast Brazil as the main spreading region, with immune system factors potentially influencing its genetic diversity.
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Article Synopsis
  • Mosquito-borne diseases like Yellow Fever, Zika, Chikungunya, and Dengue are causing big health problems in Brazil, especially since Chikungunya started spreading in 2014.
  • In two years (2021-2022), scientists created 422 new virus genomes from 12 states to better understand how Chikungunya spreads, as there were over 312,000 reported cases.
  • They discovered that the northeast region of Brazil is the main area where the virus is spreading to other places and found that certain factors in the immune system might be changing the virus's genes in Brazil.
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and are considered the most important vectors of arboviruses in the world. is the primary vector of dengue, urban yellow fever, chikungunya and zika in Brazil, and is considered a potential vector. Distribution patterns and the influence of climatic variables on the oviposition of and were evaluated in Morretes, a tourist city in the coastal area of Paraná State, Brazil, which has recently been experiencing cases of dengue fever.

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Mayaro virus is an emerging arbovirus that causes nonspecific febrile illness or arthralgia syndromes similar to the Chikungunya virus, a virus closely related from the family. MAYV outbreaks occur more frequently in the northern and central-western states of Brazil; however, in recent years, virus circulation has been spreading to other regions. Due to the undifferentiated initial clinical symptoms between MAYV and other endemic pathogenic arboviruses with geographic overlapping, identification of patients infected by MAYV might be underreported.

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The emergence of the (ZIKV) has highlighted the need for a deeper understanding of virus-host interactions in order to pave the way for the development of antiviral therapies. The present work aimed to address the response of neutrophils during ZIKV infection. Neutrophils are important effector cells in innate immunity implicated in the host's response to neurotropic arboviruses.

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Vaccination is a current strategy used to prevent infections in patients with immune-mediated rheumatic diseases. However, the use of live-attenuated vaccines prepared from living microorganisms in these patients should be avoided due to the risk of acquiring infections. The present study aimed to investigate the effect of the yellow fever (YF) vaccine (a live-attenuated vaccine) in 12 patients with rheumatoid arthritis (RA).

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Article Synopsis
  • Zika virus (ZIKV) is mostly spread to people by mosquitoes and wasn’t a big deal until outbreaks happened in places like Yap Island and Brazil.
  • Most people who get ZIKV don't feel sick, but in some cases, it can cause serious problems for babies and adults, leading to issues like small heads in infants and nerve problems in adults.
  • Scientists are looking into natural compounds called flavonoids as possible treatments or vaccines for ZIKV since they're safe for humans, but more research is needed to know if they can really help.
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Zika virus (ZIKV) caused global concern due to Brazil's unexpected epidemic, and it was associated with congenital microcephaly and other gestational intercurrences. The study aimed to analyze the placenta morphometric changes of ZIKV-infected pregnant women (ZIKV group; n = 23) compared to placentas of HIV-infected (HIV group; n = 24) and healthy pregnant women (N-control group; n = 22). It also analyzed the relationship between the morphometric results and pathological alterations on conventional microscopy, gestational trimester of infection, and presence of the congenital Zika syndrome (CZS).

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Objectives: Screening for genes differentially expressed in placental tissues, aiming to identify transcriptional signatures that may be involved in ZIKV congenital pathogenesis.

Methods: Transcriptome data from placental tissues of pregnant women naturally infected with Zika virus during the third trimester were compared to those from women who tested negative for Zika infection. The findings were validated using both a cell culture model and an immunohistochemistry/morphological analysis of naturally infected placental tissues.

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The mosquito-borne viruses dengue (DENV) and Zika (ZIKV) viruses are two medically important pathogens in tropical and subtropical regions of the world. There is an urgent need of therapeutics against DENV and ZIKV, and medicinal plants are considered as a promising source of antiviral bioactive metabolites. In the present study, we evaluated the ability of , an endemic medicinal plant from Reunion Island, to prevent DENV and ZIKV infection in human cells.

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Article Synopsis
  • Researchers studied dengue fever in a big city in southern Brazil from 2012 to 2014, looking at patients who showed symptoms.
  • They found that out of 878 patients, 249 were confirmed to have dengue, showing it’s common in that area.
  • The study showed that higher dengue cases happened in poorer neighborhoods and that dengue cases increased a few months after it rained or when it was hot outside.
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The Zika virus (ZIKV) is an arthropod-borne virus that belongs to the Flaviviridae family. The ZIKV infection is usually asymptomatic or is associated with mild clinical manifestations; however, increased numbers of cases of microcephaly and birth defects have been recently reported. To date, neither a vaccine nor an antiviral treatment has become available to control ZIKV replication.

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Article Synopsis
  • Recent Zika virus (ZIKV) infections are linked to new clinical complications, suggesting adaptive mutations contributed to its emergence as a global health concern.
  • * The study focused on characterizing three ZIKV isolates from the 2015/2016 Brazilian epidemics through complete genome sequencing and infection experiments.
  • * Analysis revealed eight specific mutations in the viral genome that may affect the virus's ability to infect both mammalian and insect cells, showing differences in infectivity compared to established ZIKV strains.*
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In early 2017, an outbreak caused by an unknown and supposedly viral agent in the Marilena region of southern Brazil was investigated. Since the etiological agent causing the outbreak was not identified from human samples, mosquitoes from this region were collected. Three out of 121 mosquito pools collected from the region tested positive for alphavirus in molecular tests.

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Zika virus (ZIKV) and Dengue virus (DENV) are mosquito-borne viruses of the genus that could cause congenital microcephaly and hemorrhage, respectively, in humans, and thus present a risk to global public health. A preventive vaccine against ZIKV remains unavailable, and no specific antiviral drugs against ZIKV and DENV are licensed. Medicinal plants may be a source of natural antiviral drugs which mostly target viral entry.

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Background: The Zika virus (ZIKV) epidemics that affected South America in 2016 raised several research questions and prompted an increase in studies in the field. The transient and low viraemia observed in the course of ZIKV infection is a challenge for viral isolation from patient serum, which leads to many laboratories around the world sharing viral strains for their studies. C6/36 cells derived from Aedes albopictus larvae are commonly used for arbovirus isolation from clinical samples and for the preparation of viral stocks.

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