Publications by authors named "Elaine C de Oliveira"

Influenza A and B viruses represent significant global health threats, contributing substantially to morbidity and mortality rates. However, a comprehensive understanding of the molecular epidemiology of these viruses in Brazil, a continental-size country and a crucial hub for the entry, circulation, and dissemination of influenza viruses within South America, still needs to be improved. This study addresses this gap by consolidating data and samples across all Brazilian macroregions, as part of the Center for Viral Surveillance and Serological Assessment project, together with an extensive number of other Brazilian sequences provided by a public database during the epidemic seasons spanning 2021-23.

View Article and Find Full Text PDF

Macrophages represent a fundamental component of the innate immune system that play a critical role in detecting and responding to pathogens as well as danger signals. Leishmania spp. infections lead to a notable alteration in macrophage metabolism, whereby infected cells display heightened energy metabolism that is linked to the integrity of host mitochondria.

View Article and Find Full Text PDF

Background: More than 95% of malaria transmission in Brazil occurs in the Legal Amazon Region, which in 2010 recorded around 333,429 cases reported in the Epidemiological Surveillance Information System-Malaria (Sivep_malaria), presenting an annual parasitic incidence (IPA) of 13.1 cases/1000 inhabitants.

Methods: This was a descriptive study that measured the community prevalence of Plasmodium infection and its relationship with land use in Três Fronteiras District, Colniza Municipality, Mato Grosso State.

View Article and Find Full Text PDF
Article Synopsis
  • The rising spread of arboviruses and increasing infection rates emphasize the urgent need for improved methods to rapidly and accurately detect these pathogens.
  • This study focuses on combining nanopore sequencing with reverse transcription polymerase chain reaction (RT-PCR) to create a multiplex RT-PCR protocol.
  • The new protocol allows the simultaneous detection of multiple viruses, including Chikungunya, dengue, Zika, yellow fever, and West Nile, enhancing our ability to differentiate between arbovirus strains effectively.
View Article and Find Full Text PDF

DENV-2 was the main responsible for a 70% increase in dengue incidence in Brazil during 2019. That year, our metagenomic study by Illumina NextSeq on serum samples from acute febrile patients (n = 92) with suspected arbovirus infection, sampled in 22 cities of the state of Mato Grosso (MT), in the middle west of Brazil, revealed eight complete genomes and two near-complete sequences of DENV-2 genotype III, one Human parvovirus B19 genotype I (5,391 nt) and one Coxsackievirus A6 lineage D (4,514 nt). These DENV-2 sequences share the aminoacidic identities of BR4 lineage on E protein domains I, II and III, and were included in a clade with sequences of the same lineage circulating in the southeast of Brazil in the same year.

View Article and Find Full Text PDF
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.
View Article and Find Full Text PDF
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.
View Article and Find Full Text PDF
Article Synopsis
  • - Brazil became a major COVID-19 epicenter in Latin America by May 2021, experiencing high transmission rates and deaths, but gaps remain in understanding how the virus spreads nationally.
  • - The study analyzes nearly complete SARS-CoV-2 genomes from Brazil and Paraguay, revealing that the initial wave was marked by multiple imported viral lineages mainly from Europe, leading to significant local transmission clusters.
  • - As the pandemic progressed without effective restrictions, Brazil saw the emergence and spread of concerning variants like Gamma and Zeta, highlighting the need for extensive genomic surveillance in South America for better pandemic management and public health strategies.
View Article and Find Full Text PDF

Background: Leishmaniasis is a neglected arthropod-borne disease that affects millions of people worldwide. Successful infections require the mitigation of immune cell functions leading to parasite survival and proliferation. A large body of evidence highlights the involvement of neutrophils (PMNs) and dendritic cells (DCs) in the establishment of immunological responses against these parasites.

View Article and Find Full Text PDF

Brazil experienced a large dengue virus (DENV) epidemic in 2019, highlighting a continuous struggle with effective control and public health preparedness. Using Oxford Nanopore sequencing, we led field and classroom initiatives for the monitoring of DENV in Brazil, generating 227 novel genome sequences of DENV1-2 from 85 municipalities (2015-2019). This equated to an over 50% increase in the number of DENV genomes from Brazil available in public databases.

View Article and Find Full Text PDF

Since introduction into Brazil in 2014, chikungunya virus (CHIKV) has presented sustained transmission, although much is unknown about its circulation in the midwestern states. Here, we analyze 24 novel partial and near complete CHIKV genomes from Cuiaba, an urban metropolis located in the Brazilian midwestern state of Mato Grosso (MT). Nanopore technology was used for sequencing CHIKV complete genomes.

View Article and Find Full Text PDF

The Northeast region of Brazil registered the second-highest incidence proportion of Chikungunya fever in 2019. In that year, an outbreak consisting of patients presenting with febrile disease associated with joint pain was reported by the public primary health care service in the city of Natal, in the state of Rio Grande do Norte, in March 2019. At first, the aetiological agent of the disease was undetermined.

View Article and Find Full Text PDF

Introduction: Brazil's western Amazon basin has the highest prevalence of hepatitis B virus (HBV) infection in the country. Coinfection with hepatitis D virus (HDV) is also endemic. To estimate the prevalence of HBV and HDV markers in a population inhabiting the northwest portion of Mato Grosso state in the western Amazon.

View Article and Find Full Text PDF

Photodynamic therapy is a minimally invasive health technology used to treat cancer and other non-malignant diseases, as well as inactivation of viruses, bacteria and fungi. In this work, we sought to combine the phototherapy technique using low intensity LED (660 nm) to induce ablation in melanoma tumor in mice treated with nanoparticles. In vitro and in vivo studies were conducted, and our results demonstrated that multi-walled carbon nanotubes (MWCNTs) do not destroy tumor cells in vivo, but stimulate the inflammatory process and angiogenesis.

View Article and Find Full Text PDF

Background: In view of the wide variety of the flora of the Amazon region, many plants have been studied in the search for new antimalarial agents. Copaifera reticulata is a tree distributed throughout the Amazon region which contains an oleoresin rich in sesquiterpenes and diterpenes with β-caryophyllene as the major compound. The oleoresin has demonstrated antiparasitic activity against Leishmania amazonensis.

View Article and Find Full Text PDF

Objective: to report the experience of investigating the outbreak of acute diarrhoea (AD) at the XII Indigenous Games in Cuiabá, Mato Grosso, Brazil, 2013.

Methods: data were collected from the Advanced Medical Post's service records of the AD cases, which were defined as 'individual Games participant referring episode of diarrhoea and/or vomiting'; AD attack rates, relative frequencies and measures of the central tendency of sociodemographic and clinical variables, sanitary inspections and results of bromatological samples were calculated.

Results: 384 (37%) cases met the definition of AD; the epidemic peaks of the outbreak occurred on the 4th and 7th day of the event and the disease attack rate was 33.

View Article and Find Full Text PDF

Background: In Brazil, 99% of the cases of malaria are concentrated in the Amazon region, with high level of transmission. The objectives of the study were to use geographic information systems (GIS) analysis and logistic regression as a tool to identify and analyse the relative likelihood and its socio-environmental determinants of malaria infection in the Vale do Amanhecer rural settlement, Brazil.

Methods: A GIS database of georeferenced malaria cases, recorded in 2005, and multiple explanatory data layers was built, based on a multispectral Landsat 5 TM image, digital map of the settlement blocks and a SRTM digital elevation model.

View Article and Find Full Text PDF

Background: In Brazil, 99% of malaria cases are concentrated in the Amazon, and malaria's spatial distribution is commonly associated with socio-environmental conditions on a fine landscape scale. In this study, the spatial patterns of malaria and its determinants in a rural settlement of the Brazilian agricultural reform programme called "Vale do Amanhecer" in the northern Mato Grosso state were analysed.

Methods: In a fine-scaled, exploratory ecological study, geocoded notification forms corresponding to malaria cases from 2005 were compared with spectral indices, such as the Normalized Difference Vegetation Index (NDVI) and the third component of the Tasseled Cap Transformation (TC_3) and thematic layers, derived from the visual interpretation of multispectral TM-Landsat 5 imagery and the application of GIS distance operators.

View Article and Find Full Text PDF