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Oropouche fever is an infectious disease caused by an arbovirus called Orthobunyavirus oropoucheensis (OROV). It was first isolated in Brazil in 1955 and has since been reported in various states in Brazil, including an increase of 448.86% in positive cases in 2024 compared to 2023. The primary vector for OROV is Culicoides paraenses, although other mosquito species can also transmit the virus. The clinical manifestations of Oropouche fever are similar to other arboviruses, but there is no specific treatment or vaccine available. The disease has emerged in Espírito Santo, a coastal state in Brazil, with several positive cases identified. Prevention measures include environmental management and individual protection. [Extracted from the article]

Dengue fever, caused by the dengue virus and transmitted by mosquitoes, has been a persistent health issue in Brazil. Recently, there has been an increase in cases of DENV-3 and DENV-4, in addition to the historically prevalent types 1 and 2. This may be due to changing climate patterns that favor the Aedes mosquito, the main vector for dengue transmission. The Brazilian Ministry of Health has reported a significant increase in dengue cases, with over 1.3 million possible cases in November 2023. The lack of diagnosed serotypes in most cases raises concerns about underreporting and the circulation of certain dengue serotypes. The recent outbreak of DENV-3 in São Paulo, after a 15-year absence, is particularly concerning and increases the risk of severe complications. It is important to enhance preventive strategies, especially for travelers to endemic regions, and collaborate on surveillance, research, and public health interventions to mitigate the impact of dengue fever. [Extracted from the article]

Background: High genetic diversity at both inter- and intra-host level are hallmarks of RNA viruses due to the error-prone nature of their genome replication. Several groups have evaluated the extent of viral variability using different RNA virus deep sequencing methods. Although much of this effort has been dedicated to pathogens that cause chronic infections in humans, few studies investigated arthropod-borne, acute viral infections. Methods and Principal Findings: We deep sequenced the complete genome of ten DENV2 isolates from representative classical and severe cases sampled in a large outbreak in Brazil using two different approaches. Analysis of the consensus genomes confirmed the larger extent of the 2010 epidemic in comparison to a previous epidemic caused by the same viruses in another city two years before (genetic distance = 0.002 and 0.0008 respectively). Analysis of viral populations within the host revealed a high level of conservation. After excluding homopolymer regions of 454/Roche generated sequences, we found 10 to 44 variable sites per genome population at a frequency of >1%, resulting in very low intra-host genetic diversity. While up to 60% of all variable sites at intra-host level were non-synonymous changes, only 10% of inter-host variability resulted from non-synonymous mutations, indicative of purifying selection at the population level. Conclusions and Significance: Despite the error-prone nature of RNA-dependent RNA-polymerase, dengue viruses maintain low levels of intra-host variability. [ABSTRACT FROM AUTHOR]

After detecting the death of Howlers monkeys (genus Alouatta) and isolation of yellow fever virus (YFV) in Buri county, São Paulo, Brazil, an entomological research study in the field was started. A YFV strain was isolated from newborn Swiss mice and cultured cells of Aedes albopictus - C6/36, from a pool of six Haemagogus (Conopostegus) leucocelaenus (Hg. leucocelaenus) mosquitoes (Dyar & Shannon) collected at the study site. Virus RNA fragment was amplified by RT-PCR and sequenced. The MCC Tree generated showed that the isolated strain is related to the South American I genotype, in a monophyletic clade containing isolates from recent 2008- 2010 epidemics and epizootics in Brazil. Statistical analysis commonly used were calculated to characterize the sample in relation to diversity and dominance and indicated a pattern of dominance of one or a few species. Hg. leucocelaenus was found infected in Rio Grande do Sul State as well. In São Paulo State, this is the first detection of YFV in Hg. leucocelaenus. [ABSTRACT FROM AUTHOR]

The author discusses safety aspects for the Rio 2016 Summer Olympic Games to be held in Rio de Janeiro, Brazil. Topics include information on the confirmed cases of measles globally, potential risk of measles transmission during the Olympics, and the preventive measures to consider to avoid the transmission of measles during the Olympics.

The article discusses how decreasing vaccine coverage rates lead to increased vulnerability to the importation of vaccine-preventable diseases in Brazil. It mentions that maintenance of high vaccine coverage is an important strategy for infectious diseases control in the context of increased global travel due to migration and tourism. It mentions analysis of data on recent infectious disease events in Venezuela.

Dengue is a vector borne disease caused by virus serotypes DENV-1, DENV-2, DENV-3, and DENV-4, representing a significant public health concern in the Region of the Americas (2,997,097 cases in 2023). This study explores the relationship between dengue incidence and climate changes in the city of São Paulo-Brazil. During the first semester of 2023, Brazil reported the highest number of dengue cases in Americas' Region. Our data reveals a correlation between the high temperature and rainfall season persistence and the extension of dengue incidence into the winter season. The findings highlight the importance of understanding the relationship between climate change and disease transmission patterns to develop effective strategies for prevention and control., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023. Published by Elsevier Ltd.)

Persistence may be defined as high sustained yield over multi-harvest. Genetic insights about persistence are essential to ensure the success of breeding programs and any biomass-based project. This paper focuses on assessing the biomass yield persistence for bioenergy purpose of 100 elephantgrass clones measured in six growth seasons in Brazil. To assess the clones' persistence, an index based on random regression models and genotype-ideotype distance was proposed. Results suggested the existence of wide genetic variability between elephantgrass clones, and that the yield trajectories along the harvests generate genetic insights into elephantgrass clones' persistence and G x E interaction. A gene pool that acts over the biomass yield (regardless of the harvest) was detected, as well as other gene pools, which show differences on genes expression (these genes are the major responsible for clones' persistence). The lower and higher clones' persistence was discussed based on genome dosage effect and natural biological nitrogen fixation ability applied to bioenergy industry. The huge potential of energy crops necessarily is associated with genetic insights into persistence, so just this way, breeding programs could breed a new cultivar that fulfills the bioenergy industries., Competing Interests: The authors have declared that no competing interests exist.

After detecting the death of Howlers monkeys (genus Alouatta) and isolation of yellow fever virus (YFV) in Buri county, São Paulo, Brazil, an entomological research study in the field was started. A YFV strain was isolated from newborn Swiss mice and cultured cells of Aedes albopictus - C6/36, from a pool of six Haemagogus (Conopostegus) leucocelaenus (Hg. leucocelaenus) mosquitoes (Dyar & Shannon) collected at the study site. Virus RNA fragment was amplified by RT-PCR and sequenced. The MCC Tree generated showed that the isolated strain is related to the South American I genotype, in a monophyletic clade containing isolates from recent 2008-2010 epidemics and epizootics in Brazil. Statistical analysis commonly used were calculated to characterize the sample in relation to diversity and dominance and indicated a pattern of dominance of one or a few species. Hg. leucocelaenus was found infected in Rio Grande do Sul State as well. In São Paulo State, this is the first detection of YFV in Hg. leucocelaenus.